INFLUENCE OF BODY WEIGHT ON EVALUATING LEG POWER WITH

MARGARIA-KALAMEN STAIR-RUN TEST IN YOUNG ADULTS

BY

LEUNG CHI HUNG 05006341

AN HONOUR PROJECT SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF

BACHELOR OF ARTS

IN

PHYSICAL EDUCATIOIN AND RECREATION MANAGEMENT (HONOURS)

HONG KONG BAPTIST UNIVERSITY

APRIL 2008

HONG KONG BAPTIST UNIVERSITY

25th April, 2008

We hereby recommend that the Honours Project by Mr. Leung

Chi Hung entitled “The influence of body weight on evaluating

leg power with the Margaria-Kalamen Stair-Run Test in young

adults” be accepted in partial fulfillment of the

requirements for the Bachelor of Arts Honours Degree in

Physical Education And Recreation Management.

__________________________ _________________________

Dr. Tom Tong Dr. Lobo Louie

Chief Adviser Second Reader

ACKNOWLEDGEMENTS

I would like to express my deepest gratitude to my chief

adviser, Dr. Tom Tong, for his patience, kindness,

encouragement and professional guidance throughout the whole

project. I have furthermore to thank Dr. Lobo Louie to be

my second reader.

I want to give my thanks to Ms. Ellen Lu, the executive

assistant and Mr. Binh Quach, the lab technician of Dr.

Stephen Hui Centre for Physical Recreation and Wellness, for

guiding me to use the apparatus in the laboratory. Finally,

my gratitude also goes to all the students for their sincere

participation.

Leung Chi Hung Department of Physical Education

Hong Kong Baptist University

Date: 25th April, 2008

ABSTRACT

Body weight was considered as a critical variable in

Margaria-Kalamen Stair-run Test (MST) assessing the maximal

anaerobic power (MAP) of the lower body. It was also thought

to inherently mask the true MAP and impair the validity of

MST. The first part of study determined the validity of MST

of assessing the MAP among 17 young active adults with

comparison of the total leg power in isokinetic knee extension

test with angular velocities of 120o/s and 180o/s. A

significantly positive correlation between MAP in MST and

total leg power in isokinetic knee extension test was found

(r = 0.869, p < 0.05). This justifies that MST is valid to

assess MAP of the lower body. Body weight does not impair the

validity of MST. The second part of study investigated the

effect of external weight (EW) of 28% body weight (BW) on MAP

in MST within the groups of young males (n = 7) and females

(n = 10) adults. Significant increases (male: t = 6.82, female:

t = 4.55, p < 0.05, one-tailed) in MAP for MST with EW of 28%

BW. This shows that EW of 28% achieves a greater MAP in MST.

TABLE OF CONTENTS

CHAPTER Page

1. INTRODUCTION................................... 1

Part One: Validity of Margaria-Kalamen Step-run Test (MST assessing Maximal Anaerobic Power

Introduction...........................

Statement of the Problem.................

Purpose of the study.....................

2

3

4

Part Two: Effects of External Loading on Maximal Anaerobic Power in MST

Introduction...........................

Statement of the Problem.................

Purpose of the study.....................

4

6

6

Significant of the study.................... 6

2. REVIEW OF LITERATURE............................ 8

Part One:

Isometric, Isokinetic and Isotonic Dynamometry for measuring the Lower Body Power and Strength ......................

Comparison of Isometric, Isokinetic and

Isokinetic Dynamometry for assessing the Lower Body Power........................

Movement-Related Factors in Isokinetic

Testing................................

8 10 12

Part Two:

Maximal Anaerobic Power and the Relevant Factors ................................

Factors affecting the performance in

stair-run test..........................

Mode of External Loading in MST...........

18 20 25

Summary.................................... 26

Definition of Terms

1. Concentric muscle action..........

2. Torque...........................

3. Peak power........................

28

28

28

Research Hypotheses

Part One...............................

Part Two...............................

28

29

3. METHOD......................................... 30

Subjects.................................. 30

Test One: Isokinetic reciprocal knee extension and flexion test

Procedures............................

Delimitations.........................

Limitations...........................

Instruments...........................

Measurement...........................

Data analysis.........................

30

33

33

34

34

34

Test Two: Margaria-Kalament Stair-run Test

Procedures............................

Delimitations.........................

Limitations...........................

Instruments...........................

Measurement...........................

Data analysis.........................

35

37

37

38

38

39

4. ANALYSIS OF DATA................................ 40

Part One:

Results...................................

Discussions...............................

40

43

Part Two:

Results...................................

Discussions...............................

45

49

5. SUMMARY AND CONCLUSIONS......................... 54

Summary of Results......................... 54

Conclusions............................... 55

Recommendations of Further Study............ 55

REFERENCES........................................ 57

APPENDIX

A. Consent Form to Subjects........................ 65

B. Setting of Margaria-Kalament Stair-Run Tests and the mode of external load carriage.............

67

C. Data Collection Forms........................... 70

LIST OF TABLES

TABLE Page

1. Physical Characteristics and the power of the knee extensors and flexors in isokinetic knee extension and MST of the participants (n=17).............

41

2. Pearson’s correlation test of the MAP of the lower body resulting from MST with isokinetic knee extension test (N=17)...........................

42

3. Physical Characteristics of the male (n=7) and female (n= 10) participants in MST...............

46

4. Descriptive data of Males (n = 7) and Female (n = 10) in between the Margaria-Kalamen Stair-run tests (N=7)....................................

47

5. Paired t-tests of Maximal Anaerobic Power (MAP), Traveled Time, and Total Weight of Males (n = 7) and Female (n = 10) in between the Margaria-Kalamen Stair-run tests................................

48

6. One-Sample Test between the weight of the external load used in practical (EW/BW %) and the expected percentage of the external load of 28% of body weight in MST (n = 7 in males, n = 10 in females)

49

LIST OF FIGURES

FIGURE

1. Scatter-plots showing the Correlation between MST and the isokinetic knee extension test of assessing the MAP of the lower body for all subjects (n=17).

42

Chapter 1

INTRODUCTION

Background

Anaerobic power is a major concern on the performance in

explosive types of human movement like sprinting, jumping,

kicking and throwing (Markovic & Jaric, 2005). Assessment on

muscle power is extensively used in physical education and

sports professional field for selecting sports team members

as well as supervising their training progressions. The

present study mainly focuses on Margaria-Kalamen Stair-Run

Test (MST), one of the universally-accepted and effective

field tests assessing the maximal anaerobic power (MAP) of the

lower limb (Mayhew & Salm, 1990). The principle of MST is based

on the traveled time of running up from the third to ninth stairs

with two steps. MAP is calculated by the product of body weight,

acceleration of gravity, and vertical distance between the

third and ninth stairs divided by the traveled time and the

standard formula is shown below:

(s) timeledbest trave The819)(m distance vertical)kg(t Body Weigh

)W(MAP1−××

=ms .

This study mainly focuses relationship of the body weight and

MAP in MST.

Part One:

Validity of Margaria-Kalamen Stair-run Test assessing the

Maximal Anaerobic Power.

Introduction

The measurement of maximal anaerobic power under MST is

inevitably proportional to body mass. Kitagawa, Suzuki and

Miyashita (1980) showed that people with a larger body weight

took advantage in a higher value of anaerobic power output

although the vertical velocity slowed down. Therefore, body

mass is believed to impair the validity of the test in assessing

the anaerobic power of the lower-limb.

Isokinetic knee extension test is also a useful and reliable

tool assessing the peak power of the knee extensors and flexors

in laboratory (Timm & Fyke, 1993). It is used to evaluating

the isolated active muscle group without the consideration of

body weight while the MST is nonspecific in terms of the

involved muscles. Previous studies found that isokinetic

torques about the knee joint were moderately and highly

correlated to the performance of vertical jump (e.g. Destasio,

Kaminski, & Perrin, 1997; Tsiokanos, Kellis, Jamurtas, &

Kellis, 2002). Iossifidou, Balzopoulos & Giakas (2005) also

recognized knee extension power output as the major

contributors in vertical jump, thus the MAP of the isolated

knee extensors and flexors could be measured specifically by

isokinetic concentric knee extension test. Although MST was

claimed to be a suitable predictor of the performance of

vertical jump (Davis, Briscoe, Markowski, Saville, & Taylor,

2003), no researches investigate the correlation between MST

and isokinetic knee extension test on maximal anaerobic power.

Meanwhile, the validity of MST on testing the MAP has not been

reported yet.

Statement of the problem

The research problems are (1) whether the body mass would

impair the validity of Margaria-Kalamen Stair-run Test (MST)

assessing the maximal anaerobic power; (2) the contribution

of the knee extensors and flexors to the maximal anaerobic power

in MST is unknown.

Purpose of the study

The study aims at (1) comparing the maximal anaerobic power

(MAP) upon Margaria-Kalamen Stair-run Test (MST) and

Isokinetic knee extension test through correlation in order

to investigate whether body mass would weaken the validity of

MST on MAP; (2) specifying the correlation between MAP of the

knee extensors and flexors through isokinetic knee extension

test and the performance of the MST.

Part Two:

Effects of External Loading on Maximal Anaerobic Power in

Margaria-Kalamen Step-run Test.

Introduction

Despite the standard formula of MAP in MST, power is also

dependent on force and vertical velocity [Power (W) = Force

(N) x velocity]. MST requires a high level of skill which

greatly enhances the vertical velocity and results in a greater

power output. Individuals may show difference on habituating

the technique in MST according to their ability (Mayhew,

Schwegler, Piper, 1986). Therefore, external loading is

suggested to eliminate the variance on vertical velocity.

Non-athletes with greater weight also resulted in greater

amount of maximal anaerobic power than the professional

athletes (e.g. in sprinting and jumping) with less weight under

the application of the formula in MST (Hong & Liao, 2004;

Nedeljkovic, Mirkov, Pazin, & Jaric, 2007). Therefore, Caiozzo

and Kyle (1980) recognized the problem as body weight might

not be the optimal load for generating the maximal anaerobic

power. Meanwhile, Hong (1999) also discovered that adding a

certain amount of external load with related to body weight

would result in a greater power output than that without

external load. The external weight (EW) was 28% of body weight

(BW) was speculated to the greatest MAP and the range of EW

would be 20% to 35% BW. However, Zhao and Hong (2001) indicated

that the MAP and related EW of male were greater than those

of female. EW for male was 28%BW while that for female was nearly

19%BW but the research just restricted on the college

sprinters.

Statement of the problem

The research problem is whether the 28% of body weight (BW)

would result in a greater power output than the original in

both physically active male and female.

Purpose of the study

The study aims at (1) comparing the maximal anaerobic power

(MAP) with and without the EW of 28% of BW; (2) finding whether

proposed EW of 28% BW would be proper to both male and female

resulting in a MAP.

Significance of the Study

In short, this study is purposed of distinguishing whether

Margaria-Kalamen Stair-run Test (MST) alone or with the

utilization of EW of 28% is valid and reliable to evaluate the

muscle maximal power output in physical assessment and

training with confident evidences. Physical educators and

coaches are then able to choose properly and precede accurately

MST in field for further studies and conditioning.

Chapter 2

REVIEW OF LITERATURE

Power is inevitably being studied among human beings due

to its importance for different purposes throughout our daily

lives such as sport activities and training, as well as

evaluation and rehabilitation of patients in physical therapy.

This chapter concerns on power of lower extremity and involves

two sessions: 1) Review of different types of dynamometry for

measuring leg power and some major factors affecting the result

in isokinetic assessment on maximal anaerobic power in lower

body; 2) Review of Margaria-Kalamen Stair-run Test with

external loading;

Part One:

Validity of Margaria-Kalamen Stair-run Test Assessing the

Maximal Anaerobic Power.

Isometric, Isokinetic and Isotonic Dynamometry for measuring

the Lower Body Power and Strength

Generally, isometric, isokinetic and isotonic dynamometry

were used in assess the muscular function of our lower body.

Before recognizing the features and drawbacks, we should

understand the definition of isometric, isokinetic and

isotonic and distinguish these key terms.

Isometric

“Isometrics” was used to describing the exercise in which

muscle generated force without any changes in muscle length

and skeletal movement. The resistance was fixed and the speed

was also fixed at 0o/s (Davies, Heiderscheit & Brinks, 2000).

Cable tensiometer was utilized to measure the isometric force

of the leg during a static knee extension.

Isokinetic

“Isokinetic” was used to describing the exercise in which

muscle moved at a constant speed with the use of accommodating

resistance (Davies, Heiderscheit & Brinks, 2000). Isokinetic

dynamometer was utilized to provide detailed information about

the differences in force-generation over the full range of

movement.

Isotonic

“Isotonic” was also called “isoinertial” because a constant

load was used with a variable speed over a dynamic exercise

which involved a range of movement of body parts (Davies,

Heiderscheit & Brinks, 2000; Powers & Howley, 2004, p.152,

418-419). Margaria-Kalamen Stair-run tests (MST), Wingate

Cycling test were the examples of isotonic dynamometry of

assessing the leg power. MST, which was the major concern in

our study, used body weight as the constant load and measured

the traveled time and speed for assessing the lower body power.

Comparison of Isometric, Isokinetic and Isokinetic

Dynamometry for assessing the Lower Body Power

Cronin and Sleivert (2005) mentioned that dynamic

(isoinertial) multiarticular motion was more significantly

practical for investigating the power-load spectrum, whereas

isometric tests bore too little resemblance to the dynamic

nature of most sporting activities (Ashley & Weiss, 1994) as

human beings seldom needed to produce maximum force which would

last too long to have any practical value in reality (Vittasalo

& Komi, 1978) as well as no power output would be obtained due

to zero speed for muscle contractions.

On the other hand, isokinetic test bore too little

resemblance to functional performance as it assess

single-joint and isolated muscle without acceleration and

stretch-shortening cycle due to the constant movement

speed(Augustsson, Esko, Thomeé & Svantesson, 1998). Weiss

(2000) also questioned about the application of the test and

stated “it was unclear if velocity-match isokinetic test will

reflect concomitant performance changes in other activtities”

(p. 201). Currently, some researches reported a low, fair to

moderate correlation between isokinetic knee extension torque

and vertical jump performance (Blackburn & Morrissey, 1998;

Malliou, Ispirlidis, Beneka, Taxildaris & Godolias, 2003).

However, it was no doubt to the high accuracy of isokinetic

test because of its great specificity of assessed muscle fiber

and therefore, it was widely used for prediction of sports

performance (Alexander, 1989; Saliba & Hrisomallis, 2001;

Wilson & Murphy, 1995). Furthermore, power output under

isokinetic dynamometry was not confronted with the effect of

body mass in the isotonic assessment like Margaria-Kalamen

Stair-run test. Aiming to improve the validity, Iossifidou,

Baltzopoulos and Giakas (2005) suggested recognizing the

details of different muscle and joint function characteristics

for different activities before using isokinetic test for

predicting the functional performance.

Movement-Related Factors in Isokinetic Testing

A proper designed of protocol in isokinetic assessment was

necessary for functional application and predication in

physical therapy and sports science. Osternig (2000) mentioned

some movement-related factors in isokinetic test.

The amount of force generated in a musculotendinous unit

was greatly influenced by interactions between the

characteristics of the muscle action (concentric or

eccentric), the position at which force was measured,

and the speed of movement. Power produced or absorbed

by the musculotendinous unit was similarly influenced

by these variables. (p.82)

Muscle Action

Isokinetic testing could be done by concentric and

eccentric muscle contraction. As our study focuses on

concentric knee extension and flexion only, we would just

mention the concentric muscle contraction in which was found

the force-velocity relationship. Concentric force output

decreased with increasing velocity (Hill, 1938). On the other

hand, changing velocity from low to high, we would obtain that

power was low initially, then rose to the peak level

intermediately and decreased after that (Weiss, 2000).

Joint Angle

Torques would be varied with different joint angle (Mira,

Carlisle & Greer, 1980). There were no reports about

standardization of range of joint angle being used in

isokinetic test (Keating & Matyas, 1996). However, it could

be determined based on the research area, muscle group being

assessed, and type of population etc. Scott Davis, Briscoe,

Markowski, Saville and Taylor (2003) used the joint angle

between 85o to 20o (0o = full extension) to assess the isokinetic

quadriceps power and peak force for predicting the vertical

jump performance among the ordinary people, whereas Tsaklis

(2002) used 120o to 00 to assess the knee extensors and flexors

anaerobic capacity among the athletes in track and field.

Actually, peak torque was always measured as a golden standard

and reference point in all isokinetic studies (Alangari and

Al-Hazzaa, 2003). The range of joint angle should be within

the angle for peak torque (APT). In fact, Kovaleski and Heitman

mentioned the APT would be about 72o to 55o of knee extension

and 20o to 45o of flexion with the velocity between 180o/s and

240o/s. Slocker de Arce, Carrascosa Sánchez, and Fernandez

Camacho (2001) reported that the angle of peak torque (APT)

coincided with greater arc of motion of both knee flexion and

extension as the velocity increased. This implied that the

range of joint angle had to interact with angular velocity for

assessing isokinetic power and force among a specific

population.

Angular Velocity

Isokinetic dynamometry aimed at providing constant

velocity for the body movement. The magnitude of the torque

and power measured were greatly attributed to the

determination of angular velocity. Isokinetic torque

decreases with increasing angular velocity under the

torque-velocity relationship in concentric muscle contration.

Kraemer, Mazzetti, Raamess and Fleck (2000) reported “an

intermediate speed of about 179o/s was the most advantageous

for gains across velocities of movement in average power (How

about peak power?)”(p.32). However, this study only mentioned

the average power. For elite athletes, the instantaneous power

was rising and had not reached the maximum even for the angular

velocity of 300o/s (Taylor, Cotter, Stanley and Marshall,

1991).

Although there were no studies on the correlation of the

maximal anaerobic power between isokinetic knee extension /

flexion and Margaria-Kalamen stair-run test, many researches

used isokinetic assessment to predict the performance in

vertical jump test (Iossifidou, Baltzopoulos & Giakas, 2005;

Liebermann & Katz, 2003; Malliou, Ispirlidis, Beneka,

Taxildaris & Godolias, 2003; Scott Davis, Briscoe, Markowski,

Saville & Taylor, 2003). The above research findings showed

the test at slow velocities such as 60o/s could not be used

for predict performance in vertical jump, whereas higher

angular velocity would be recommended. We should be treat it

carefully since isokinetic test with a high velocity, which

implied that a light accommodating load was applied on the

subject, would not simulate the real situation of vertical jump

test and Margaria-Kalamen Stair-run test in which involved a

certain amount of constant load (body mass). In general,

angular velocity between 120o/s to 400o/s with 3 to 6

repetitions of contractions was suggested to evaluate the

power in isokinetic knee extension /flexion (Kovaleski &

Heitman, 2002).

Repetitions

Brown and Whitehurst (2000) defined one repetition as

“completing a range of motion movement for both the agonist

and antagonist muscle groups” (p.102). Similar to other

factors and components of testing protocol, the number of

repetitions should be based on the purpose of study and it was

also concomitant with angular velocity and joint angle.

Repetitions used in isokinetic tests were not standardized

but had some principles. For evaluating power and strength,

fewer repetitions should be applied. Brow and Whitehurst (2000)

recommended performing not more than 5 repetitions, whereas

Davies, Heiderscheit and Brinks (2000) told to use not more

than 10 repetitions. However, Davis et al. (2003) apply 15

continuous repetitions for power test of the quadriceps. The

difference of the repetitions would be related to the different

angular velocity and joint angle used in tests.

Furthermore, many studies confirmed that a number of

consecutive isokinetic trials would be better than a single

trial (Johnson & Siegel, 1978; Murray, Gardner & Mollinger,

1980; Stratford, 1991). Burdett and Swearingen (1989) reported

that peak torques for knee extension and flexion test were found

more likely in second or third repetition than in first one.

Part Two:

Effects of External Loading of 28% Body Weight on Maximal

Anaerobic Power in Margaria-Kalamen Stair-run Test.

Maximal Anaerobic Power and the Relevant Factors

Mayhew, Schwegler and Piper (1986) defined maximal

anaerobic power (MAP), mechanically, as “the exertion of

greatest force through short distances in minimal time through

a rapid, vigorous movement from a stationary position or after

a short running approach” (p.209). Generally, MAP was measured

over a short period of time within 1 to 5 seconds. While force

and velocity were the important components of maximal

anaerobic power, Cronin and Sleivert (2005) believed that MAP

would be produced under the optimum force generated and optimum

shortening velocity of muscle fibers. Reader should be

cautious to the word “optimum” describing the force and

shortening velocity since these two terms were

inversely-related. Hill (1938) suggested that maximum power

output would be generated at either approximately 30% of

maximum shortening velocity or approximately 30% of maximum

isometric force based on the force-velocity relationship of

muscle.

Mayhew, Schwegler and Piper (1986) also defined maximal

anaerobic power (MAP), physiologically, as “the capacity of

the phosphocreatine energy system to rapidly regenerate

adenosine triphosphate (ATP)” (p.209). Relating to the muscle

force production, Bouissou, Estrade, Goubel and Guezennec

(1989) mentioned the central factors such as motor centers and

motor neuron excitability and peripheral factors such as

muscle acidity and phosphocreatine depletion. Further, fiber

length referring to the number of sarcomeres arranged in series

(Cronin & Sleivert, 2005), the activity of Myosin (Barany,

1967)stimulated by the activity of Mg2+, and Ca2+ released from

the sarcotubules (Viitasalo & Komi, 1978) were the detriments

of the shortening velocity in muscle fibers.

Factors affecting the performance in stair-run test

There were two types of factors affecting the maximal

anaerobic power in Margaria-Kalamen Stair-run test 1)

Methodological factors and 2) Subject-related factors.

Methodological factors included external loading, stride

height, and approaching run distance. Biological factors were

related to body composition and motor skill and coordination.

External Loading

Referring to the force-velocity relationship during

concentric muscle contraction, force output increased while

the shortening velocity decreased with an increasing load

(Hill, 1938). Therefore, an optimal velocity would contribute

to maximal power under the parabolic relationship between

power and velocity. Sargeant (1998) claimed to identify the

optimal velocity for whole-body exercise. Instead, Caiozzo and

Kyle (1985) suggested that an optimal loading condition could

be used to determining the maximal power output. Martin and

Nelson (1986) discovered that stride length was forced to

decrease with increasing carried load in walking for men and

women. It might exactly happen in Margaria-Kalamen Stair-run

Test (MST) with external loading. As the stride length

decreases, stride frequency was necessary to increase with

external effort. Therefore, a greater peak power would be

generated.

However, studies of whether power would be increased by

loading remained conflict. Davies and Young (1984) found a

linear decrease in power proportional to the percentage of

weights added. Caiozzo and Kyle (1980) reported that addition

of weights within 10 to 30 kg increase the power output by 6

to 16 % in MST, whereas the external weight of 29.2 kg would

be optimal. Recent research also indicated the optimal

external loading for young adult men and women would be about

28 % and 19% of body weight respectively (Hong, 1999; Hong &

Liao, 2004). These studies were not consistent to express the

optimal external load in either absolute value of weight or

percentage of body weight.

Stride Height

Margaria, Aghemo and Rovelli (1966) stated that the step

height would influence the maximal anaerobic power in MST.

Although there were only a few research studying the effect

of step height in MST due to the difficulties of choosing the

desired stairs for test in reality, Hung et al. (1994)

discovered the optimal vertical height for each stride would

be within 45 to 55% of the body height, whereas 20% of body

height was improper for stride height in MST, where explosive

power was hard to generate. Furthermore, stride height of 40%

of their body height would be suitable for athletes who

participated in sprinting and jumping while stride height of

30% of body height would be appropriate to general people. Other

factors on determination of stride height would be flexibility

and stride length of subjects. However, varying for stride

height was more inconvenient and impractical than applying

external load in MST.

Approaching Run Distance

Husky, Mayhew and Ball (1986) stated that approached run

distance (prior stepping stairs) of 6m and 10m would achieve

peak power more likely than that of 2m. However, Mayhew,

Schwegler and Piper (1986) mentioned that “the effect of the

horizontal velocity on power production was minor when

compared to the effect of body weight” (p.212).

Body Composition

Kitagawa, Suzuki and Miyashita (1980) recognized that the

maximal anaerobic powers with both absolute and relative

values of obese subjects were significantly superior to the

lean and ordinary subjects in MST although the obese had the

lowest vertical velocity. The obese subjects overcame their

disadvantage of lower velocity in MST, which was more likely

to be mass-power test rather than speed-power test because of

the extensive involvement of body weight in the calculation

of anaerobic power (Kitagawa et al., 1980; Mayhew, Schwegler,

& Piper, 1986). Furthermore, Obese subjects, who had a higher

percentage of body fat, attributed to a greater body weight

resulting in a significantly higher power output in MST. On

the other hand, Kitagawa et al. utilized external loads to

investigate the effect of “artificial obesity” who generated

the power output as high as the “obese”. Therefore, the excess

amount of body fat also treated as the external load regarding

to the lean and ordinary people.

Skill and Coordination

Margaria-Kalamen Stair-run test (MST) required high level

of skills although there were no study on the correlation

between motor ability and power output in MST (Mayhew,

Schwegler, & Piper, 1986). Huskey, Mayhew, Ball and Arnold

(1989) also strongly believed that the motor ability might be

one of the major factors limiting the explosive power output

in stair-run for female. However, the learning effect within

the test could be minimized by providing the subjects several

trials before testing and a greater maximal anaerobic power

would be obtained after that (Davies & Young, 1984; Schwegler,

Mayhew, & Piper, 1985).

Mode of External Loading in MST

Mode of external loading might change the running and

stepping pattern as well as the centre of gravity. Power output

might therefore be affected. A proper mode of external loading

should be used to not only improve the test validity and

reliability, but also prevented subjects from injury during

the test process.

Firstly, Caiozzo and Kyle (1980, 1985) used a specially

constructed vest in which weights were equally distributed

between the chest and back while Davies and Young (1984) also

stated that loads were inserted into small pockets and evenly

distributed over the body. However, the latter authors did not

mention the location of the pockets put around the subjects’

bodies. Meanwhile, Kitagawa et al. used a loading belt attached

around the waist of the subject but the design of the belt with

load was not mentioned. These showed the mode of carrying

external load in the previous studies were inconsistent.

Legg and Mahanty (1985) compared the physiological and

subjective cost of six different modes of carrying a load

equivalent to 35% body weight. D ouble pack, where the load was

divided equally into two packs, one in front of the body and

the other on the back, was less strain associated and more

comfortable than others. It was recommended since it involved

a large group of muscles to carry the load with a large area

of support while the centre of gravity was kept near to the

original (Legg, 1985).

Secondly, material for external loads was another concern

which was less important than the carrying approach. Davies

and Young (1984) used steel while Zhao and Hong (2001) used

“sand”, whereas some studies did not report the material of

the external load (Kyle & Caiozzo, 1985; Kitagawa et al., 1980).

Summary

The first session described and compared isometric,

isotonic and isokinetic dynamometry. Muscle action, joint

angle, angular velocity and repetitions were the most

essential movement-related factors and components in

isokinetic tests. The purpose of the isokinetic study would

be consistent with a specific protocol with these components.

It was necessary to determine these aspects properly prior the

test.

The second session of this chapter initially introduced

the mechanical and physiological meaning of maximal anaerobic

power explained by the components, velocity and force which

were related with the several physiological factors. Both

methodological factors and subject-related factors affecting

the performance in Margaria-Kalamen Stair-run test (MST) were

including the external loading, stair height, approaching run

distance, body composition as well as skill and coordination

were reviewed. Double pack was recommended loading in MST with

comparison of several studies in the mode of external loading.

Definition of Terms

Some of the terms had been defined in the previous part

of literature review. The key terms and parameters below were

related to isokinetic tests.

1. Concentric muscle action:

The muscle tension developed when the origin and insertion

of the muscle approach each other, also called positive

work (Davies, Heidercheit & Brinks, 2000).

2. Torque:

A force that produces or tends to produce a rotation about

a point or axis, measured in units of newton-meters (Nm)

(Davies, Heidercheit & Brinks, 2000).

3. Peak power

The maximum product of the (angular) velocity times its

peak torque (Davies, Heidercheit & Brinks, 2000).

Research Hypotheses

Part One:

Validity of Margaria-Kalamen Stair-run Test assessing the

maximal anaerobic power.

1. The correlation between original Margaria-Kalamen

stair-run test (MST) and isokinetic knee extension and

flexion test on MAP of the lower extremity would be

significant.

Part Two:

Effects of External loading of 28% BW on maximal anaerobic power

in Margaria-Kalamen Stair-run Test.

1. There would be a significant increase in maximal anaerobic

power (MAP) with the external loading of 28% body weight

(BW) within male and female subjects respectively.

Chapter 3

METHODOLOGY

Subjects

Twenty physically active subjects (ten males, ten females)

volunteered to participate in this study. All of them were

students at the Hong Kong Baptist Universities, aged within

19 to 25 years old. Subjects were reported healthy without any

significant history of lower extremity pathology. Informed

consent was obtained in written from each subject by

understanding the purpose of study, procedures and potential

risks before the test started (See Appendix A). Subjects were

undergone by two studies of their maximal anaerobic power in

two separated days within one week: 1) Isokinetic knee flexion

and extension test in laboratory and 2) Margaria-Kalamen

stair-run test (MST) in field.

Isokinetic reciprocal knee extension and flexion test

Procedures

Isokinetic reciprocal knee extension and flexion test was

designed for measuring the total power of the knee extensors

and flexors of both right and left legs. The test was conducted

in laboratory, the Dr. Stephen Hui Research Centre for Physical

Education and Wellness at the Hong Kong Baptist University,

with room temperature of 22oC and relative humidity of 70%.

Isokinetic Dynamometer (HUMAC NORM, CSMI, Boston, USA) with

the Norm software (HUMAC 2004) were used to assessing the total

leg power of the subjects which correlated to the MAP in MST.

Body weight in kilogram and height in meter were measured

before the test began. A five-minute of cycling with the load

of 100W and rate per minute (RPM) of 60 was preceded the actual

test for warming up. At the same time, the dynamometer was

calibrated according to the procedures of the computer

software program prescribed by the manufacturer and a standard

dynamometer chair for the subject was set. Subject was then

placed on the dynamometer chair with upright seated position

with back slightly reclined. Pelvic, distal femur and lower

leg at the distal tibia above the ankle joint superior to the

medial malleolus were strapped to minimize extraneous body

movement. Subject was instructed to grip their hands around

the chest during the test. Range of motion was measured for

setting the locks. Gravitation correction of the torque

measurements was done with the tested knee in a relaxed from

terminal extension by the dynamometer software. Subject was

positioned in comfort on the machine.

Subject was required to have 5 repetitions of reciprocal

knee extension and flexion of the tested limb in maximal

intensity with the angular velocity of 120o/s or 180o/s on the

dynamometer in order to familiar to the test and machine. Two

minutes were given for rest before the actual test. After that,

the actual test was initiated with 5 repetitions in maximal

intensity with 120o/s or 180 o/s. Verbal encouragements such

as “try as hard as you can” were used. Similarly, 2 minutes

of rest was provided after that and the test would be carried

on by changing another angular velocity of either 120o/s or

180o/s which was not tested, starting from warm-up on the

machine. Legs were being assessed on both sides. The order of

the angular velocity and sides of leg tested were randomized.

Delimitations

1. 20 young adults who were aged between 19 and 25 and

physically active at the universities in Hong Kong were

invited to be the subjects.

2. Isokinetic reciprocal knee extension and flexion test was

undergone in laboratory at the Dr. Stephen Hui Research

Centre for Physical Education and Wellness at the Hong Kong

Baptist University.

3. The angular velocity was set to 120o/s and 180o/s in the

isokinetic test.

Limitations

1. The power measured in isokinetic test was specific to the

extensors and flexors of the upper thigh at the specific

angular velocities of 120o/s and 180o/s.

2. Subjects were assumed to be familiar to the isokinetic

dynamometer in the test.

Instruments

Humac Norm Isokinetic dynamometer (HUMAC NORM, CSMI, Boston,

USA) and cycling dynamometer (Monark, Vansbro, Sweden) were

used for assessing maximal anaerobic power of the lower body

and warming up. The digital data about the isokinetic

reciprocal knee extension and flexion was stored and further

analyses in the Humac2004 software program in computer.

Measurement

Body weight (in kg) and height (m) were measured. Peak

torque in (Nm) and peak power (W) at 120o/s and 180o/s were

assessed by the isokinetic dynamometer.

Data analysis

SPSS vision 15.0 (SPSS Inc., Chicago, IL) as also used.

Descriptive data such as peak torque and peak power were

expressed by mean values with standard deviation. Furthermore,

Pearson Product Moment Correlation was calculated the

correlation of the MAP of the lower body in between isokinetic

and MST. The level of significance was set p < 0.005.

The following of statistical hypotheses were examined in

the first part of study:

1. There would be no significant correlation between the total

leg power of both legs and maximal anaerobic power output

in Margaria-Kalamen Stair-run Test.

Margaria-Kalamen Stair-run Test

Procedures

MST is a universal test of assessing the maximal anaerobic

power of the lower body. MST was conducted at the stairs of

the Shaw Campus in the Hong Kong Baptist University except on

the rainy day. The area was open to students with a shelter

and lighting as well as electricity supply. The usage of the

stairs was quite low and this ensured MST in the present study

was undergone safety and without disturbing others.

The Margaria-Kalamen stair-run test protocol (Kalamen,

1968) was employed. Subjects were asked to take a 6 m approach

run for speeding up before reaching the first step of the

staircase. 3 steps of stair climbing were done as quickly as

possible. 3 staircases were climbed for each step. Time

traveled between the 3rd step and 9th step was recorded (see

Appendix B).

Participants were instructed to wear comfortable clothing

and sports shoes. Body weight was obtained in nearest 0.1 kg.

Five practical trials were given to the subject habituate the

stair-run for warming up. 3 minutes of rest was taken prior

to test. Three trials were performed by the subject and 2

minutes of rest was provided after each trial. The traveled

times were recorded in the three trials.

5 minutes of rest was taken after that in between the MST

alone and with external weight (EW) of 28% of body weight (BW).

The stair-run test was then performed similarly, starting with

five practical trials with EW of 28% BW of the subject. Finally,

both the shortest times among the three trials with or without

external load were used to measuring the maximal anaerobic

powers of the subject. The order of applying the MST alone and

MST with EW of 28% BW was randomized. The MAP in MST alone was

correlated to the total leg power in isokinetic knee flexion

and extension test for part one of the study. Meanwhile the

MAP in both MST alone and with EW of 28% BW were compared for

part two of the study.

Delimitations

1. 20 young adults who were aged between 19 and 25 and

physically active at the universities in Hong Kong were

invited to be the subjects.

2. MST was undergone in f ield at the Shaw Campus of the Hong

Kong Baptist University.

3. Ankle weights for the training of athletes were used as

the external load. The mode of carrying external load was

the combined front and backpack.

Limitations

1. Data were collected in different days and periods of time.

2. All of the subjects were assumed biological matured as well

for motor ability.

3. The vertical height and horizontal distance of the stairs

in Shaw Campus of the Hong Kong Baptist University was

assumed to be as same as the original design of MST.

4. The effect of external loading (e.g. the centre of mass)

was assumed to be the same to every subject.

Instruments

Ordinary staircase was used at the Shaw Campus of Hong Kong

Baptist University. The dimensions of each step of the

staircase were approximately 15 cm high and 18 cm deep. Two

pressure time-mats were placed on the 3 rd and 9 th stair and used

to recording the time, to the nearest 0.001s between steps

automatically on an oscillographic recorder. A specially

constructed vest which could be externally loaded in a variable

manner with a number of ankle weights which consisted of lead

powders. The weights were equally distributed between the

chest and back (Caiozzo & Kyle, 1980). (See Appendix B)

Measurement

The maximal anaerobic power (MAP) was calculated by the

product of body weight (BW), gravitational acceleration, and

the vertical distance divided by the shortest traveled time

between the 3rd and 9th stairs in tests with or without external

load. The power output was then converted in to watts (W).

(s) time819)(m distance vertical)kg(BW

)W(MAP1−××

=ms .

Data analysis

SPSS vision 15.0 (SPSS Inc., Chicago, IL) as used in data

analysis. Descriptive data such as weight, external load,

traveled time and maximal anaerobic power were expressed by

mean values with standard deviation. Furthermore, paired

sample t-test was proceeded to compare the mean of peak power

and the traveled time between original MST and that with

external load of 28% of body weight within both genders. The

level of significance was set p < 0.05.

The following of statistical hypotheses were examined in

the second part of study:

1. There would be no significant difference in the mean of

power output between original Margaria-Kalamen Stair-run

Test and that with external weight of 28% of body weight

within both genders.

Chapter 4

ANALYSIS OF DATA

Twenty Subjects (Ten males and ten females) from the Hong

Kong Baptist University were invited to participate in the

study. Three of the male subjects dropped out because of their

personal reasons and their data have been excluded. The first

part counted on the performance of the seventeen subjects in

the tests to examine the validity of Margaria-Kalamen

Stair-run test (MST) assessing the maximal anaerobic power

(MAP) while the second part of investigating the effect of

external loading on MAP in MST analyzed the data within the

male (n = 7) and female (n = 10) groups separately.

Part One:

Validity of Margaria-Kalamen Stair-run test assessing the

maximal anaerobic power.

Results

The physical characteristics of the participants are shown

in Table 1.

Table 1

Physical Characteristics and the power of the knee extensors

and flexors in isokinetic knee extension and MST of the

participants (n=17)

Variables Minimum Maximum Mean ± SD

Age (years) 19 25 21.1 ± 1.60

Height (m) 156 172 164 ± 5.4

Body Weight (kg) 42.8 64.1 55.0 ± 6.40

Total Power of Knee Extensors

in Isokinetic Test (W)

191 486 289 ± 89

Total Power of Knee Flexors

in Isokinetic Test (W)

126 312 190 ± 58

Total Leg Power

in Isokinetic Test (W)

317 798 479 ± 144

Power in MST (W) 569 1109 832 ± 89

The Pearson correlation of the MAP of the lower body in between

isokinetic knee extension test and MST was shown in Table 2.

These two tests of measuring the MAP of the lower body are highly

correlated and their relationship was shown in Figure 1 below.

Table 2

Pearson’s correlation test of the MAP of the lower body

resulting from MST with isokinetic knee extension test (N=17)

Method r p

MST 0.869** 0.000

** Correlation is significant at the 0.01 (2-tailed).

Figure 1

Scatter-plots showing the Correlation between MST and the

isokinetic knee extension test of assessing the MAP of the lower

body for all subjects (n=17).

56957762665165571071576677677798110011047107010751109

Power in MST (W)

317

330

334

335

361

372

388

408

495

541

596

609

616

645

798Total Leg Power in Isokinetic Test (W)

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

Discussions

The present study resulted in a positive significant

correlation of measuring the maximal anaerobic power of the

lower body part in between MST and isokinetic knee extension

test (r = 0.869, p < 0.05). This showed that MST was highly

valid to assess the maximal anaerobic power of the lower body

(both the knee extensors and knee flexors) in young adults.

Knee extensors and flexors were the antagonists and greatly

contributed to leg extension and flexion in climbing stairs

at fast as possible in MST. Although MST bore the body weight

as the load while isokinetic knee extension test did not, the

result of the highly positive correlation between the two tests

implied that the body weight did not impair the validity of

MST assessing the maximal anaerobic power of the lower body

(MAP) although a recent study believed that body weight (size)

could confound the outcome of the MST (Nedelikovic, Mirkov,

Pazin, 2007). In our study, the angular velocities of 120o/s

and 180o/s with 5 repetitions for both legs were used in the

isokinetic knee extension test. Such a high correlation might

be attributed to a similar angular velocity about the knee joint

during the knee extension and flexion in MST. Caiozzo & Kyle

(1980) suggested other factors affecting the leg power output

such as stair angle, step height and leg length as well as the

motor skill. Not only the body weight, were these factors also

believed to affect the angular velocity of the leg extension

and flexion about the knee joint in running stairs. Another

possible reason for such a high correlation referred to the

instability of the body due to one leg support only during

stair-run. Hong and Li (2005) indicated the vastus laterlis

of the quadriceps of the supporting leg were activated and

dominated the power production for pulling up the body.

The learning effect of running stairs in MST was possibly

eliminated by providing 3 to 5 times of trials for the subjects

familiar to the stair climbing skill before the test. It began

when the traveled times were kept constantly low throughout

the trials. However, there was a limitation of a few of subjects

who were still getting used to the stair-run skill after trials.

Therefore, the best traveled time was used to calculate the

lower leg power in MST. In the isokinetic knee extension test,

it started with randomized angular velocities and different

sides of leg to avoid the order effect. Another limitation would

be the small number of subjects being assessed in the study.

Part Two:

Effect of external loading of 28% of body weight on maximl

anaerobic power in Margaria-Kalament Step-run Test.

Results

The physical characteristics of the male and female

participating in the Margaria-Kalamen Stair-run Test (MST) as

well as the same test with external loading are shown in Table

3.

Table 3

Physical Characteristics of the male (n=7) and female (n= 10)

participants in MST

Group Variable Min Max Mean ± SD

Male Age (years) 21 25 22.1 ± 1.46

Height (m) 164.0 172.0 168 ± 2.7

Body Weight (kg) 52.7 64.1 59.3 ± 3.93

Female Age (years) 19 22 20.3 ± 1.25

Height (m) 156 169 160 ± 4.1

Body Weight (kg) 42.8 63.8 52.0 ± 6.20

The descriptive data in MST alone and EW of 28% BW of male and

female participants were summarized in Table 4.

Table 4

Descriptive data of Males (n = 7) and Female (n = 10) in between

the Margaria-Kalamen Stair-run tests (N=7)

TW: Total Weight

BTT: Best Traveled Time

Group Variable Method Min Max Mean ± SD

Male TW(kg) MST 64.1 52.7 59.3 ± 3.9

MST with EW 66.6 81.2 75.3 ± 4.9

BTT(s) MST 0.372 0.480 0.430 ± 0.340

MST with EW 0.412 0.510 0.460 ± 0.358

MAP (W) MST 981 1109 1047.0 ± 44.0

MST with EW 1155 1390 1246.0 ± 88.4

Female TW(kg) MST 42.8 63.8 52.0 ± 6.2

MST with EW 54.4 83.0 66.4 ± 8.5

BTT(s) MST 0.508 0.671 0.579 ± 0.526

MST with EW 0.544 0.717 0.638 ± 0.061

MAP (W) MST 569 777 682.2 ± 78.5

MST with EW 665 900 792.7 ± 81.3

Results of the pair-test in MST alone and with EW of 28% BW

within male and female subject groups were summarized in Table

5. There were significant mean difference on MAP, traveled time

and the total amount of weight used in between the two tests.

Table 5

Paired t-tests of Maximal Anaerobic Power (MAP), Traveled Time,

and Total Weight of Males (n = 7) and Female (n = 10) in between

the Margaria-Kalamen Stair-run tests

Group Method Mean ± SD (W) t p

Male MST 1047.0 ± 44.0

MST with EW 1246.0 ± 88.4

6.82 0.00*

Female MST 682.2 ± 78.5 4.55 0.00*

MST with EW 792.7 ± 81.3

p < 0.05, one-tailed.

In table 6, there was no statistically significant mean

difference between the external weight used in practical and

the expected external load of 28% of body weight in male and

female groups respectively by the one-sample test (t = 2.246

in male, t = 0.559 in female, p > 0.05).

Table 6

One-Sample Test between the weight of the external load used

in practical (EW/BW %) and the expected percentage of the

external load of 28% of body weight in MST (n = 7 in males,

n = 10 in females)

Group Mean ± SD Mean Difference t p

Male 27.3 ± 0.8 -0.70 -2.24 0.07

Female 28.1 ± 0.6 0.10 0.56 0.59

*p

greater than the MST ( male: t = 6.82, p = 0.00, N = 7; female:

t = 4.55, p = 0.00).

Mayhew, Schwegler and Piper (1986) suggested that MST was

a mass-power test rather than a speed power test due to the

extensive involvement of the body weight in the calculation

of MAP. According to the standard equation of MAP in MST,

(s) timeledbest trave The819)(m distance vertical)kg( Weight Total

)W(MAP1−××

=ms .

,

the amount of total weight was 20 to 36 times of the reciprocal

of the best traveled time within male group and 24 to 41 times

within female group in original MST. It became 29 to 46 times

within male group and 30 to 60 times within the female group

in MST with EW of 28% BW. The influence of the total weight

on the standard formula of MAP became greater for EW of 28%

BW and therefore resulted in a greater MAP.

Another possible reason for the greater MAP in MST with

EW of 28% BW referred to the change of gait pattern. Caiozzo

and Kyle (1980) speculated either the stride length or the

speed-load interaction became more optimal for MST with

external loading but without any further explanations. Hong

and Li (2005) found that a greater ground reaction force was

generated under the influence of external load in stair walking.

This might also be true for running stairs. The gait cycle of

stair-run involved: i) take off phase, ii) flight phase, iii)

land and support phase. Mcfadyen and Winter (1988) reported

that there were two peak force in one gait cycle. The second

peak force occurred at extending ankle joint of the lead foot

while the first peak force occurred immediately after the

contralateral foot took off and began to swing. The total weight

was only supported by the lead foot on a stair. This caused

the greatest instability of the body (at ankle, knee and hip

joints) during the stair-run. As a result, the knee extensors

were greatly activated in order to counter the rotation due

to the instability. Hong and Li (2005) discovered that the peak

distal-proximal contact force was three to six times of BW and

it was significantly higher than that in the normal ascent

without EW. The neuromuscular system activated to provide a

greater peak force under the EW of 28% BW possibly resulted

in a greater power output in MST.

As MST required a high level of locomotors skills, three

trials were given to subjects to practice in order to eliminate

the learning effect. However, there were individual

differences in motor skills. Few subjects jumped rather than

ran up the stairs and their MAP of the lower body might not

be true. Before running stairs, there was a 10m approaching

run. The inertia of moving forward horizontally was greater

due to the increase of inertial mass with EW of 28% BW. This

led to an optimal take off angle for exerting a greater MAP

of the lower body in MST.

In the present study, randomizing the order of the MST alone

and with EW of 28% BW eliminated the order effect. However,

there might be an interaction effect if MST with EW of 28% BW

was taken first. It possibly activated the neuromuscular

system initially and might result in a higher MAP in MST after

that. This could be reduced by a longer resting period of at

least 5 minutes between the tests. There was limitation in

controlling the EW exactly 28% BW in practical due to the short

duration of the study or toleration of the subjects. The mean

differences of the EW in practical to the 28% BW were -0.70

within male subject group and 0.10 within female. There were

no significant differences between the EW in practical and

expected EW of 28% BW.

The present study statistically demonstrated that EW of

28% BW resulted in a greater MAP of the lower body for both

male and female subjects in MST than the original. However,

few subjects especially the female found difficulties in both

physically and psychologically of running stairs with EW of

28% of BW. A lighter load, such as EW of 19% BW, might be more

appropriated and safety to them.

Chapter 5

SUMMARY AND CONCLUSION

The first part of the study attempted to examine the

validity of the Margaria-Kalamen Stair-Run Test (MST)

assessing the maximal anaerobic power (MAP). Investigating

whether the body mass would impair in MST, the part of study

compared the MAP of the lower body in MST in field and total

leg power from isokinetic knee extension test among the

seventeen university students.

The second part of the study attempted to investigate the

effect of the external weight (EW) of 28% body weight (BW) on

MAP in MST. Whether the EW of 28% BW would result in a greater

MAP, this part of study compared MAP in between the MST alone

and with EW of 28% BW within the young male ( n = 7) and female

(n = 10).

Summary of Results

The first part of the study showed a significantly positive

correlation between the MAP of the lower body in MST and the

total leg power in isokinetic knee extension test ( r = 0.869,

p < 0.05). The second part of the study demonstrated the MAP

in MST with EW of 28% BW was significantly greater than that

in MST alone within the male and female groups (male: t = 6.82,

female: t = 4.55, p < 0.05, one-tailed).

Conclusions

The first part of study justifies that MST is a highly valid

test of assessing the MAP of the lower body and the body mass

does not impair the power output. The second part of study shows

that EW of 28% BW results in a greater MAP in MST than the

original MST.

Recommendations of Further Study

Firstly, previous and present studies investigated the

effect of EW of 28% BW on MAP in MST among the athletes and

young active adults only. Further study can focuses the effect

of EW on MAP in other populations such as the overweight or

obese. However, a lighter load was recommended to utilize for

those who are heavy. Secondly, a lighter EW of 19% BW can be

studied and compared to the MAP with EW of 28% BW for young

female adults. Thirdly, there are no standardized methods of

load carriage in MST. Further study can compare different types

of load carriage during stair-run under the biomechanical

analysis in addition to the effect of different t ypes of load

carriage on MAP in MST.

REFERENCES Alangari, A.S., & Al-Hazzaa, H.M. (2003). Normal isometric

and isokinetic peak troques of hamstring and quadriceps muscles in young adult Saudi males. Neurosciences, 9 (3), pp. 165-170.

Alexander, M.J. (1989). The relationship between strength and

sprint kinematics in elite sprinters. Canadian Journal of Sport Science, 14, pp. 148-157.

Ashley, C.D., & Weiss, L.W. (1994). Vertical jump performance

and selected physiological characteristics of women. Journal of Strength and Conditioning Research, 8, pp. 5-11.

Augustsson, J., Esko, A., Thomeé, R., & Svantesson, U. (1998).

Weight training of the thigh muscles using closed vs. open kinetic chain exercises: comparison of performance enhancement. Journal of Orthopaedic and Sports Physical Therapy, 27, pp. 3-8.

Barany, M. (1967). ATPase activity of myosin correlated with

speed of muscle shortening. Journal of General Physiology, 50, pp. 197-218.

Bigland-Ritchie, B., Jones, D.A., Hosking, G.P., & Edwards,

R.H.T. (1978). Central and peripheral fatigue in sustained maximum voluntary contractions of human quadriceps muscle. Clinical Science and Molecular Medicine, 54, pp. 609-614.

Bouissou, P., Estrade, P.Y., Goubel, F., & Guezennec, C.Y.

(1989). Surface EMG power spectrum and intramuscular pH in human vastus lateralis muscle during dynamic exercise. Journal of Applied Physiology, 67, pp.1245-1249.

Brown, L.E., & Whitehurst, M. (2000). Load Range. In Brown,

L.E. (Ed.), Isokinetics in human performance (pp. 97-121). Champaign, IL: Human Kinetics.

Burdett, R., & Swearingen, J.V. (1987). Realiability of isokinetic muscle endurance test. Journal of Orthopaedic and Sports Physical Therapy, 11, pp.155-157.

Caiozzo, V.J.,& Kyle, C.R. (1980). The effect of external load

upon power output in stair climbing. European Journal of Applied Physiology, 44, pp. 217-222.

Cronin, J.,& Sleivert, G. (2005). Challenges in understanding

the influence of maximal power training on improving athletic performance. Sports Medicine, 35(3), pp. 213-234.

Davies, C.T.M., & Young, K. (1984). Effects of external

loading on short term power output in children and young male adults. European Journal of Applied Physiology, 52, pp. 351-354.

Davis, D.S., Briscoe, D.A., Markowski, C.T., Saville, S.E.,

& Taylor, C.J. (2003). Physical characteristics that predict vertical jump performance in recreational male athletes. Physical Therapy in Sport, 4, pp. 167-174.

Davies, G.J., Heiderscheit, B., & Brinks, K. (2000). Test

interpretation. In Brown, L.E. (Ed.), Isokinetics in human performance (pp. 3-24). Champaign, IL: Human Kinetics.

Destaso, J., Kaminski, T.W., & Perrin, D.H. (1997).

Relationship between drop vertical jump heights and isokinetic measures utilizing the stretch-shortening cycle, Isokinetics and Exercise Science, 6, pp. 175-179.

Faulkner, J.A., Claflin, D.R., & Cully, K.K. (1986). Power output of fast and slow fibers from human skeletal muscles. In Jones, N.L., McCartney, N., McComas, A.J. (Eds.), Human muscle power (pp. 81-93). Champaign, IL: Human Kinetics.

Hill, A.V. (1938). The heat of shortening and the dynamic

constraints of muscle. Proceedings of the Royal Society of London. Series B. Biological Science, B126, pp. 136-195.

Hong, T. (1999). Research on relationship between load and power in anaerobic power step test. Sports and Science, 20 (1),pp. 34-37.

Hong, T.,& Liao, A. (2004). The study progress of margarita

anaerobic power step test. Journal of Physical Education, 11 (2), pp. 51-53.

Hong, Y.,& Li, J.X. (2005). Influence of load and carrying

methods on gait phase and ground reactions in children’s stair walking, Gait and Posture, 22, pp. 63-68.

Husky,T.,& Mayhew, J.L., Ball, T.E. (1989). Factors affecting

anaerobic power output in the Margaria-Kalamen test. Ergonomics, 32 (8), pp. 959-965.

Iossifidou, A., Balzopoulos, V., & Giakas, G. (2005).

Isokinetic knee extension and vertical jumping: Are they related? Journal of Sports Sciences, 23 (10), pp. 1121-1127.

Johnson, J., & Siegel, D. (1978). Reliability of an isokinetic

movement of the knee extensors. Research Quarterly, 49, pp.88-90.

Kalamen, J.L., 1968. Measurement of maximum muscular power

in man, Doctoral dissertation, Ohio State University, Coloumbus, OH

Keating, J.L., & Matyas, T.A. (1996). The influence of subject

and test design on dynamometric measurements of extremity muscles. Physical Therapy, 76 (8), pp. 866-889.

Kitagawa, K., Suzuki, M., & Miyashita, M. (1980). Anaerobic

power output of young obese men: comparison with non-obese men and the role of excess fat, European Journal of Applied Physiology, 43, pp. 229-234.

Kovaleski, J.E., & Heitman, R.J. (2000). Testing and training the lower extremity. In Brown, L.E. (Ed.), Isokinetics in human performance (pp. 171-195). Champaign, IL: Human Kinetics.

Kraemer, W.J., Mazzetti, S.A., Raamess, N.A., Fleck, S.J.

(2002). Specificity of training modes. In Brown, L.E. (Ed.), Isokinetics in human performance (pp.25-41). Champaign, IL: Human Kinetics.

Kyle, C.R., & Caiozzo, V.J. (1985). A comparison of the effect

of external loading upon power output in stair climbing and running up a ramp. European Journal of Applied Physiology, 54, pp. 99-103

Legg, S.J. (1985). Comparison of different methods of load

carriage, Ergonomics, 28, pp. 197-212 Legg, S. J., & Mahanty, A. (1985). Comparison of five modes

of carrying a load close to the trunk.Ergonomics 28, pp. 1653–1660.

Liebermann, D.G.,& Katz, L. (2003). On the assessment of

lower-limb muscular power capability, Isokinetic and Exercise Science, 11, pp. 87-94.

Markovic, G., & Jaric, S. (2005). Scaling of muscle power to

body size: the effect of stretch-shortening cycle. European Journal of Applied Physiology, 95, pp. 11-19.

Martin, P.E., & Nelson, R.C. (1986). The effect of carried loads on the walking patterns of men and women. Ergonomics, 29, pp.1191-1202.

Mayhew, J.L., Schwegler, T.M.,& Piper, F.C. (1986).

Relationship of acceleration momentum to anaerobic power measurements. The Journal of Sports Medicine and Physical Fitness, 26 (3), pp. 209-213.

McFadyen, B.J.,& Winter, D.A. (1988). An integrated biomechanical analysis of normal stair ascent and descent. Journal of Biomechanics, 21, pp. 733-744.

Miller, R.G., Giannini, D., & Milner-Brown, H.S. (1987).

Effects of fatiguing exercise on high-energy phosphates, force, and EMG: evidence for three phases of recovery. Muscle Nerve, 10, pp. 810-821.

Mira, A.J., Carlisle, K.M., & Greer, R.B. (1980). A critical

analysis of quadriceps function after femoral shaft fracture in adults. The Journal of Bone and Joint Surgery, 62, pp. 61-67.

Murray, P.M., Gardner, G.M., Mollinger, L.A. (1980) Strength

of isometric and isokinetic contractions. Physical Therapy, 64, pp.412-419.

Nedeljkovic, A., Mirkov, D.M., Pazin, N., & Jaric, S. (2007).

Evaluation of Margaria staircase test: the effect of body size, European Journal of Applied Physiology, 100, pp. 115-120.

Osternig, L.R. (2000). Assessing human performance. In Brown,

L.E. (Ed.), Isokinetics in human performance (pp.196-208). Champaign, IL: Human Kinetics.

Power, S.K.,& Howley, E.T., (2004). Exercise physiology:

theory and application to fitness and performance (5th ed.). NY: McGray-Hill.

Saliba, L., & Hrisomallis, C. (2001). Isokinetic strength

related to jumping but not kicking performance of Australian footballers. Journal of Science and Medicine in Sport, 4, pp. 336-347.

Sargeant, A.J. (1998). The determinants of anaerobic muscle function during growth. In Praagh, E.V. (Ed.) Pediatric anaerobic performance (pp.97-117). Champaign, IL: Human Kinetics.

Schwegler, T.M., Mayhew, J.L., & Piper, F.C. (1985). Effects

of acceleration momentum on anaerobic power measuremens, Carnegie Research Papers, 1, (7), pp. 23-26.

Scott Davis, D., Briscoe, D.A., Markowski, C.T., Saville,

S.E., & Taylor, C.J. (2003). Physical characteristics that predict vertical jump performance in recreational male athletes. Physical Therapy in Sport, 4, pp.167-174.

Slocker de Arce, A., Carrascosa Sánchez, J., & Fernandez

Camacho, F.J. (2001). Isokinetic evaluation of the healthy knee: Position of the joint at the peak torque. Isokinetics and Exercise Science, 9, pp.151-154.

Stratford, P. (1991). Reliability of a peak knee extensor and

flexor torque protocol: a study of post ACL reconstructed knees. Physiotherapy Canada, 43, pp.27-30

Taylor, N.A.S., Cotter, J.D., Stanley, S.N., & Marshall, R.N.

(1991). Functional torque-velocity and power-velocity characteristics of elite athletes. European Journal of Applied Physiology, 62, pp. 116-121.

Timm, K.E., & Fyke, D. (1993). The effect of test speed sequence

on the concentric isokinetic performance of the knee extensor muscle group. Isokinetics and Exercise Science, 3 (2), pp. 123-128.

Tsaklis, P. (2002) Isokinetic evaluation of the knee extensors

and flexors anaerobic capacity. Isokinetic and Exercise Science, 10, pp.69-72.

Tsiokanos, A.T., Kellis, E., Jamurtas, A., & Kellis, S. (2002). The relationship between jumping performance and isokinetic strength of hip and knee extensors and ankle plantar flexors. Isokinetics and Exercise Science, 10, pp. 107-115.

Viitasalo, J.T., & Komi, P.V. (1978). Force-time

characteristics and fiber composition in human leg extensor muscles. European Journal of Applied Physiology, 40, pp. 7-15

Weiss, L.W. (2000). Multiple-joint performance over a

velocity spectrum. In Brown, L.E. (Ed.), Isokinetics in human performance (pp.196-208). Champaign, IL: Human Kinetics.

Wilson, G., & Murphy, A. (1995). The efficacy of isokinetic,

isometric and vertical jump in exercise science. Australian Journal of Science and Medicine in Sport, 27, pp. 20-24.

Zhao, G., & Hong, T. (2001). Comparing research on anaerobic

power step-test of male and female college student sportsman. Journal of Qingdao University, 14(3), pp. 91-94.

Appendix A

Consent Form to subjects

Hong Kong Baptist University

Informed Consent for the Power Tests of Lower Limb In order to assess investigating i) the validity of MST assessing the maximal anaerobic power; ii) the effects of external loading on maximal anaerobic power in Margaria-Kalamen Stair-run Test (MST), the undersigned hereby voluntarily consents to involve in the following tests:

1. Isokinetic Reciprocal Knee Extension and Flexion Test 2. Margaria-Kalamen Stair-run Test

Explanation of the Tests 1. Isokinetic Reciprocal Knee Extension and Flexion Test

The measurement of the average power requires knee extension and flexion for 5 repetitions in maximum intensity by right and left legs respectively. The angular velocities used are 120o/s and 180o/s.

2. Margaria-Kalamen Stair-run Test The measurement of the traveled time requires running up 12 stairs with 4 steps as quick as possible both with and without external loading of 28% of body weight.

Risk and Discomforts 1. Isokinetic Reciprocal Knee Extension and Flexion Test

Warm up is essential to the muscle before the test. There is a very slightly possibility of pulling the muscle fibers or staining alignments of your tested leg during the isokinetic knee extension and flexion.

2. Margaria-Kalamen Stair-run Test

During the stair-climbing, you may experience a discomfort pressure at your knee joint by both your body weight and external load. There is also a risk of knee injury in the test.

Inquires Questions about the detailed procedures used in the leg power tests are encouraged. If the participant has any questions or needs as well as information, please ask the test administrator to explain further. Freedom of Consent The participant’s permission to participate is voluntary and the participant is free to stop the test at any point, if he or she so desires. In signing this consent form, I, _____________________ (Name of participant), affirm that I have read this form entirely and have understood the description of the testing procedures, risks and discomforts as well as the opportunity to ask questions regarding to the power tests which have been answered in satisfactory. ________________________ _____________________ (Signature of participant) (Date) ________________________ _____________________ (Person administering tests) (Date)

APPENDIX B

Margaria-Kalamen Stair-run Test (MST)

The following figures show the set up of the MST including the approach run, timer, and the dimensions of stair-case used and mode of external load carriage

Figure 1. The setup of the MST (Saggital Plane)

Figure 2. Timer Figure 3. Path for Approach Run

Starting line

Figure 4. The staircase used and the locations of the p ressure time mats (Frontal Plane)

Table 1 The dimensions of the stairs

Stair 1st 2nd 3rd 4th 5th 6th 7th 8th 9th

Height (m) 0.10 0.10 0.12 0.13 0.13 0.13 0.13 0.13 0.13

1st step (0.39 m) 2nd step (0.39 m)

Deep (m) 0.24 0.25 0.25 0.25 0.25 0.25 0.25 0.26

1st Step (0.75 m) 2nd Step (0.76 m)

Vertical Traveled distance (3rd to 9th Step), h: 0.78 m

Gradient of the stairs: 27.3o

2nd Pressure pad at the 9th step

1st Pressure pad at the 3rd Step

Mode of External Load Carriage:

Front- and Backpack

Figure 5. Front side

Figure 6. Back side

Figure 7. Lateral side

Appendix C. Data Collection Form –Isokinetic reciprocal knee extension and flexion test

Isokinetic Power (Left) Power (Right) Extensors Flexors

Name Gender Age Height (m) BW (kg) Extensor (W) Flexor (W) Extensor (W) Flexor (W) Total Power (W) Total Power (W)

Data Collection Form –Margaria-Kalament Stair-Run Tests

Stair Test Original With EW Original With EW

Name Gender Age BW (kg)

BW + EW (kg)

Trial 1 (s) Trial 2 (s) Trial 3 (s) BEST T(s) Trial 1 (s) Trial 2 (s) Trial 3 (s) BEST T (s) Power (W) Power (W)