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Unit 4 – Training to Improve Performance AREA OF STUDY 1 – WHAT ARE THE FOUNDATIONS OF AN EFFECTIVE TRAINING PROGRAM?
Understanding Fitness
Defining Fitness
In a broad sense fitness relates to our health and well being. Feeling well is an acceptance of our current state or condition.
Dimensions of WellnessSocialSpiritualPhysicalEmotionalMentalEnvironmentalFinancial
Definitions of Physical Fitness
“Fitness for life” encompasses fitness for work, for leisure and recreational activities, for family life and parenthood, and fitness to cope with emergencies. Being fit allows us to carry out every day activities without undue fatigue and leaving us with sufficient energy to participate in physical activities and deal with emergencies.
To attain and maintain fitness requires adequate and balanced nourishment, adequate and varied exercise, adequate sleep, avoidance of excess in using social drugs, stimulation without excessive stress, and psychosocial well-being.
“Fitness for sport” is far more specific and is determined by the demands of the sport and the capacities of the individual.
The Fitness Components
HEALTH RELATED FITNESS COMPONENTS
Skill Related Fitness Components
• AEROBIC POWER
• BODY COMPOSITION
• MUSCULAR STRENGTH
• MUSCULAR ENDURANCE
• FLEXIBILITY
SKILL RELATED FITNESS COMPONENTS
FITNESS
• ANAEROBIC CAPACITY
• MUSCULAR POWER
• SPEED
• AGILITY
• BALANCE
• REACTION TIME
• COORDINATION
Health Related Fitness ComponentsAEROBIC CAPACITY, MUSCULAR STRENGTH, MUSCULAR ENDURANCE,BODY COMPOSITION AND FLEXIBILITY
Aerobic PowerThe maximum rate of energy production from the aerobic energy system (i.e. energy produced in the presence of oxygen). VO2 Max is a measure of an athlete’s aerobic fitness – it is their max volume of oxygen consumption (ml/kg/min).
Maximal Oxygen Uptake (mL/kg/min) Non athletes
Age Males Females10 - 19 47 – 56 38 - 4620 - 29 43 – 52 33 - 4230 - 39 39 – 48 30 - 3840 - 49 36 – 44 26 - 3550 - 59 34 – 41 24 - 3360 - 69 31 – 38 22 – 3070 - 79 28 – 35 20 - 27
Maximal Oxygen Uptake (mL/kg/min) Athlete
Males FemalesBaseball/Softball 48 – 56 52 - 57
Basketball 40 – 60 43 - 60Cycling 62 – 74 47 - 57Football 42 - 60 26 - 35
Gymnastics 52 – 58 36 - 50Rowing 60 – 72 58 - 65
Skiing (nordic) 65 – 94 60 - 75Soccer 54 – 64 50 - 60
Swimming 50 – 70 40 - 60Discus 42 – 55
Running 60 – 85 50 - 75Volleyball 40 - 56
Weightlifting 38 - 52 Wilmore and Costill 2005
Factors Affecting Aerobic Power
Healthy lungs and respiratory muscles will allow for efficient breathing and lung diffusion.
Size of heart – an aerobically trained athlete will have a larger left ventricle and increased stroke volume.
Cardiac Output - an increased Cardiac Output will improve aerobic power due to increased delivery of blood and therefore O2 and nutrients. HEART RATE X STROKE VOLUME = CARDIAC OUTPUT
Blood volume – aerobic training increase blood volume. Haemoglobin levels will allow for increased oxygen carrying capacity. Elasticity of blood vessels - vasodilation of elastic blood vessels will increase
blood flow to working muscles and therefore increase delivery of oxygen and nutrients.
Factors Affecting Aerobic Power
Number & size of mitochondria - increased number and size of mitochondria will increase aerobic respiration (converting oxygen & nutrients into ATP)
Gender – males generally have higher levels of Aerobic Power mostly due to a higher cardiac output.
Age - aerobic Power can peak at around age 30 and may deteriorate after this age due to decreases in max HR, Stroke Volume and extraction of O2 at the muscle cell.
Genetics – there are strong links between genetics and an individual’s aerobic power and ability to improve their aerobic power.
Body CompositionBody composition is defined as the percentage of fat, muscle, and bone in the body.Body composition will typically be displayed as either a percentage of fat (body fat percentage or %fat) or as a percentage of lean body mass (LBM).BMI (body mass index) categorises individuals into under, normal or over weight by dividing weight (in kg) by height (in m. squared)
Body Composition
Excess body fat hinders sport performance. Excess non essential body fat is related to injury, non adherence to training and
overall reduced athletic performance. A high body fat percentage acts as "dead weight" reducing speed and efficiency of movement.
Fat Free Mass - this consists of bones, muscles, connective tissue, organs, teeth and water.
Fat Mass Essential fat -for the body to function normally and healthily a certain amount of body
fat is required. This is called essential fat. For women the average amount of essential fat is 12% of bodyweight and for men it is 3%.
Non essential fat - this is the fat found in our adipose tissue.
0 5 10 15 20 25 30
Baseball
Basketball
Body Building
Cycling
Gymnastics
High/Long Jump
Rowing
Shot Putters
X Country Skiing
Sprinters
Swimming
Tennis
Triathlon
Volleyball
Average Body Fat Percentage of Athletes
Female
Male
Somatotypes
In the 1940s, Sheldon developed a theory that there are three basic body types, or somatotypes (based on the three tissue layers: endoderm, mesoderm, and ectoderm.
All possible body types are graded in a scale from 1 (low) to 7 (high), based on the degree to which they matched these types; with 4 as average).
ENDOMORPH
• soft body
• underdeveloped muscles
• round shape
MESOMORPH
• hard body, muscular body
• solid build
• rectangular shape
ECTOMORPH
• thin flat chest
• delicate build
• tall lightly muscled
Muscular StrengthMuscular strength is defined as the maximum amount of force that a muscle can exert against some form of resistance in a single effort.It is the peak force that a muscle can develop.
Factors Affecting Muscular Strength –Types of Muscle Contraction
There are three types of muscle actions :
1. ISOINERTIAL - muscle action where the load or resistance against the muscle is constant throughout the motion.
CONCENTRIC – the muscle length decreases.
ECCENTRIC – the muscle length increases.
2. ISOMETRIC – the muscle length remains unchanged ( gripping a racquet handle ).
3. ISOKINETIC – the resistance changes according to joint angle (requires specialised machines like the cybex & nautilus which allows maximum contractions through the full range of movement). Kicking a ball – the quadriceps
contract CONCENTRICALLYLowering a barbell – the biceps contract ECCENTRICALLY
Gripping a racquet handle –muscles in forearm contract
ISOMETRICALLY
Factors Affecting Muscular Strength – Muscle Size & Fibre Arrangement
Force generated by a muscle is related to cross sectional area of muscle. Greater cross sectional area – greater the force.
Fibre arrangements of muscles also influence force.
Parallel (fusiform) – the fibres are parallel to the long axis of the muscle and when the fibers contract together, the entire muscle shortens by the same amount. Suited to faster less forceful contractions.
Factors Affecting Muscular Strength – Muscle Size & Fibre Arrangement
Fusiform fibres - fibres run parallel to the long axis of the muscle eg biceps and are designed for speed of contraction.
Unipennate, bipennate & multipennate fibres-fibres lie at an angle to the long axis of the muscle and are designed for strong forceful contractions
Eg unipennate (calf) Eg bipennate (quads) Eg multipennate (deltoids)
ConvergentPectoralis major
Bi-pennateRectus femoris
Uni-pennateGastrocnemius
Factors Affecting Muscular Strength -Muscle Fibre Types
The three types of skeletal muscles are:-
Type I red fibres (slow oxidative) Type IIa red fibres (fast oxidative) Type IIb white fibres (fast glycolytic)
Long distance running
Middle distance
Sprinting
Characteristics of Muscle Fibres
Type I (slow oxidative) Type IIa (fast oxidative) Type IIb (fast glycolytic)Large amounts of myoglobin Large amounts of myoglobin Contain low myoglobin content
Many mitochondria Many mitochondria. Few mitochondria
Many blood capillaries Many blood capillaries Few blood capillaries
Generate ATP aerobically Rapid ATP production-oxidation Large amount of glycogen
Split ATP at a slow rate Split ATP at rapid rate Split ATP very quickly
Slow contraction velocity High contraction velocity Fatigue easily
Resistant to fatigue Resistant to fatigue High force production
Low force production intermediate force production High PC & glycogen stores
Low PC & glycogen stores High PC & glycogen stores Low triglyceride stores
High triglyceride stores Moderate triglyceride stores
Fibres and Contractions
Individual muscles are a mixture of three types of muscle fibres (type I and type IIa and b), but their proportions vary depending on the action of that muscle. It must be remembered that skeletal muscles, although a mixture, can only have one type of muscle fibre within a motor unit.
Weak contraction only the type I motor units will be activated - mainly for endurance activities.
Stronger contractions type IIa fibres will be activated or used to assist the type I fibres. Maximal contractions facilitate the use of type IIb fibres which are always activated last.
Muscle Fibre Distribution
There are no sex or age differences in fiber distribution, however, relative fibre types vary considerably from muscle to muscle and person to person.
Sedentary men and women (as well as young children) have 45% type 2 and 55% type I fibres. People at the higher end of any sport tend to demonstrate patterns of fibre distribution.
Endurance athletes show a higher level of type I fibres. Sprint athletes, on the other hand, require large numbers of type IIb fibres. Middle distance event athletes show approximately equal distribution of the two types. This
is also often the case for power athletes such as throwers and jumpers.
Length-Tension Relationship
Muscles are in a stretched state at rest which maximizes the ability of the muscle to contract when stimulated.
If the length of the muscle is shorter or longer than resting length then the force of muscle contraction is reduced.
Studies have shown that the optimal length of a muscle for a forceful contraction is that found at rest.
TensionLength
Length Tension Curve
Resting length
Speed of Contraction
Concentric contraction - as the velocity increases the force decreases.
Eccentric contraction - as the velocity increases there is an increase in force followed by a plateau (force does does not decrease - able to lower a heavier weight than we can lift).
At zero velocity the muscle is contracting isometrically and can produce a significant amount of force.
Increased velocity eccentric 0 Increased velocity concentric
Isometric contraction (Velocity is zero)
Force
Concentric contraction
Eccentric contraction
Velocity
Age and Gender
Strength increases from early childhood through adolescence to adulthood in both males and females.
Until puberty increases in muscular strength are similar for boys and girls – but due to males having increased levels of testosterone (key hormone in process of muscle building) they develop more muscle mass and cross-sectional area than females resulting in greater overall strength in males.
Strength peaks 25-30 years – plateaus until 45-50 years thendecreases due to:-• decreased muscle mass• loss of contractile properties
of the muscle• reduced activation of motor
units 0
20
40
60
80
100
120
6yo - 11yo 12yo - 19yo 20yo - 39yo 40yo - 59yo 60yo - 79yo
KG
Years
Grip Strength
Males
Females
Muscular EnduranceMuscular endurance is the ability of a muscle or muscle group to do repeated contractions against a less-than-maximum resistance for an extended period of time.
Factors Influencing Muscular Endurance
Capacity to delay onset of fatigue due to : fuel depletion
metabolic by-products
thermoregulation.
Muscle fibre type:- fast twitch fibres high levels of fatigue – low endurance capacity. slow twitch fibres low levels of fatigue – high endurance capacity.
FlexibilityFlexibility is defined as the ability to move joints or muscles through their full-range of motion.
Types of Flexibility
Static – range of motion under stationary conditions.
Dynamic – resistance to motion in a joint.
Factors Affecting Flexibility
Joint Structure Flexibility is partly determined by joint
type. ball & socket joints allow flexion,
extension, rotation, abduction and adduction.
hinge joints allow only flexion and extension.
Factors Affecting Flexibility
Soft Tissue Structures Soft tissue structures provide resistance
to movement. The relative contributions of soft tissue to
joint stiffness are:- joint capsule, including ligaments
(47%) muscles and their fascial sheaths
(41%) tendons (10%) the skin (2%)
Body and Muscle Temperature Increasing muscle and body
temperature increases elasticity of muscles and thus improves flexibility of joints.
Factors Affecting Flexibility
Age – Gender Flexibility decreases
with age as connectivetissues lose elasticity.
Females tend to bemore flexible than males – the activitiesfemales engage in promote flexibility.
0
5
10
15
20
25
30
35
6yo - 11yo 12yo - 19yo 20yo - 39yo 40yo - 59yo 60yo - 79yo
cm
Age
Sit and Reach
Males
Females
Skill Related Fitness Components
Anaerobic CapacityThe total amount of energy obtainable from the anaerobic energy systems (the combined capacity of the ATP-PC system and anaerobic glycolysis system). The amount of ATP that can be produced anaerobically during high intensity /short duration physical activity is finite.
Gender - Males have increased muscle mass, more strength and greater capacity of fast twitch fibres.
Muscle Fibre Type - A greater percentage of fast twitch fibres will increase anaerobic capacity.
Lactate tolerance - A greater tolerance to the accumulation of lactate in the muscle (usually brought about through training) will enable an athlete to continue exercise at high intensity using the anaerobic pathways for energy production.
Availability of fuel - Once stores of Phosphocreatine and glycogen are exhausted energy production using the anaerobic pathways can’t continue.
Factors Affecting Anaerobic Capacity
Muscular PowerMuscular Power is the ability to contract muscles with speed and force in one explosive act.The ability of a muscle or group of muscles to exert a maximum amount of force in the shortest period of time.
POWER = FORCE X VELOCITY
Factors Affecting Power
Force of contraction which is determined by:- frequency of motor unit stimulation number and size of motor units
recruited number of cross bridges in action muscle length – tension relationship
Velocity of contraction which is affected by the length of muscle. At high velocities the power of
muscle actions can decrease.
Muscle fibre type – fast twitch fibrescan produce higher forces in shorter periods of time so muscles with high percentages of fast twitch fibres will have an advantage in terms of the development of power.
SpeedSpeed is a measure of the ability to move all or part of the body as quickly as possible.Speed is the rate of motion determined by:
distance / time
Running speed =stride length X stride frequency
Anaerobic energy production - an efficient anaerobic energy system will produce ATP quickly.
Muscle fibre type - athletes with higher proportions of Fast Twitch Fibres in the leg muscles will be able to run faster.
Muscle activation - improved speed can occur with improved ability to recruit motor units through greater speed and frequency of nerve impulses as well as preferentially activating fast twitch fibres. This leads to faster contraction times.
Stiffness in connective tissue - allows for increased energy transfer. Resistance to fatigue – improved resistance to fatigue will allow higher speeds to be
maintained for longer.
Factors Affecting Speed
AgilityAgility is the ability to rapidly and accurately change the velocity or direction of the body in response to stimuli.It necessitates a combination of quick reactions & decision making, strength, power, speed, Flexibility, balance and co-ordination.
Factors Affecting Agility
Decision making - decision making in response to stimuli is important for good agility. Being able to read the play, recognize cues and make quick decisions will enhance agility.
Reaction time - the speed at which the athlete can detect stimuli, make a decision and send signals to the muscles to change
direction or velocity will affect agility. Strength & power - strong and powerful
muscles (particularly in the core) will enable controlled body positions to be adopted & maintained.
Speed - associated with rapid increases in velocity and changes in direction.
Flexibility - Restricted joint mobility with inhibit the ability to place the body in advantageous positions.
Balance - Good balance will allow the performer to take up controlled body positions when changing velocity or direction without falling over.
Co-ordination - Changing the direction and/or velocity of the whole body will require great co-ordination of body parts. All body parts must work in harmony to allow for good agility.
BalanceBalance is the ability to maintain equilibrium when stationary or moving.STATIC EQUILIBRIUM – when an object is stationary and all the forces or torques acting on it total to zero.DYNAMIC EQUILIBRIUM –when an object is moving with constant velocity and is not changing its state of motion (speed nor direction).
Vision - the eyes focusing on objects allows for a point of reference to position the body.
Vestibular function – vestibular receptors in the inner ear provide information related to movement and head position and are used to control balance.
Muscular function - strong and powerful muscles (particularly in the core) will enable balanced body positions to be adopted & maintained.
Proprioception - proprioceptors in the joints provide information about the body’s (and its parts) position in space and are used to control balance.
Factors Affecting Balance
Reaction TimeReaction Time is the ability to respond to a stimulus quickly.It is the time between the presentation of a stimulus and the commencement of movement.
Reaction Time
Reaction time is usually about 0.2 of a second.
In this time the performer has to : detect the signal interpret the information decide on a course of action send info to the muscles via
the CNS commence the movement
Reaction Time
Choice reaction time - the more choices possible means greater processing time and therefore slower reaction times.
Choice reaction time –should I pass dribble or shoot??
Simple reaction time - there is only one possible choice to the stimulus presented and reaction time will be very fast.
Simple reaction
time –gun = go
Number of choices – the greater the number of choices a performer has, the greater the reaction time.
Age - reaction times improve up until about 30 years (19-30yrs) fastest and then they gradually decrease as people age.
Sex - males have faster reaction times but they will deteriorate at a faster rate than females as they age.
Type of stimulus - reactions to sound (auditory) will be quicker than reactions to light (vision).
Stimulus intensity - reaction times improve as the intensity of the stimulus increases.
Anticipation – the ability to predict future events and thereby minimise reaction times.
Warning signals - the presence of warning signals will cut down reaction times(eg: ready – set – go).
Arousal - If the athlete is under aroused, performance will be sluggish as they are not ready to receive information and will be slow to react and move.
If the athlete is over aroused, performance will be affected by anxiousness, excitement or being over stimulated.
Factors Affecting Reaction Time
CoordinationCoordination is the ability to carry out a harmonious series of movements or motor tasks smoothly & efficiently.
Balance - co-ordinated movements are less likely if the athlete is off balance.
Rhythm - knowing when and how to time your movements are critical for co-ordinatedmovement.
Synchronisation - required so that the limbs can be moved in harmony to produce complex movements.
Kinesthetic awareness - knowing where your body is in relation to the environment.
Kinesthetic differentiation - knowing how much force to apply to achieve a desired outcome.
Practice - levels of co-ordination will improve with PRACTICE !!!
Factors Affecting Co-ordination
Revision Questions
1. The picture below represents which of the following fitness components:-
a. ballistic flexibility
b. dynamic flexibility
c. static flexibility
d. agility
2. Discuss how the following factors influence the application of strength:-
i. cross sectional area of muscle
Answer: greater cross sectional area the greater the force which is able to be exerted.
ii. muscle fibre type
Answer: higher percentage of fast twitch fibres the greater the force produced as they split ATP rapidly.
Revision Questions
3. The table below identifies some of the movements and skills performed by a hockey player.
The TWO most important fitness components are:-
a. aerobic capacity and agility
b. aerobic capacity and muscular endurance
c. anaerobic capacity and aerobic capacity
d. anaerobic capacity and agility
Movement/Skill Distance/Frequency
Sprinting 372m
Cruising 459m
Jogging 1147m
Walking 1112m
Striking 21
Change direction 87
Dribble 8
Revision Questions
4. A group of Year 8 students completes the Abdominal Curl test in which they are required to complete curl-ups at a rate of 20 per minute for a total of 60 curl-ups.
• Which fitness component is being tested?
Answer: muscular endurance
• What major group of muscles is being tested?
Answer: abdominals
5. What is the major fitness component required by the athlete’s pictured below?
Answer: cardiorespiratory endurance / aerobic power
Revision Questions
Which muscle fibre types are best suited to this type of activity?
Answer: type I red fibres, slow twitch, slow oxidative.
Outline TWO characteristics that make them suited to this type of activity.
Answer:
• large amount of myoglobin enables them to attract high levels of O2.
• dense capillary network provides large amounts of O2 to diffuse into muscle cells.
• high number of mitochondria enables large amounts O2 to be used to produce resynthesise ATP aerobically.