Basketball Free Throw: A Written Technical Reportknixfan.com/files/Awrittentechnicalreport.docx · Web viewBASKETBALL FREE THROW: A WRITTEN TECHNICAL REPORT23 Running head: BASKETBALL

Running head: BASKETBALL FREE THROW: A WRITTEN TECHNICAL REPORT 1

Basketball Free Throw: A Written Technical Report

Christian Del Piano

Montclair State University

Advanced Coaching Techniques

PEMJ-547

Dr. Steven Leigh

December 16, 2013

BASKETBALL FREE THROW: A WRITTEN TECHNICAL REPORT 2

Basketball Free Throw: A Written Technical Report

SUMMARY

As a summary of this technical report, a research participant with intermediate

basketball skills was asked to perform this study to observe the biomechanical effects in

performing a free-throw shot. The player was observed performing the free-throws, video

recorded and given feedback and appropriate adjustments based on biomechanical research,

video analysis, and my recommendations. After three days of practicing, the player made

appropriate adjustments to the free-throw attempt and was reevaluated in order to draw

conclusions and make recommendations based on biomechanical research and video feedback.

This study showed that when a player who attempts a free-throw shot and does not bend

appropriately at the hip, knee and ankle joints, the trajectory of the shot will be straighter than

a player who does bend at those joints properly. The free-throw shot percentage was

improved based on biomechanical adjustments (increased flexion and full extension) and the

video feedback. The player has confirmed that the research was useful and will be applied in

order to improve individual game play and coaching effectiveness. Further research will be

needed to identify the focus and concentration aspect of the free-throw approach.


INTRODUCTION

The game of basketball is played by two teams consisting of five players. A team

attempts to outscore their opponent by passing, bouncing, handling, or dribbling the basketball

into position for shooting the ball into their offensive basket. The game continues until either

team commits a violation or foul, at which time the fouled player attempts a free-throw or

possession of the ball changes (Mood, Masker, & Rink, 1991).

A “free-throw” is a type of shot awarded to a player after a foul or violation is

committed. The amount of free-throws to be awarded depends on the type of foul, violation,

or the game situation. The free-throw shot is considered to be one of the most important shots

in the game and sometimes determines the outcome of a game. It is essential that all players,

no matter their position or size, are successful from the free-throw line. The shot should be

one of the easiest to make since the player is unopposed and has ample time to attempt the

shot. A successful free-throw shot requires good concentration, relaxation, but most

importantly good body mechanics in the shot itself.

In order to achieve success when attempting a free-throw, a player should accomplish

the following phases: Phase 1, “the approach and stance phase”, the player will approach and

align themselves at the free-throw line with feet shoulder width apart in a square stance or a

slightly staggered stance. The most common stance is the slightly staggered stance, in which

the front foot is at the free-throw line and the toe of the back foot is even with the arch of the

front foot (Ball, 1989). Phase 2, “the shot set and backswing phase”, in this second phase, the

player has a proper amount of forward trunk lean, hip and knee flexion, while the ankles are


dorsiflexed. The basketball in this phase should be held closer to the trunk aligned above the

shooting knee. The shoulder, hip, knee, and ankle of the shooting side are lined up vertically as

the player prepares for the backswing phase (Hudson, 1982). Phase 3, “the force producing

phase”, the player is producing force through the movements of their body parts. Projecting

the ball to the basket by using upward and forward force is produced by extending the player’s

legs and trunk, as well as straightening their shooting arm. During the force producing phase

the basketball should be held in front of the body with the shooting hand directly behind the

ball, and the non-shooting hand to the side of the ball for balance. The fingers are spread

comfortably while the basketball sits on the base and pads of the fingers. The force producing

movements for the shot begins when the trunk reaches the vertical position and the ball is held

just above shoulder level. By the end of this phase, the player’s knees are in maximal flexion

and the vertical velocity of the ball is zero (Hartley & Fulton, 1971). Phase 4, is the “critical

instant of the ball release.” The shooter has no determining affect once the ball is released and

in flight. At the critical instant of the ball being released, the player’s trunk and legs should be

fully extended, indicating that the hip, knee and ankle joints have made a full contribution to

the flight of the ball. The trunk should be vertical and not leaning forward or backward during

the release and follow-through phase of the shot (Penrose & Blanksby, 1976). The player’s

shooting shoulder should be flexed in a position in which it is almost pointing vertically at the

ceiling. The player’s elbow should be almost at full extension by the time the ball is released to

ensure that this joint has made a full contribution to the flight of the ball. It has been reported

that “a full range of elbow movement is related to greater success in the free-throw of club

level basketball players (Stankovic, Simonovic, & Herodek, 2006).” The wrist should be at a


position halfway between full flexion and full extension to ensure that the shooting hand is

moving at maximum velocity as the ball is being released. If the ball is released too early or too

late, the velocity of the ball will not be optimum as the wrist and elbow joints will be speeding

up or slowing down rather than being at peak velocity. Wrist flexion provides the final stage for

releasing the ball and will determine both the velocity and angle of projection of the ball (Hess,

1980). Phase 5, “the arch of the shot” is indicated after the ball leaves the shooter’s hand. The

ball becomes a projectile that has a parabolic pathway to the basket. The ball will reach the

basket with either at a high arch or a low arch. The higher the arch, the greater the chance for

the ball to go into the basket. The amount of arc on a shot is related to the strength of the

player. A higher arched shot requires more strength to generate the heightened vertical

velocity required to attain a greater peaked height. The angle of the release should be between

50-55 degrees (Brancazio, 1981). A higher vertical velocity would require a larger range of

motion from the legs and the shooting arm. Phase 6, and the final phase of the shot is the

“follow-through phase”, in which all the joints continue to move through to the end of their full

range of motion following the release of the ball. In the follow-through phase, the legs are fully

extended and the ankles are plantarflexed. The trunk is vertical and the hip on the same side as

the shooting is aligned vertically with the knee and ankle, as well as with the joints on the

shooting arm.

Many advanced players at highly competitive levels, whether on an individual basis or a

team level basis, are unsuccessful making free-throw shots. Most statisticians believe that the

free-throw shot accounts for 20% of every game, and in many cases may determine the

outcome of a game or even a season. In the 2012-2013 NBA basketball season, the Oklahoma


City Thunder shot a league high of 82.8% from the free throw line while the Los Angeles Lakers

shot a league low of 69.2%. The Lakers never survived the first round of the playoffs, being

swept by the San Antonio Spurs while shooting a miserably low 60.8% from the free-throw line.

The Spurs had a free-throw percentage of 80.5% in the triumph, accrediting the series success

to their free-throws made. The NBA league average for teams successfully making their free-

throw shots was at 75.3%. Which means, most teams missed an average of 24.7% of their free-

throw shots. In the NCAA Division I Men’s 2012-2013 season, every school missed at least

20.5% of their free-throw shots. On the NCAA Division I Women’s side, the percentage was

slightly better at a 19.5% of missed shots. High School Boy’s missed at least 22% of their free-

throws in the 2012-2013 season. Orem High School in Orem, Utah was the country’s lowest

free-throw percentage team at 49%, which means the team missed more than half of all of the

team’s free-throws attempted. So the main question is, why? If the shot is unopposed, and the

shooter has ample time to attempt the shot, why are so many players missing? Players

between the ages of 14-40, male or female, professional or high school equivalent are

struggling yearly with the sports “free” shot.

HYPOTHESIS:

After an individual analysis, it is hypothesized that the trajectory of the ball can be

improved by increasing the maximum height of the ball’s flight through appropriate

adjustments at various lower limb joints. This written analysis will explain the mechanics of an

individual’s basketball free-throw shot, analyze, and make adjustments to improve the player’s

shot using a coach’s intervention through this research.


DETERMINISTIC MODEL: Figure 1. (Making the Free-Throw Shot).

Figure 1. This Deterministic Model explains the hierarchy of making the free-throw shot and primarily focuses on vertical force which highlights the hip, knee and ankle joint angles, which is the key focus for this study that will support the hypothesis. (Please note that vertical velocity is equal to horizontal velocity; vertical acceleration is equal to horizontal acceleration; vertical force is equal to horizontal force).

MAKE THE FREE-THROW SHOT

Vertical Position

Vertical Distance (small change)

Time V Velocity

V Acceleration

Time V Force

Hip Angles Knee Angles Ankle Angles

Horizontal Position

Horizontal Distance (fixed)

H Velocity Time

H Acceleration

H Force

Shoulder Angles Elbow Angles Wrist Angles

Time


METHODS

In order to start this analysis, the participant in this research will be referred to as

“Athlete-X”. Athlete-X is a male that is 25 years of age. Athlete-X is a first year coach for a

middle school boys’ basketball team. Athlete-X had 3 years of basketball experience while

playing in high school, and currently plays recreationally in a men’s league. Athlete-X will

perform free-throws using the one-hand push shot approach in an indoor gymnasium. Athlete-

X is a left handed shooter. The fact that the participant is left handed is irrelevant to this

particular study. The distance from the free throw line to the glass backboard is at a regulation

length of 15 feet. The basket is suspended from the ceiling. The rim of the basket is at a

regulation height of 10 feet. He will be using a Wilson Evolution men’s indoor basketball,

standard size of 29.5 inches in circumference.

A Sony DCR-DVD610 Handycam Camcorder with 40x optical zoom/2000x digital zoom

and 680K pixels will be used. The video camera will be sitting on a universal tripod standing at

approximately 18 feet perpendicular from where Athlete-X is attempting his free-throws, near

the left sideline of the basket. After recording Athlete-X’s movement to video, the video will be

uploaded to a motion analysis system software called Kinovea. Multiple trials of the data will

be collected in Kinovea in order to measure critical time points in the kinematic movements

being measured.

There are two basic free-throw styles that can be used in the game of basketball. The

one-hand push shot or overhand push shot and the unorthodox and unusual underhanded

shot. The underhanded shot is not commonly used at any level of play. This technique is not


commonly used because there is no carry-over to gameplay other than the free-throw

attempts. Meanwhile, the one-hand push shot is used for many other types of shots during

gameplay. This research study will focus on the one-hand push style of the free-throw as this is

the commonly used technique for most players during gameplay.

Athlete-X will perform 25 free-throw attempts as the pre-administration of this research

analysis. The number of free-throws made will be recorded and converted to a free-throw

percentage. After 25 free throws, Athlete-X will participate in a coach’s intervention, where a

feedback review and video motion analysis along with techniques to improve his free throw

shot will be provided. After 3 days, of practicing the techniques provided, Athlete-X will be

reevaluated as he attempts 25 free-throws as the post-administration analysis to this research.

This study will either confirm or disprove the hypothesis statement. This analysis can improve

Athlete-X’s free-throw percentage in his men’s league along with help teach to improve this

skill to his middle school basketball players.

On day one, Athlete-X was asked to perform 25 free-throws as a pre-administered

evaluation of this skill on task. As the skill is being performed, the video of the player’s

performance is simultaneously being recorded. Written notes of the player’s biomechanical

performance will be cross-referenced with the video analysis recording afterwards. The

number of free-throws successfully made out of Athlete-X’s 25 attempts will determine results.

While performing his pre-administered 25 shots, it was observed that Athlete-X was not

bending sufficiently in his lower limbs, especially at the knee joints. The lack of flexion was

causing the flight of the basketball to travel in a straight line. Flexion describes a bending

movement that decreases the angle between two parts of the body. In order for the ball to go


into a vertically round cylinder at a height of 10 feet and from 15 feet away, the ball needs to

travel in an arched trajectory to be a successful shot. What is being described is the projectile

motion. This is the motion of an object being projected at an angle into the air. The factors

that can influence an objects trajectory include gravity and air resistance. A projection can

move at any angle between 0 degrees (horizontal) or 90 degrees (vertical). Trajectory is

influenced by the projection speed, the projection angle and the relative height of projection

(Blazevich, 2010, p. 25).

The projection speed is determined by the distance which a projectile covers, the faster

the speed the further the object will go. In the case of attempting a free-throw, the basketball

moves vertically, therefore the projection speed will determine the height it reaches before

gravity accelerates it back to earth. The projectile angle affects the range of a projectile. When

an object is projected at angles between 0 degrees and 90 degrees, the object will travel

vertically and horizontally. When the angle is greater the object attains greater vertical height

but less range.

Relative height of projection is the vertical distance between the projection point of an

object and the point in which it lands. This greater angle is good for a free-throw attempt. The

optimum angle for a free-throw is approximately 51 degrees (Gordon, Christopher, Hamilton, &

Reinschmidt, 1997). The free-throw shot needs a greater angle of projection to improve the

accuracy of the shot. The basketball is more likely to be made if it falls vertically then if it were

to hit across the top cylinder of the basket.


All three of Newton’s Laws and the Law of Gravity work together to allow the player to

come up onto their toes to shoot the free-throw shot. Athlete-X needs to overcome inertia by

having an applied forces against them. In order to do this, he must apply a large and well

directed force against the earth which applies an equal and opposite reaction force against him,

which also allows the shooter to come up onto their toes. Because of Newton’s law of

gravitation it is necessary to produce large vertical forces, or have a low body mass in order to

jump higher (Blazevich, 2010, p. 44-46).

Because Athlete-X was not bending at the hips, knees and ankles properly, the

trajectory of the basketball had a line drive affect rather than the arc affect. It was also noticed

that Athlete-X was not extending properly after the release of his shot, something that should

go together with adequate flexion. Extension describes a straightening movement that

increases the angle between two parts of the body. Athlete-X’s shoulder, elbow and wrist

flexion and extension appeared to be satisfactory. The amount of wrist flexion seemed visually

adequate by observing the amount of velocity on the ball at release. Athlete-X was successful

making 11 out of 25 free-throws attempted for a 44% free throw percentage.

After careful review of written notes and cross referencing them with the video analysis

on the Kinovea software, it was determined that Athlete-X was definitely not bending or flexing

adequately, which was not allowing him to successfully make half of his free-throw attempts

(44%). This was determined on the Kinovea software by slowing the framework down from

Athlete-X’s approach to the basket, starting at his backswing through his body’s entire

movement of the free-throw attempt, until the release of the basketball. This is called


momentum of force. Momentum is simply defined when force is needed to get an object to

exert velocity in order to overcome inertia. In order to change an objects momentum, force is

needed to be applied. To accelerate vertically, larger vertical impulses is needed, this will

propel him into the air. Impulse is a production of force and time, therefore the greater the

impulse the greater the change in momentum (Blazevich, 2010). This biomechanical principle is

present in a free-throw shot when a player is bending their legs applying force as a vertical

impulse into the ground in order to propel themselves up onto their toes at release.

The Kinovea software was also able to track the path of the ball or its trajectory. A

trajectory of a projectile is the path that a thrown object will take under the laws of gravity,

neglecting all other forces without propulsion. Athlete-X will have to apply more force in the

backswing phase of his free-throw by applying more flexion and full extension at the hip, knee

and ankle joints in order to successfully improve the trajectory of the shot.

Athlete-X was given a coach’s intervention, where findings were thoroughly discussed.

It was suggested and recommended that Athlete-X do proper stretches of the lower extremities

primarily the quadriceps, hamstrings and calf muscles before and after his practice trials and

the post-administered trial. The footage of his free-throws was reviewed allowing him to

identify his improper flexion and extension of his lower extremities. It was recommended that

he place a 2 foot stool next to him while shooting during his practice trials. It was told to

Athlete-X to visualize sitting down on the stool in order to create adequate flexion and then

coming up off of his toes at the release. Athlete-X should practice this tool 25 times on practice

day one and two, before his post-trial is re-administered.


RESULTS

Figure 2. (Pre-assessed Flexion at the backswing phase).

Figure 2. At the backswing phase of Athlete-X’s pre-assessed free-throw trial, the player applied minimal momentum of force into the ground by not flexing enough at the hip, knee and ankle joints. As seen here in Figure 2, Athlete-X bent at a 143° angle in the flexion stage of the backswing phase.


Figure 3. (Pre-assessed Extension at Critical Instant of ball release phase).

Figure 3. At the critical instant of the basketball being released, Athlete-X was at extension of the hip, knee and ankle joints at an angle of 169°, a difference of 26° from the backswing phase to the release phase of the pre-assessed free-throw trial.


Figure 4. (Trajectory angle at the release of the pre-assessed free-throw).

Figure 4. This picture shows the trajectory angle of 41° that the basketball was being projected during the release phase of the pre-assessment trial of the free-throw shot. The shot appeared to be projected in a straight line rather than an arc. The ball should launch at a preferable angle between 50°-55° at point of release.


Figure 5. (Post assessed Flexion at the backswing phase).

Figure 5. At the backswing phase of Athlete-X’s post assessment trial, the player increases flexion at the hip, knee and ankle joints allowing a greater momentum of force to be applied into the ground. Athlete-X bent at an angle of 89° in the flexion stage of the post assessed backswing phase.


Figure 6. (Post assessed Full Extension at Critical Instant of ball release).

Figure 6. At the critical instant of the basketball being released, Athlete-X was at full extension at the hip, knee, and ankle joints at an angle of 175°, a difference of 86° between the backswing phase and the release phase of this post assessed free-throw trial.


Figure 7. (Trajectory angle at the release of the post assessed free-throw trial).

Figure 7. This picture shows the trajectory angle of 52° that the basketball was being projected during the release phase of the post assessment trial of the free-throw shot. The shot appeared to be projected in a proper arc. The ball should launch at a preferable angle between 50°-55° at point of release. Athlete-X was near perfect.


Figure 8. (Pie Charts of Pre & Post Assessment for Free-throws Made).

11

14

Pre Trial

Free-throws Made Free-throws Missed

18

7

Post Trial

Free-throws Made Free-throws Missed

Figure 8. The two pie charts are labeled “Pre” and “Post Trials”. The blue portion of the chart shows the amount of free-throws made out of 25 attempts. The gold portion shows the amount of free-throws missed out of 25 attempts. Pre Trial shows 11 out of 25 free-throws made for a shot percentage of 44%. The Post Trial shows a 28% improvement in free-throw percentage, where 18 of 25 shots were made for 72%.


FINDINGS & COMPARISON

To summarize this study, Athlete-X was asked to perform the sports uncontested shot in

the basketball free-throw. As a pre-trial, Athlete-X shot 25 free-throws missing 14 and only

making 11 in successfully for a free throw percentage of 44% as seen in Figure 8 of this written

technical report. While attempting the free-throws, Athlete-X was noticed not bending

sufficiently at the hip, knee, and ankle joints. The lack of flexion at the lower extremity joints

did not allow adequate momentum of force to be applied into the ground during the backswing

phase of the trial. This was confirmed when the video footage was uploaded to the Kinovea

software and the critical time point was saved as an image seen in Figure 2 in the Results

section of this report. Figure 2 shows Athlete-X slightly bending at a 143° angle.

Even though Athlete-X was extended at the critical instant of the ball being released, the

trajectory of the ball projected at an angle of 41° rather than an arc of a preferable angle of 52°.

The flight of the ball appeared to take a path in a “straight” line as seen in Figure 4.

The inadequate flexion at the backswing phase did not allow Athlete-X to fully extend

which was the main reason why his shot flew in a “straight” path rather than an arc. Athlete-

X’s hip, knee, and ankle joints were at an extension angle of 169° a difference of 26° from

flexion at the backswing phase to the critical instant of the ball being released at extension as

seen in Figure 3 of this report.

Consultation and feedback was given to Athlete-X, and after three days of practice and

adequate stretching of the lower extremities a post-trial was administered. Significant results

were established between the pre and post trials. Before attempting his free-throws, it was

noticed that Athlete-X focused on stretching his lower extremities slightly more than the rest of


his body. When asked to take 25 free-throws as the post administered trial, Athlete-X

successfully made 18 of his 25 shots for a free-throw percentage of 72%, an improvement of

28% from pre to post trials as explained in Figure 8 of the Results section.

It was clearly noticed that Athlete-X was bending more during the backswing phase of

the post-trial compared to his pre-trial. Increased flexion at the backswing phase was video

recorded and uploaded to Kinovea and the critical point was established and saved as an image

as seen in Figure 5. The Figure shows adequate flexion at the hip, knee, and ankle joints which

were at an angle of 89° an increase of 54° between the pre and post trials.

Because adequate flexion was applied, Athlete-X was able to fully extend at the ball

release phase. Momentum of force into the ground was established when Athlete-X was

adequately flexing and full extension was established which is evident when looking at Figure 7.

This figure shows the trajectory flight of the ball had a near perfect arched angle of 52° when

the ball was released.

Figure 6, shows Athlete-X at full extension at an angle of 175° at the critical instant

when the ball was being released, an improvement of 6° between pre and post trials. The

difference of 86° from flexion at the backswing phase to the critical instant of the ball being

released at extension as seen in the Results section in this report.


CONCLUSION

As a result to this study, it can be concluded through extensive research, video

integration, motion analysis, and coaching experience that the support of the hypothesis can be

confirmed. The trajectory of the ball can be improved by making appropriate adjustments at

various lower limb joints. When a player is not flexing properly at the backswing phase of the

free-throw, momentum of force is not being applied into the ground not allowing the player to

fully extend when releasing the ball. This will make the flight of the ball travel in a “straight”

path rather than an arched one.

When asked to perform 25 free-throws during the post trials, Athlete-X improved his

free-throw percentage significantly by 28%. By increasing flexion at the backswing phase

enabled Athlete-X to release the ball at full extension allowing the trajectory to be projected to

a near perfect arch of 52°.

It is advised to Athlete-X and his coach to examine any skill carefully, such as the

basketball free-throw, before proceeding to make any type of adjustments. In the case of this

study, Athlete-X was given an appropriate coach’s intervention and applied lower limb

stretching and different shooting techniques to his practice routine. The stretches focused on

the areas of the quadriceps, hamstrings, and calf muscles in the lower limbs, done before and

after the practice trials. A 2 foot stool was set alongside Athlete-X while shooting his free-

throws. The player is to visualize sitting on the stool as a reminder to bend while shooting.

These simple tools were given to Athlete-X to practice and the results were evident when

transferred over to the post trials. This research clearly supports the hypothesis of this study.


References

Ball, R. (1989). The basketball jump shot: a kinesiological analysis with recommendations for

strength and conditioning programs. National Strength and Conditioning Association

Journal, 11(5), 4-12.

Blazevich, A. (2010). Sports Biomechanics, the Basics: Optimizing Human Performance. .

Brancazio, P. J. (1981). Physics of basketball. American Journal of Physics, 49(4), 356-365.

Gordon, R., Christopher, Hamilton, & Reinschmidt (1997). Optimal Trajectory of the Basketball

free throw. Journal of Sports Sciences, 15(5), 491-504.

Hartley, J. W., & Fulton, C. (1971). Mechanical analysis of the jump shot. Athletic Journal, 51(7),

92, 95, 128-129.

Hess, C. (1980). Analysis of the jump shot. Athletic Journal, 61(3), 30-32, 37-38, 58.

Hudson, J. L. (1982). A biomechanical analysis by skill level of free throw shooting in basketball.

Paper presented at the International Symposium of Biomechanics in Sports, Del Mar,

CA.

Mood, D., Masker, F., & Rink, J. (1991). Sports and recreational activities for men and women

(10th ed.). St. Louis: Times Mirror.

Penrose, T., & Blanksby, B. (1976). Film analysis: two methods of basketball jump shooting

techniques by two groups of different ability levels. Australian Journal for Health,

Physical Education and Recreation, 68(March), 14-23.

Stankovic, R., Simonovic, C., & Herodek, K. (2006). Biomechanical analysis of free throw

shooting technique in basketball in relation to precision and position of the players.


Paper presented at the XXIV International Symposium on Biomechanics in Sports,

Salzburg, Austria.

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Basketball Free Throw: A Written Technical Reportknixfan.com/files/Awrittentechnicalreport.docx · Web viewBASKETBALL FREE THROW: A WRITTEN TECHNICAL REPORT23 Running head: BASKETBALL