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 REPORT1
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 makerecommendations 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 indicatedafter 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 averagefor 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).
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 lengthof 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, wherea 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 reevaluatedas 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 verticallyround 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 angleaffects 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 projectionis 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.