Release to follow through is the main part of the physical game in which the bowler imparts energy from the body to the ball. The more efficient this transfer of energy, the faster ball speeds and higher rotational velocity (RPMs) will be achieved.
Fundamental Rule of The Game
The objective of the physical game is to maximize energy transfer by attaining a body position and swing direction that enables the bowler to move through the center of the ball, maximizing the time and distance the fingers travel down the intended target line.
Wrist flexion to wrist extension
The wrist should move from flexion (cupped) to extension (uncupped) when the fingers leave the holes. This is similar to shaking and rolling dice. In the downswing, the bowler’s hand should naturally move under the bowling ball using wrist flexion. Wrist flexion’s main purpose is to increase the arc distance the fingers can travel under and around the ball until the fingers leave it after the thumb has exited the thumbhole.
Wrist flexion requires use of the wrist flexor muscles in the forearm and wrist. These include C8 root motor groups, flexor carpi radialis, palmaris longus, flexor carpi ulnaris, flexor digitorum superficialis and the flexor digitorum profundus. Wrist extension also uses muscles in the forearm and wrist including C7 root motor groups, extensor carpi radialis longus, extensor carpi radialis brevis, and the extensor carpi ulnaris.
So besides bowling practice, you should put some exercises to strengthen these muscle groups to help optimize your wrist movement. This exercises is not only good for your bowling game but also for your daily life.
Wrist extention is naturally caused by the weight of the ball when the thumb exits the hole. So don’t squeeze your thumb during down swing so that it can exit the hole naturally.
Increasing wrist flexion leads to a potential increase of rotational velocity while decreasing wrist flexion (or moving to wrist extension into release) will reduce the rev rate since the finger arc length will vary.
Elbow extension from release-to-follow through
During the downswing, as the ball approaches the hip, elite bowlers begin to flex the elbow naturally. This creates a hand position which moves under the ball, lengthening the arc distance the fingers will travel under and through the bowling ball. Elbow flexion requires the biceps brachii muscle, located at the front of the arm, opposite of the triceps.
As the bowler moves from release-to-follow through, the elbow should extend fully. The fingers should remain in the ball for the longest possible time, maximizing revolutions. The hand will be at least one meter past the foul line to achieve full elbow extension with the hand vertically lower than the elbow. Elbow extension requires the triceps brachii muscle, located on the back of the arm, opposite of the biceps.
Release to follow through angle
To maximize energy transfer and accuracy, a bowler wants to ensure the downswing-to-release-to-follow through travels parallel to the intended target line as long as possible. A hand and forearm that travels on the target line for a considerable distance will lead to improved launch angle repeatability and consistency.
We don’t want lateral movement. The hand and forearm should move directly under the head on the intended target line, matching the launch angle (skid phase). The elbow should follow the forearm which should follow the wrist which should follow the hand.
The entire entity should be down the target line under the head, most likely near the non-ball side eye. This can only occur with an adequate lateral spine tilt angle.
The hand should move from wrist flexion to extension with a vertical downward movement of the ball-side shoulder. The hand and forearm should remain laterally under the head.
Note: Vertically upward motion reduces ball speed, as the ball becomes a projectile.
Lateral spine tilt
To achieve an ideal release position, a bowler needs significant lateral spine tilt. Lateral trunk flexion enables the ball-side shoulder to lower, moving the elbow and hand closer to the body and under the shoulder. Lateral spine tilt creates an elite swing slot, moving the forearm under the eyes of the bowler (ideally the opposite eye of the ball-side). It enables the hand and forearm to be close to the center of the ball.
Without lateral spine tilt, a bowler can’t move the hand to the center of the ball and on the intended target line. In order to do this, you need to drop your bowling shoulder on your stance and keep it the same through out the approach till release at the foul line.
With this location, maximum energy can be transferred with the hand/forearm going through the ball and the fingers traveling an arc line from release start to fingers exiting the holes.
Note: Core muscle is crucial in keeping your balance when dropping your bowling shoulder. You should begin to implement plank exercises into your daily routine.
Supination of the hand
Ideally, we want to enter the release with the index finger forward. With such a position, the arc distance traveled with the fingers increases. This requires the wrist/hand to supinate (rotate clockwise) in order for the palm to face upward.
The non-bowling arm
Contrary to conventional thinking, the NBA has less to do with balance and more to do with adding energy in the downswing. Specifically, the NBAis directly related to ensuring the non-bowling shoulder doesn’t over-rotate past perpendicular with the target line. The ball-side shoulder should not rotate past the non-ball side shoulder which should remain perpendicular to the intended target line.
If the ball-side shoulder moves off-line of the intended target line by rotating the shoulder counter-clockwise, the bowler must reorient the release-to-follow through direction, which leads to diminishing accuracy and inefficient energy transfer.
Ideally, the ball-side shoulder should rotate under the NBA shoulder as much as possible. The NBA should be relaxed so the NBA elbow will bend and move vertically upward which will contribute to helping the forearm remain on-line.
In short, the hand will move into the body and the elbow will move vertically upward, keeping the ball-side shoulder back and enabling it to rotate under the NBA shoulder.
Thumb exit
A proper fit contributes greatly to an efficient release. The thumb must exit uninhibited as a delayed thumb exit reduces energy transfer and lowers the rev rate. Change the top layer of tape every three games. Something as simple as not changing tape can impact your release negatively.
Some likely issues with the release
It is likely some bowlers have problems with the release because the muscles involved in flexion are stronger or more flexible than the muscles involved in extension. Other bowlers are not able to maintain wrist flexion from the downswing into the release due to weak wrist and forearm flexors.
Bowlers who are having difficulty with an elite release movement have weak triceps brachii muscles.
With a weaker triceps, the elite release movement of extending the elbow is difficult to impossible to achieve. When a bowler’s biceps are stronger than the triceps, the individual is significantly more likely to make the release to follow through movement vertical (lifting) rather than horizontal with the lane. This reduces energy transfer from bowler to ball and simultaneously diminishes the time the fingers remain in the ball, reducing rev rate.
In short, if you want to make your release long, by extending the elbow, it is time to invest in training the triceps brachii muscles of your bowling arm.