While performing the exercise, keep your fingers loose behind your head and do not pull your head forward with your hands. Additionally, the positioning of your body on the physioball should remain constant during the entire exercise. If your hips roll back, your shoulders will rise and you will lose the isolation of the abdominal muscles. An easy way to prevent this from happening is to focus on keeping the thighs parallel to the ground.
VARIATION
Physioball Crunch With Trunk Rotation
Incorporation of the twisting motion diverts the focus of this exercise from the rectus abdominis to the internal and external obliques. This exercise is useful in linking the movement of the arms to the movement of the legs in freestyle and backstroke.
Cable Crunch
Execution
1. Kneel on the ground in front of a pulley machine. With your elbows bent, hold the separate ends of a rope pulley handle behind your head.
2. Holding your hips stationary, bend at the waist and crunch your torso downward.
3. Slowly return to the starting position.
Muscles Involved
Primary:Rectus abdominis
Secondary:Serratus anterior, internal oblique, external oblique, transversus abdominis
Swimming Focus
Use of the pulley machine allows this exercise to be performed with variable resistance. As a result, the focus of the exercise can be shifted from endurance to strength simply by altering the weight and number of repetitions performed. The variable resistance offers an advantage when compared with most of the exercises in this chapter, which depend primarily on body weight. The motion performed during the exercise closely mimics the motion performed during a flip turn, but because of the wide range of motion through which the abdominal muscles are targeted and the variable resistance, this exercise is beneficial across all four strokes.
To gain maximal benefit when performing the exercise, emphasize a curling motion, beginning with the upper torso and continuing all the way down to the waistline. When performing the exercise, resist the temptation to pull downward with the hands. Doing this shifts the focus away from the abdominal muscles and places unnecessary stress on the joints and muscles of the neck.
Seated Physioball Abdominal Hold
Execution
1. In an upright seated position on a physioball, set your abdominal muscles.
2. Slowly lean backward until your upper torso is at a 45-degree angle to the floor.
3. Lift one arm forward until it is in a streamlined position.
4. Lower and then repeat with the opposite arm.
Muscles Involved
Primary:Rectus abdominis, rectus femoris, iliopsoas
Secondary:Serratus anterior, internal oblique, external oblique, transversus abdominis
Swimming Focus
It is easy to visualize how this exercise can contribute directly to strengthening the core stabilizers as they are used while swimming backstroke. The addition of trunk rotational movements similar to those performed while swimming backstroke emphasizes the internal and external obliques. By moving both arms in unison and holding a streamlined position, the focus of the exercise shifts to strengthening the core muscles as they contribute to maintaining a streamline during both starts and turns.
While performing this exercise, the main focus must be placed on (1) maintaining the set abdominal position during the entire exercise and (2) performing the arm and trunk movements in a slow, controlled manner.
Russian Twist
Execution
1. From a seated bent-knee position, tighten your abdominal muscles, lean backward, and lift your feet 4 to 6 inches (10 to 15 cm) off the ground. Hold a medicine ball in your hands at your chest.
2. Moving only with your trunk, rotate to one side. Quickly reverse the movement and rotate to the opposite side.
3. Continue until you have completed the set number of repetitions.
Muscles Involved
Primary:Rectus abdominis, external oblique, internal oblique
Secondary:Psoas major
Swimming Focus
The main focus of this exercise is the internal and external obliques, which are extremely important in linking the movements of the arms and legs during freestyle and backstroke, especially when you are in an elongated position. The upper-trunk rotational movements are similar to those performed during open turns for both butterfly and breaststroke, so this exercise can also be used to improve the speed at which you can complete a turn and get off the wall.
To keep the focus of the exercise on the abdominal musculature, hold the medicine ball close to the chest. If you hold the ball away from your chest and emphasize touching it to the ground, you may compensate by using the shoulder muscles instead of the abdominal muscles.