Understanding the abdominal muscles and their relationship to movements of the spine. 1) Rectus abdominus — flexion, lateral flexion. 2) External oblique — flexion, lateral flexion, rotation forward, forced exhalation. 3) Internal oblique — flexion, lateral flexion, rotation forward, forced exhalation. 4) Transversus abdominis — forced exhalation, holding in viscera.
To fully develop each of these muscles it is necessary that they be involved in all their actions in specific exercises.
II. Examination of some of the more common abdominal exercises.
1) Sit-up vs. the crunch. 2) Reverse sit-up (crunch). 3) Double crunch. 4) Reverse trunk twist vs. twisting sit-ups (crunches). 5) Side bend (all variants). 6) Seated knee-ups. 7) Shoulder rotation with rubber tubing, cable or machine. 8) Forced expiration with The Breather?. 9) Russian twist. 10) Yessis machine sit-ups (2 variants). 11) Straight leg raises, lying and hanging. 12) Machine crunches. III. How to select “the best”. 1) Purpose. 2) Muscle targets. 3) Selecting the exercise.