The electrical activity of the abdominal muscles was tested during situps to determine the effect upon integrated muscle action potential (MAP). The following types of situps were used in testing 18 college males: (1) trunk curls; (2) AAHPER situp; (3) YMCA situp; (4) modified AAHPER situp; and (5) modified YMCA situp. All situps were performed with the fingers interlocked behind the head and with the knees bent. Findings indicated that altering the YMCA and AAHPER situps so that the feet are not anchored resulted in a significant reduction in MAP's of the abdominal musculature. Also, elimination of the hip flexion portion of the trunk curl situp resulted in diminished electrical activity of the external oblique muscles. (JD)