E. Perform a sit-up wnder the following conditions:
1. Legs fully extended
2. Legs flexed at the knee and hip
Identify the differences in muscle contribution in these two different leg positions.
SIT-UP WITH LEGS FULLY EXTENDED
<br>The person comes into a deeper posture by pulling forward, not with the hands, but internally, using contraction of the hip flexors deep in the pelvis, contraction of the rectus femoris muscles on the front of the thighs, and contraction of the abdominal muscles. These muscles work best when they pull in a straight line. The lower section of the Internal obliques (abdomen) can have a girdle type effect on the lower midsection when worked properly with the rectus abdominus, through a full range of ...