what muscle is the prime mover when doing a push up
If you were to look at the image to the left these are ALL the muscles of the hip flexorsâ¦ if you notice that the abdominal wall is NOT one of them. These are the PRIME movers in decline sit-ups and most other sit up variations. So doing countless reps and decline angles only further continues to improve the functionality and muscular development of the hip flexors, not develop the abdominal wall.