Abdominal exercise

Abdominal exercises are those that affect the abdominal muscles (colloquially known as the stomach muscles).

Breakdowns

The anterior abdominal wall is made up of 4 muscles-- the rectus abdominus muscle, the internal and external obliques, and the transversus abdominus.

Effectiveness of abdominal exercises

The effectiveness of abdominal exercise is measured using electromyography (EMG) relative to the traditional crunch. The following ranks abdominal exercises from best to worst in terms of activity detected by the EMG measures:

Activity in rectus abdominus exercise mean activity Bicycle crunch 248% Captain's chair 212% Exercise ball 139% Vertical leg crunch 129% Torso track 127% Long arm crunch 119% Reverse crunch 109% Crunch with heel push 107% Ab roller 105% Hover 100% Traditional crunch 100% Exercise tubing pull 92% Ab rocker 21%

Activity in obliques exercise mean activity Captain's chair 310% Bicycle crunch 290% Reverse crunch 240% Hover 230% Vertical leg crunch 216% Exercise ball 147% Torso track 145% Crunch with heel push 126% Long arm crunch 118% Ab roller 101% Traditional crunch 100% Exercise tubing pull 77% Ab rocker 74%

Safety of abdominal exercises

Abdominal exercises also put some degree of compressive force on the lumbar spine, putting unwanted stress on the lower back. A study of twelve exercises concluded that no single exercise covered all abdominal muscles with high intensity and low compression.

High challenge-to-compression ratio Crunch with feet anchored Crunch with feet free Bicycle crunch Hanging straight leg raise	Low compression, lower challenge Crunch with feet anchored Crunch with feet free
High challenge, higher compression Straight-leg sit-up Bent-leg sit-up	Low challenge-to-compression ratio (not recommended!) Supine straight-leg raise Supine bent-leg raise Hanging bent-leg raise Static cross-knee crunch