A curl-up on a stable surface, rectus abdominis muscle activity was 21% of MVC and external oblique muscle activity was 5% of MVC.
core
The diaphragm
The muscle that is primarily targeted and developed when doing sit-ups and tightening the abdominal wall is the rectus abdominis. This muscle is commonly referred to as the "abs" and is responsible for flexing the lumbar spine.
This is muscle flexion or isotonic contraction.
The thoracic cavity is the upper part of the torso and contains organs like the lungs and heart, while the abdominal cavity is the lower part. These two parts are separated by the diaphragm.
Hamstring - Semimembraneous
The main muscle used in curls is the biceps.
Abdominal muscles
The abdominal curl machine can help strengthen the core muscles, improve posture, and reduce the risk of back pain.
The thoracic cavity is separated from the abdominal cavity by the diaphragm. This is a broad flat muscle. (muscular) diaphragmThe diaphragm is a muscle that separate the thoracic from the abdominal cavity. The pelvis is the lowest part of the abdominal cavity and it has no physical separation from it Diaphragm
The preacher curl exercise primarily targets the biceps muscle group.
Incorporating abdominal curl ups into your workout routine can help strengthen your core muscles, improve posture, and reduce the risk of lower back pain.
Vastus latrealis
the abdominal is your abs which is a muscle and your pelvis is a bone
The abdominal region has little bony protection, and is susceptible to external injury.
Curl-ups are abdominal exercises performed to strengthen the called the rectus abdominis muscle. This exercise also helps to tone your midsection. To perform a curl-up, you lie on your back with knees bent and the feet flat on the floor. Place your hands behind the head and tuck the chin to the chest. Curl the head, shoulders, and upper back off the floor. Roll back down to your starting position and repeat the movement.
The rectus abdominus muscle, which is the muscle that becomes a six-pack if you train it, is the muscle at the front of the abdominal wall and stretches across the specified region.