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 sternocleidomastoid muscle is superior to the rectus abdominis muscle. The sternocleidomastoid is located in the neck, while the rectus abdominis is situated in the anterior abdominal wall. Therefore, in terms of anatomical position, the sternocleidomastoid is positioned above the rectus abdominis.
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.
Incorporating abdominal curl ups into your workout routine can help strengthen your core muscles, improve posture, and reduce the risk of lower 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.
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 triceps muscle (and still the biceps muscle, to a certain extent).