stomach muscles are mostly machine-less.(not required) You work the abb's by doing sit-ups, crunches, push-ups(a little),Running, drop downs(When you hold onto 2 bars and drop down with your legs behind you and push back up, repeat over and over). A machine that would help, would be one that you hold the handle to your right and left, and sitting down. You would pull that handle(attached to a rope or wire) while turning only ur upper body in the opposite direction, left handle you'd turn right and pull(keeping the handle close to center of chest.)
Any exercise that involves lifting the legs, bending the torso, or balancing the body will work the abdominal muscles.
Stomach muscles
If you are discussing "abdominal' muscles as the stomach muscles, YES! The abdominal [stomach] muscles work in tandem with the rest of the trunk muscles in bending, twisting, etc... If you are discussing the muscles of the stomach, per se, I am aware of no connection betwee. Want to lessen your back pain? Join a local gym and work on those muscles!! There are many outlines on the 'net that can tell you what exercises you need to do...
Weight benches work all types of muscles. The muscles that weight benches work are the thighs, biceps, triceps, stomach, legs, chest, back and the glutes.
In cheerleading, you always (most of the time) work on conditioning. Which means you work on arms, shoulders, back, stomach muscles, and leg muscles.
You use your calves, thighs, and muscles in your core and stomach. Sometimes, you work your biceps and shoulders.
I primarily works out your core (stomach) muscles.
Voluntary
these muscles can move in your stomach in not a referable question pleese comment
You cannot control the muscles in your heart and brain, and also your lungs, because they work automatically.
It travels down our esophagus, which is basically a long wide tube that has muscles the whole way down it for pushing food towards our stomach. When we vomit, these muscles work in reverse to push stomach contents back upward.
At both ends of your esophagus there is a ring of muscle. Usually, the muscles keep your stomach's contents where they belong. With laryngopharyngeal reflux, the muscles don't work right and stomach acids backs up into your throat.
The digestive system uses muscles to digest food. For example, stomach muscles help to break down food.