Probably most of the lower body and back muscles, such as your gluteus maximus and your quadriceps.
300
your muscles are not streched out so they get used to not being used
the muscles starts streching every moment you sit down
Hamstrings,...
The gluteus set of muscles are used only to sit down on, so they could probably be considered the laziest set of muscles in the entire body.
Hamstring
Rectus Abdominis
Rectal Abdominis
It is called a low pulley row machine. It is used to work out the back muscles of your body.
The fixator is one of many muscles used during situps. The fixator muscle stabilizes one part of your body when you move another part.
It is generally not recommended to sit down immediately after running because it can lead to muscle cramps and stiffness. It is better to walk around and do some light stretching to help your muscles cool down gradually.
Mostly your forearm muscles but also your bicep. A good way to work out your forearm is to sit on a bench with a weight in your hand and curl your wrist up and then let it down. Do that twenty times and do four sets of them with each arm.