Just the Deltoid, nothing else
It does has three heads though - anterior, middle, and posterior
They also think that it has 7 different activation regions, but I think that one's still up for debate
gastrocnemius and soleus muscles muscles are collectively referred to as triceps surae
The chest and TRiceps
triceps
The triceps are extensor muscles.
Triceps brachii
The biceps and triceps muscles are examples of skeletal or striated muscle.
The triceps muscles extend (straighten) the arm, while the biceps muscles flex (bend) it at the elbow joint.
The triceps be retact and contract
The biceps and triceps are muscles. They flex and extend the forearm, respectively, so they are considered antagonists.
During a reverse push-up, the muscles primarily worked are the triceps, shoulders, and chest.
The muscles that are in your arms
The muscles used are the pectorials and triceps. This is because the triceps are the muscles used for pushing and the pectorials are near your sholder.