Your triceps, on the back of your arm, are an even larger arm ... but it does mean you can flex the muscle and show off a ...

While having toned biceps is certainly a flex—literally—that’s not the ... Yup, this minor muscle group on the back of the arms is the key to overall fitness. "The triceps are a super ...

Your tricep muscles contract and pull, while your bicep muscles relax, causing your arm to straighten back out. You can find antagonistic pairs in your legs too. Just extend and curl and see which ...