Do you know how to quickly relieve a cramp? Use the opposite muscle! Muscles are connected to bones and when they contract, they move the bones (motion). Muscles also work in pairs, so if one muscle contracts, the other muscle lengthens. For example, when you contract your bicep muscle, the tricep muscle will lengthen. Both muscles can not contract simultaneously so, in the case of a cramp, if you force contraction of the non-spasmed muscle, the cramp will subside. Pretty cool. Huh?!