When one muscle in a pair contracts the other expands.
the other muscles relax
antagonistic muscle action.
the answer is when one muscle contracts the other relaxes
relax
One group of muscles contracts, and the other group extends. As an arm moves down, the bicep muscle (the one that faces the front side of the body and goes from the shoulder to the elbow) relaxes. When the muscle relaxes, it goes from being contracted to elongated. This relaxation happens at the same time that the tricep muscle (the one that faces the backside of the body and goes from the shoulder to the elbow) contracts. This happens because the human body's skeletal muscles have what can be considered compliments. I say this to mean that when a muscle relaxes, there is a muscle that contracts simultaneously. Therefore, they move antagonistically to each other. This is to serve the purpose of creating specific movements that help assist in locomotion. On the molecular level of what happens when a muscle contracts and relaxes, the actin and myosin filaments in muscle fiber overlap to contract and separate to relax.
Relaxes
It Contracts
relax
It relaxes
contracts - for antagonistic muscle pairs e.g. muscles in arm (when one relaxes, other contracts, and vice versa)
When one muscle in a pair contracts the other expands.
Yes. An antagonistic pair of muscles, such as the biceps and the triceps, allows movement of body parts through opposing motions. As one of these muscles contracts, the other relaxes.
Relax