The muscles of this human anatomy allow movement to happen at joints. These muscles are known as Skeletal muscles. To allow activity at a joint muscles works in sets. Types of this can be found in the elbows and legs.
Muscles managing the shoulder
The muscles which control the motion of the elbow, will be the triceps as well as the biceps. The bicep [Contract: A muscle tenses as fibres shorten.] or shortens, pulling the lower supply up, and inducing the shoulder to flex. Today the tricep [Relax: When muscle fibres stop contracting.] or lengthens. To straighten the shoulder it really is then the tricep which contracts or shortens in order to pull the low arm down, and also at this time the bicep relaxes.
Click on the 'play' switch (or alternatively drag the arrow over the straight bar) when you look at the interactive drawing below to start to see the shoulder flex and straighten as a result of the triceps and biceps relaxing and contracting.
Muscles controlling the knee
Whenever we glance at the leg we are able to see the hamstring and the quadricep managing the motion. The hamstring [Contract: A muscle tenses as fibres shorten.], pulling the reduced knee up-and resulting in the knee to bend. At this time, the quadricep [unwind: whenever muscle mass fibres stop getting.] . To straighten the leg, the quadricep agreements, and draws the lower leg down. Currently the hamstring is relaxed.