Warm-up

Warming up is performed before a performance or practice. Athletes, singers, actors and others warm up before stressing their muscles. It prepares the muscles for vigorous actions.

A warm up generally consists of a gradual increase in intensity in physical activity (a "pulse raiser"), joint mobility exercise, and stretching, followed by the activity. Warming up brings the body to a condition at which it safely responds to nerve signals for quick and efficient action.

For example, before running or playing an intensive sport, the athlete might slowly jog to warm their muscles and increase their heart rate. It is important that warm ups be specific to the activity, so that the muscles to be used are activated. The risks and benefits of combining stretching with warming up are dispute, although it is generally believed that warming up prepares the athlete both mentally and physically. In a meta-study of 32 high quality studies, about 4/5 ths of the studies showed improvements in performance.

Warm-up programs can improve the strength of the knee muscle, which, in turn, may decrease injuries.

A comprehensive warm-up program did not significantly decrease injuries in football compared to a control group.

Direct physical effects of warm ups are:

Stretching is part of some warm up routines, although a study in 2013 indicates that it weakens muscles in that situation. There are 3 types of stretches: ballistic stretching, dynamic, and static stretching:

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