A warm up is intended to raise the body temperature and prepare a player physiologically and psychologically to compete in a competitive game. Research has suggested that the optimum duration of the warm up period, before flexibility or functional activities are undertaken, should be between 15 and 20 minutes. This should consist of a gradual increase in intensity until the player is working at 70% of maximal heart rate. A warm up at this intensity has the effect of allowing an increase in the range of movement of the joints and improving aerobic performance. This means the player becomes more flexible and running efficiency improves.
A warm up produces a 2 to 3 degree rise in body temperature that can last for 45 minutes. This increase in temperature leads to beneficial changes in body tissue:
In addition to the physiological effects, the warm up has the effect
of preparing the player psychologically by encouraging them to focus
on the physical activity to follow.