An increase in body temperature increases range of motion. Warming up the body through physical activity increases range of motion while lowering body temperature decreases range of motion.
The amount of length achieved from a stretch is increased when tissue temperature is elevated. Superficial heat, deep heat and active warm up are three ways to warm the body and affect range of motion.
Superficial heat includes paraffin, Fluidotherapy, infrared radiation and heat packs. The easiest and most cost effective form of superficial heat is heat packs. Flexibility has been shown to improve when superficial heat is applied with a simultaneous low load static stretch.
Applying deep heat to connective tissue can be achieved by ultrasound. An elevation in tissue temperature greater than 37 to 39 degrees Fahrenheit obtains an increase in the viscoelastic properties of collagen. Continuous ultrasound for seven to eight minutes was found to increase tissue temperature and result in viscoelastic changes of collagen.
Warming the body by performing physical activity raises blood, muscle, tendon and ligament temperature. Performing a warm up reduces the risk of injury by preparing the body's movable joint structures to move freely. Performing isometric exercises before stretching enables muscles to withstand more elongation.