One of the most important, yet overlooked, aspects of any exercise or training program is the recovery phase, or time spent resting. It is all too common a thought that rest time is a period of doing no work, and while you are not actually doing any physical work, physiologically your body is seizing the opportunity to repair itself to become stronger in preparation for the next exercise stress placed upon it. It is during rest that the body becomes stronger.
Muscle Breakdown During Exercise
While you exercise, your muscles work to meet the demands you place on them. During that work, muscles deplete their stores of energy (muscle glycogen) and start to become fatigued. The glycogen is what fuels the muscle contractions that cause muscle movement, and it is from these contractions that muscles experience small tears.
The Recovery Process
Recovery begins once you are done exercising. Muscle glycogen stores get replenished, and the body begins the process of rebuilding and repairing those tiny muscle tears. Time is necessary for this repair process as the body rebuilds the muscle stronger than it previously was. This is how strength training, or any type of exercise training, works. Muscle gets broken down to rebuild and become stronger, and more resistant to that level of exercise stress, so that it can withstand more the next time. Rest is essential to implement these improvements.
Rest and Cardiovascular Training
When it comes to cardiovascular exercise, rest is between sets of higher intensity work and between workout sessions. In the case of a single exercise session, rest is specific to the goal of the workout. If the workout is endurance training, rest time will be less; if it is a speed session, rest time will be greater. Rest time varies so that you can perform the work at the desired level. More rest is allotted between speed sets because it takes a greater amount of work to move fast than it does to move slower.
Rest and Strength Training
Rest during strength training exercise is most commonly overlooked, as many people skip the down time between sets. The principles of rest for strength training are similar to those of cardiovascular training. Higher intensity efforts require more rest between sets than lower intensity, and the rest is specific to the goals of the workout. If you are trying to gain strength and power, more rest will develop greater gains. In a study reported in the November 1995 issue of "The Journal of Strength and Conditioning Research," it was observed that a rest time of three minutes between sets elicited greater strength gains than did a 30-second rest time in the back squat exercise.
Post-exercise rest is essential. Without proper rest, you will begin to experience performance decrements. You will feel more tired than usual and exercise will become more difficult because you are not recovering and are not prepared enough to handle the stress of another workout.