A critical relationship exists between physiological recovery during the sleep state and an athlete’s ability to train at maximum capacity with optimal results.
Jacobsen et al. 2008 showed that using an individualised sleep system directly impacts on decreasing the shoulder and back pain of the individual, research has shown clear increases in the quality of sleep as a result.
There are many arguments supporting the restorative function of sleep.
The metabolic phase during sleep is anabolic; anabolic hormones such as growth hormones are secreted preferentially during sleep. It is not just that cortisol (stress hormone) concentrations are low during most of a normal night: sleep positively inhibits the secretion of cortisol and appears to do the same for that of catecholamines (stress hormones).
Deep sleep is the normal stimulus for the release of most of our growth hormone, an anabolic hormone that increases the synthesis of protein mobilizes free fatty acids to provide energy, thereby saving amino acids from catabolism (breakdown). Growth hormone acts, for example, directly to enhance with repair of tissues.
Protein synthesis and cell division reach their maximum values during sleep and are minimum during wakefulness. When tissues have been damaged, the rate of healing is greater during sleep, whatever the time of the injury. Adrenalin, released through wakeful stress prevents the cell division that is necessary for healing.
The greater the training intensity and effort, the greater the need for recovery which therefore leads to greater fitness.
Building recovery time into any training program is important because this is the time that the body adapts to the stress of exercise and the real training effect takes place.
Recovery also allows the body to replenish energy stores and repair damaged tissues. Exercise or any other physical work causes changes in the body such as muscle tissue breakdown and the depletion of energy stores (muscle glycogen) as well as fluid loss.
Recovery time allows these stores to be replenished and allows tissue repair to occur. Without sufficient time to repair and replenish, the body will continue to breakdown from intensive exercise.