From the yogic perspective, the Spirit is never actually really lost but merely obscured by our misconceptions, afflictive emotions, and other impurities. When we start purifying our body and cleansing and polishing the mirror of our mind, we gradually recover our spiritual identity, which until then lay buried. Unfortunately, our busy lives seldom allow enough time during the day to do this sort of inner polishing effectively. Since ancient times, therefore, Yoga has recommended that we drop out long enough for the nervous system to wind down to the point where we can breathe freely and remember ourselves that is, recover our Spirit. The body-mind knows how to replenish itself when it is placed in the right conditions.
Rejuvenation occurs when the mind is able to rest, unencumbered by thought.
The body heals itself when it is no longer being stressed. When the mind is quiet and the body is still, an underlying freshness spontaneously springs forth. That freshness is of the Spirit. For our mind to function well, it needs an environment that is uncluttered, healthy, soothing, and conducive to a contemplative life. In other words, to rejuvenate mentally, we require an environment that makes little demand on us for outward activity but provides all the necessary means for focusing inwardly through deep relaxation, breath work, and meditation.