We exercise our bodies to increase strength and endurance, promote general health, and keep unnecessary weight off.  Spiritual devotions are like exercise for our souls. They re-direct our attention off of distractions and unto God’s purposes and promises. (Source)

Other forms of devotionals like self-affirmations may also help to mitigate the effects of stress. In one study, a short affirmation exercise boosted the problem-solving abilities of "chronically stressed" subjects to the same level as those with low stress. What's more, affirmations have been used to successfully treat people with low self-esteem, depression, and other mental health conditions. And they have been shown to stimulate the areas in our brains that make us more likely to effect positive changes in regard to our health. This latter study suggests that a stronger sense of self-worth makes you more likely to improve your own well-being.(Source)