A once a week, 60 minute lunchtime yoga class resulted in "marked improvement in feelings of clear mindedness, composure, elation, energy and confidence" during a recent workplace trial. The British university study concluded that even a short term yoga program can improve emotional well being and resilience to stress. The authors suggest that employers consider offering yoga classes to their employees.
SOURCE: "The Effectiveness of Yoga for the improvement of Well-Being and Resilience to Stress in the Workplace" by N. Hartfiel et al., Scand J Work Environ Health 4/6/10