It not only keeps the body physically and mentally fit but also provides recreation and mental relaxation. It is nature' best tranquilliser.
" Exercise produces chemical and psychological changes that improves your mental health. It changes the levels of hormones in blood and may elevate your beta-endorphins(mood-affecting brain chemicals). Exercise may also improve the function of the autonomic nervous system."
Exercise also gives a feeling of accomplishment and thus reduces the sense of helplessness. Some form of active exercise, must be undertaken each day at a regular hour.
To be really useful, exercise should be taken in such a manner as to bring into action all the muscles of the body in a natural way.
Walking is one such exercise. It is, however, so gentle in character that one must walk several kilometres in a brisk manner to constitute a fair amount of exercise.
Yogic asanas such as vajrasana, bhujangasana, shalabhasana, halasana, paschomittanasana, sarvangasana and shavasana and pranayamas like kapalbhati, anuloma-viloma and bhastrika are highly beneficial in the treatment of depression.