Buddha pointed out that there are several benefits of exercise including:
- increased resistance to disease
- good digestion
- increased composure
“Monks, there are these five benefits of walking up & down. What five? One is fit for long journeys; one is fit for striving; one has little disease; that which is eaten, drunk, chewed, tasted, goes through proper digestion; the composure attained by walking up & down is long-lasting. These, monks, are the five benefits of walking up & down.” 
The Buddha also explained the benefits of mindful eating thus:
“When a person is constantly mindful,
And knows when enough food has been taken,
All their afflictions become more slender
— They age more gradually, protecting their lives.” 
 ‘Cankama Sutta: Walking’ (AN 5.29), translated from the Pali by Aggacitta Bhikkhu & Kumara Bhikkhu. Access to Insight (Legacy Edition), 2 November 2013.
 ‘Donapaka Sutta: King Pasenadi Goes on a Diet’ (SN 3.13), translated from the Pali by Andrew Olendzki. Access to Insight (Legacy Edition), 2 November 2013.