According to Maharshi Charak-
Laghawam Karmasamarthyam Sthairya Duhkha Sahishnuta | Doshakshayoognivraddhishca Vyayamadupa jap ate||
Meaning: Physical exercise gives lightness to the body, increases its stamina (for hard work), stability and potential for tolerance. It helps in elimination of the bodily deficiencies and defects and augments the appetite. As per the scripture named "Bhav Prakash"