Srimad Bhagavatam Canto 11, Chapter 28, Text 43

SB 11.28.43

yogam nisevato nityam
 kayas cet kalpatam iyat
tac chraddadhyan na matiman
 yogam utsrjya mat-parah
 
Translation: 
 
Although the physical body may be improved by various processes of yoga, an intelligent person who has dedicated his life to Me does not place his faith in the prospect of perfecting his physical body through yoga, and in fact he gives up such procedures.
 
Purport: 
 
A devotee of the Lord keeps his body fit by eating nourishing Krsna prasadam, by maintaining a clean and regulated life, free from unnecessary anxiety, and by chanting and dancing before the Deity of the Lord. When a devotee is sick, he accepts medical treatment by normal methods, but beyond this there is no need to absorb one’s mind in the physical body in the name of so-called yoga practice. Ultimately one must accept the destiny that has been ordained by the Lord.
Srimad Bhagavatam Canto 11, Chapter 28, Text 42
Srimad Bhagavatam Canto 11, Chapter 28, Text 44