Umar bin Al Khattab (May Allah be pleased with him) would encourage exercise and didn’t like obesity, in fact he was against obesity. He said,
“O People! Beware of overeating because it makes you lazy in your prayer, it makes your body weak and makes you unhealthy and Allah dislikes the obese man. And you should be modest in your food because that is closer to righteousness and further from excess and makes you stronger in worshipping Allah. And you will perish when your desires become more dearer to you than Allah (azza wajal) or your religion.”