Exercise and strength training is good. But trying to become like Arnold Schwarzenegger is not, since it constitutes a type of fakirism which is based on extremes.
You find your own particular rhythm and balance through all components of the spiritual work: cultivating body, speech, and mind. This is about balancing the three brains through a study of the Fourth Way.
As to what type of exercise is best for you, that is something you need to experiment with and verify, yet without being excessive.
For thirty years I sought God. But when I looked carefully I found that in reality God was the seeker and I the sought. -Bayazid al-Bastami