In the Chanukah prayers, we say that God delivered the "strong into the hands of the weak." So it is clear that the Maccabees were "weak." In fact they had no military training, since the only people who did not go to war were priests, and the Maccabees were all priests.
This is not to say that they weren't healthy and vital. Maimonides writes: "Having a healthy and complete body is following in the ways of God, as it is impossible to understand and to perceive the knowledge of the Creator when one is sick; therefore people must distance themselves from things that are destructive to the body, and conduct themselves in ways that are strengthening and therapeutic."
Maimonides highly recommends exercise as part of his overall prescription for health. He even ranks it higher than proper diet, saying that, "anyone who exercises and engages in a lot of physical activity, doesn't overeat and maintains regularity, sickness will not come upon him, and his strength will increase, even if he eats unhealthy foods."