Having reached my mid-40s, I've come to the conclusion that eating well is the best tonic for anything that ails me. When I get busy with work and feel too lazy to cook properly I end up scarfing down fast food, and if I do that for a few days in a row I feel like crap, and no rest or training program helps.

Eating right. "Mostly plants, not too much," as the saying goes. Actually, for me eating right means cutting out white flour-based things like breads and pastas completely, and getting carbs from things like steamed sweetpotatoes/yams.