I noticed this issue in my 40's - exercise didn't have the same reliable effect. Got heavy and had/have a hard time getting it off. Still too heavy but working on it. Keep active and biking has been a the best exercise of all because it doesn't beat up the body like running or bball. It helps with the cardio, lungs and overall stamina - and the core. Lately been reducing carbs and focusing on eating protein (don't worry about fat at all) - sort of like an Atkins diet. That helps for me.