re: at what age did you have to cut back on your workouts

I am seeing a doctor about it. Checked a few things. Testosterone was on the lower side, but the doctor said he thinks it's ok. Next step is to test for sleep apnea. Some days I really just lack energy all day, like I'm not getting good rest. I actually look like Im in better shape than what I feel, which I assume is the opposite for most men. I'm 37.