Have you ever heard that completing 40 push-ups a day can significantly lower the risk of cardiovascular disease? Push-ups are an effective and simple way to measure upper body strength and endurance.

Push-ups always came easy to me. In my 20s and 30s, I could crank out more than 30 a day if I wanted to, and I loved how strong they made me feel. But the other day, when I went to do a set of 10 push ...