There's a lot of chatter in the fitness world about what constitutes a great workout. Some folks swear a series of awkward exercises is the key to gains. Others claim a quick jump rope workout that ...

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 ...