You know that friend who seems to eat pizza and stay skinny while you gain weight just looking at carbs? The same thing happens with exercise. I have a buddy who can knock out 200 push-ups and burn ...

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 ...

Someone with a well-functioning thyroid might burn 100 calories in 250 push-ups, while another person with a sluggish thyroid needs 400 reps for the same result. I’ve worked with people who struggled ...