As a second language speaker, when I first see the word sexercise, I thought it’s a made up word for fun.  Saying sex is a kind of exercise which, just like ordinary exercise, it strengthens your heart, it helps to tone your muscle and stuff like that.  But when I look it up, this word is not new and sex-ercise does seem to help improving your health.  Here is what I found after a little bit of research on the net.