9 Ways to Tell If You’re Exercising Enough

What it means: Unless it's supposed to be an easy recovery session you're probably exercising at too low of an intensity.

How to adjust: Sport a heart-rate monitor and check in to see if you're working out in the right zone. Hitting the weights? Don't put them down until you notice your form slipping or can't lift them without shaking; those are signs you've done enough, says Minardi.