If you ain't sweating, you ain't working hard enough.

The next time you're in the middle of a run or a yoga class, take a second to pause and ask yourself how you feel, not just emotionally, but physically. How fast are you breathing? Could you have a conversation with the person next to you? Could you sing along to the music coming out of your headphones? 

Here's a chart inspired by the folks at Harvard Medical School that sums up the easiest way to gauge your workout?

The chart is based on a categorization called "perceived exertion," a self-guided way of measuring how hard you're working your body. According to the Centers for Disease Control and Prevention, this strategy is one of the best ways to assess the intensity of a bout of physical activity. It can be especially handy for people taking medications that can affect heart rate or pulse. 

As you continue to workout and get more fit, you'll find that your judgment of an activity's difficulty will shift. That intense, one-hour yoga class that you used to be barely capable of finishing might start to feel like a moderate workout, for example. As this happens, you can gradually work your way toward harder and more intense activities and goals. So get out there!

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