Stop us if you’ve heard this one before: You should be able to have a conversation with someone (or sing “Happy Birthday”) while you run or work out. But is that true… or should you be pushing yourself at a higher intensity? According to experts: It depends. Utilizing the talk test for exercise is a pretty standard measure of effort and intensity in the training world, particularly for pregnant people.

And it’s not super complicated to discern what it means. Being able to have a conversation usually indicates that you’re working out at a sustainable effort you could do for a long-ish period of time. Being out of breath means that you’re performing a higher intensity workout (like HIIT, for example) that you should plan on doing for a much shorter period of time (with a good bit of rest afterward).

“Intensity is a frequently overlooked component when exercising,” says physical therapist Sridhar Yalamanchili, PT, MSPT, with Atlantic Spine Center in New Jersey. But how do you know your intensity without the help of a heart rate monitor? “A good measure of exercise intensity is being active in the target heart rate range. Not being able to hold a conversation while exercising is a good piece of advice…[because it ensures] the right intensity,” says Yalamanchili.

In other words, if you can’t talk or sing, that’s a pretty good indicator that you’re at a rather high intensity. agrees. “Someone running for recovery [at a slower pace] will be taking it pretty easy, and talking should be no problem,” explains Nell Kucich, a trainer at Bout Boxing in Roslyn, NY. “Whereas if you are training for speed or lactate threshold [at a deliberately higher intensity or faster pace], then by design it should be pretty hard to get a word in.” And, she says: “If it’s not, then you could probably be digging a little deeper.”

This, she says, is determined by your goals—whether you’re increasing endurance, looking to gain strength, or promoting muscle recovery after a hard workout. So not every workout needs you to be breathless. Your intensity, in turn, “dictates how much energy is left for chatting.”

If you’re on a moderate run, or simply doing your standard Wednesday workout (whatever that looks like for you), you might be somewhere in the middle, says Kucich. Or as she puts it: “Simply in it for a good sweat and endorphin boost.” In this case, “It all comes down to your fitness level. If you’re at a challenging pace and can still hold a conversation, go for it!”

Ready to get to it? Here’s a workout to try today:

Oh hi! You look like someone who loves free workouts, discounts for cult-fave wellness brands, and exclusive Well+Good content. Sign up for Well+, our online community of wellness insiders, and unlock your rewards instantly.