How can you tell whether your workouts are at the proper intensity?

Too little exertion can be a waste of your time and sweat. You won’t burn enough calories to lose any significant amount of weight. And you won’t challenge your heart and other muscles enough to make them grow stronger.

But too much exertion can lead to overtraining — in which you essentially burn yourself out — and can lead to injuries, whether it be a specific incident or an overuse injury, such as bursitis.

So how do you know?

Experts at Life Fitness suggest these ways to gauge the intensity of a workout:

The Talk Test. Are you able to have a full, comfortable conversations during your workout? If so, you might not be challenging your body enough. On the other hand, if you’re gasping for air, that’s likely too intense. A workout that makes you limited to broken sentences is just about right.

Perceived rate of exertion. This is a measure of how hard we think we’re working. The American Council on Exercise equates this rate of exertion on a scale of 0 to 10. Three to 5 is the recommended workout zone, where lying on the couch is a 0 and sprinting after a runaway dog is a 10.

Target heart rate. With the help of a heart-rate monitor, this can be the easiest way to gauge intensity. During a workout, maintain 50 to 80 percent of your maximum heart rate, which is 220 minus your age.