Exercise intensity doesn’t come in a one size fits all number, and it can be as individual as choosing the best way to eat an Oreo. Intensity is different for everyone, but the higher the heart rate during physical activity, the higher the intensity, so measuring heart rate can be a good judge. The Department of Health and Human Services recommends Physical Activity Guidelines for Americans include 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic activity every week.

But what does moderate and vigorous mean exactly?

Heart-rate training, which can be done in a variety of ways, can determine if the aerobic activity is too easy, too hard, or just right. There is the old fashioned way by finding the carotid (neck) or radial (wrist) artery, taking the pulse for six seconds and multiplying by 10 to figure out the heart rate. It’s also necessary to do some math beforehand to figure out the individual target heart rate. For the techies, the gadget route is another way to go, by using a heart rate monitor. Then there is the RPE (Rated Perceived Exertion) where intensity is based on a scale of zero to ten, with zero signifying a potato sitting on a couch somewhere. But research suggests that the easiest way to measure intensity may also be as accurate, and all it takes is a little bit of talking.

The study took 16 healthy and moderately active people and had them exercise on a stationary cycle and a treadmill. They were hooked up to monitors to determine heart rate and exercise intensity, and they were also asked to perform a talk test where they said the Pledge of Allegiance during specific times throughout the exercise. At moderate intensity, the subjects were able to speak at a comfortable rate, and when exercise intensity went above and below moderate, the ability to talk was well matched to the heart rate monitor readings.

It turns out there is a close correlation between the talk test and the heart rate monitor measurements, indicating that the talk test is a cool tool to monitor exertion and measure exercise intensity.
The talk test works because talking comfortably means breathing frequency, which is related to heart rate, is under control. Even though the talk test is subjective, being able to talk comfortably and therefore breath comfortably, indicates a moderately intense workout. If the words don’t flow as easy, where a breath is required after every word, the workout crosses over into the vigorous range, and on the flip side, if singing show tunes is involved, the workout may be too easy, and the heart isn’t working hard enough to reach the target rate.

Hitting the target heart rate is important to any aerobic activity, and with the talk test there is no need to revisit seventh grade math and no need to spend any money. All that is required are vocal cords and the ability to talk, talk, talk, by reciting a few verses from a favorite rhyme, saying, or song. Choose timed intervals throughout the exercise and start talking, paying attention to how easily the words come out.

The best part is there are no failing grades with this test.