Remember the decades-old advice that you if can’t speak while exercising you’re pushing too hard? Forget it. New York Times Well writer Gretchen Reynolds puts the adage to the test of science, specifically, a new study by researchers at the University of New Hampshire, whose results suggest that, for fit people who want to be even fitter, the talk test sets the bar too low. In the New Hampshire test, Reynolds reports, researchers recruited 15 healthy and active men and women ranging in age from 18 to 35 who were fit, but not competitive athletes. The subjects recited the Pledge of Allegiance aloud while jogging on a treadmill at an increasingly brisk pace, while researchers measured their lactate threshold, the point at which the muscles tend to give out. The researchers concluded that if you can talk and run at the same time, you are working at a “moderate” exercise level, which is fine, according to the latest American College of Sports Medicine exercise recommendations, if you are a beginning exerciser who wants to stay a beginning exerciser. Scientifically speaking, the College of Sports Medicine reports that moderate exercise requires 70 to 85 percent of your heart rate maximum, or 60 to 80 percent of your VO2 max. The New Hampshire study found that when fit volunteers recited the Pledge of Allegiance without much difficulty, they were using, on average, 82 percent of their heart rate max and 64 percent of their VO2 max, “at the low end†of the moderate-intensity scale. That’s not enough, says Reynolds, to help an already fit person increase endurance or improve their 5K race time. To do that, she says, you really need a workout that hovers just below your lactate threshold.
Read more from Gretchen Reynolds.