Is your workout not working?

Is your workout getting you nowhere?

Research and lived experience indicate that many people who begin a new exercise program see little if any improvement in their health and fitness even after weeks of studiously sticking with their new routine.

Among fitness scientists, these people are known as “nonresponders.” Their bodies simply don’t respond to the exercise they are doing. And once discouraged, they often return to being nonexercisers.

But an inspiring and timely new study suggests that nonresponders to one form of exercise can probably switch to another exercise regimen to which their body will respond. And a simple test you can do at home will help you determine how well your workout is working for you.

One of the first major studies to report the phenomenon of nonresponders appeared in 2001, when researchers parsed data from dozens of previously published studies of running, cycling and other endurance exercise.

The studies showed that, on aggregate, endurance training increased people’s endurance. But when the researchers examined individual outcomes, the variations were staggering. Some people had improved their endurance as much as 100 percent, while others had actually become less fit, even though they were following the same workout routine.

Age, sex and ethnicity had not mattered, the researchers noted. Young people and old had been outliers, as had women and men, black volunteers and white. Interestingly, nonresponse to endurance training ran in families, the researchers discovered, suggesting that genetics probably plays a significant role in how people’s bodies react to exercise.

Since then, other researchers have found that people can have extremely erratic reactions to weight training regimens, with some packing on power and mass and others losing both.

And a study published last year concentrating on brief bouts of intense interval training concluded that some people barely gained endurance with this type of workout, while others flourished, greatly augmenting their fitness.

These studies, however, were not generally designed to tell us whether someone who failed to benefit from one form of exercise might do well with another.

So for the new experiment, which was published in December in the journal PLOS One, researchers from Queen’s University in Kingston, Ontario, and the University of Ottawa decided to focus intently on whether a nonresponder to one form of exercise could benefit by switching to another.