If Your Exercise Routine Isn’t Making Any Difference, You May Be a ‘Non-Responder’

Photo: Camerique/ClassicStock/Getty Images

First, let’s get the bad news out of the way: If you’ve been plugging away at the same workout for what seems like forever and you still aren’t seeing much of a change, there’s a good chance you never will. And it’s not for lack of effort, or because you’re doing it wrong — it’s just a quirk of your own unique biology.

As the New York Times explained earlier this week, there’s a name for that in exercise science: “non-responders,” people seemingly immune to the beneficial effects of a given workout. In 2001, an analysis of several previously published exercise studies found that a single exercise routine could affect different people in dramatically different ways, regardless of age, gender, or other demographic factors. Some may build up their stamina from a running routine, or build up muscle mass from lifting weights, but others might see their fitness levels remain stagnant, or even end up worse off than when they started.

Now for the good news: A study recently published in the journal PLOS One makes the case that there’s no such thing as a universal non-responder — meaning if your current routine isn’t working for you, there’s one out there that will.

The study authors had their subjects go through three weeks of endurance training and three of interval training, with a few months’ break in between the two, and measured each person’s fitness at the beginning and the end of each program. The results: “As a group, they had gained admirable amounts of fitness from both workouts and to about the same extent,” the Times wrote. “But individually, the responses varied considerably”:

About a third of the people had failed to show much if any improvement in one of the measures of fitness after three weeks of endurance training. Similarly, about a third had not improved their fitness much with interval training. And after each type of workout, some participants were found to be in worse shape.

A majority of the participants, in other words, had failed to respond as expected after one of the workouts.

The researchers’ main takeaway, though, is that each participant had at least one workout that did work for them — being a non-responder to one type of exercise never meant that someone was a non-responder to all types.

One more bummer in this bright spot: The only way to really tell if you’re a non-responder to something is through trial and error, meaning you’ll have to slog through a few weeks’ worth of fruitless gym sessions to know for sure. The light at the end of that miserable tunnel, though, is that sooner or later, you’ll inevitably hit on a workout that works.

You Might Be a ‘Non-Responder’ to Your Workout Routine