“I just don’t respond to that type of training.”
Or if you are a science nerd among us, you might say, “I have the non-responder genes for aerobic (or anaerobic) exercise”
It’s a convenient excuse, and perhaps with a hint of truth. In fact, researchers have suggested that up to 20% of individuals are non-responders to aerobic exercise, so is it a valid concern?
Instead of an excuse, the idea of a non-responder is a convenient stop sign to evaluation. If we label someone as a non-responder, then we are definitively stated that our intervention does not work for that person. Whether that intervention is an altitude training stint or a particular type of speed or endurance training, if we label our individuals who show no improvement, then we can gloss over the hard questions. We don’t need to ask why they don’t respond. We already have the answer. We move on, shrugging our shoulders and saying “Hmm, guess it doesn’t work for you, try something else.”
It’s not exactly an inspiring message. And it’s likely not true. There is no such thing as non-Responders. Only misapplied stimulus.
Volume Cures All?
In a recent study, Refuting the myth of non-response to exercise training, researchers put the non-responder theory to a test. They took subjects through a 6 week training program where they were split into one of five groups. The first group exercised 60 minutes a week, the 2nd 120 minutes, and so forth all the way up to 300 minutes a week for the final group. They then tracked their improvement in maximal power output, Vo2max, and a few other parameters.
After the 6-week training block, they took the individuals who saw no improvements–those who would be labeled as non-responders in any study– and put them through another 6 week training block. The difference, though, is that they boosted their training by 120 minutes a week.
Six weeks down the line, everyone improved. The non-responders had been eliminated. Miraculously, everyone was a responder.
Along similar lines, the researchers found that the percentage of non-responders decreased as the volume of exercise increased. The 60min per week group had 69% non-responder rate, 120min had a 40% rate, 180min was 29% and the 240 and 300min groups has 0%.
In other words, the dose determined the response rate. The low volume groups didn’t have the necessary stimulus to improve the subject’s performance or aerobic abilities. It’s not that they were non-responders to the aerobic training; it was that they didn’t have enough of it to push them to a new level.
I’d be willing to bet that if the originally discussed study kept increasing the volume of aerobic exercise per week, the non-responder rate would increase. It’s not that these individuals are a non-responder to high volumes of aerobic training, it’s that the stimulus would be too much for some to handle. They would “not respond” to the higher volumes.
It’s not just volume that matters. In another study, researchers found that increasing the intensity of the training eliminated the non-responder result. In a different study, the responsiveness to resistance training in elderly subjects was dependent on the duration of the exercise intervention.
The dose makes the poison.
Or in running terms, the stress (and recovery and context) make the adaptation.
We all know this intuitively. We need an adequate stimulus to “overwhelm” or “embarrass” the body so that it adapts. If the stimulus is too high or too low, we don’t get the subsequent output (or adaptation) that we want.
In other words, If you don’t respond, it’s likely that the stress was too much or too little, or applied in the wrong direction at the right time.
We all respond, just not to the same degree. We have some who are super-responders who grow muscle when simply looking at a weight, or get aerobically fit within the first week of running. We have others who are great athletes, but it takes them a long meticulous 5 month build up to reach that fitness. If you’ve coached at all levels, you’ve seen all of these phenomenon in action. The super-responder who comes off of 5 months of injury, runs a few times and is in near top shape. The “stud” who like normal until he gets a solid block of training in. In his book, The Sports Gene, Dave Epstein has a fantastic chapter on this subject.
As a coach, you’ve also likely seen that non-responders don’t exist. As a High School coach, you’ve seen the out of shape, low talent athlete, who is determined but appears as if they must have a single mitochondria in their entire body. They are not aerobic beasts. Yet, with enough training, you might see that 7 minute mile drop to 6:30.
Everyone responds, they just need the appropriate stimulus.
When it comes to adapting to altitude, the phrase non-responders also gets slung around. Did your hemoglobin mass increase after altitude? Then you are a responder, if not, well, sorry. Once again, this is a great example of the stimulus being important.
Perhaps the athlete didn’t respond because the altitude was too high or too low. Or maybe their iron stores were low, or they were overtrained going into the trip. Or maybe, just maybe, their stress levels were too high. When I was working with a group of endurance athletes who went to altitude, I noticed a peculiar thing in the handful who didn’t respond. They had consistently elevated cortisol levels going into the trip. While this is simple correlation and needs research to truly evaluate it, the practical takeaway was clear. Altitude is a stressor that we have to adapt to, and if athletes aren’t seeing the bump in red blood cell mass that altitude is supposed to deliver, we need to look into why the stimulus is wrong.
And that’s the main point, we may have low or high responders, quick or slow responders, but it is exceedingly rare to have non-responders.
Labels matter. If we label something or someone as a non-responder, it pushes us towards a stop sign in our mind. We don’t ask the follow up question of why they might not be responding. We settle with the easy, convenient answer; that they just aren’t meant to.
Maybe, they just don’t have the right stimulus to respond.
For more information on this topic, here’s another blog I wrote a few years ago.