Inhibitory Control

We live in a highly individualistic society, a situation that has both pluses and minuses. On the plus side, our children tend to grow up with a sense of freedom to choose their own path in life. On the minus side, a growing percentage of us are burdened by feelings of loneliness and isolation that make us unhappy and have proven consequences for our physical health.

As an endurance coach and nutritionist, I see our society’s hyperindividualism manifest in a sense of exaggerated specialness and uniqueness. Take the “I can’t eat that” phenomenon, for example. Although food allergies, intolerances, and sensitivities are real, these conditions are claimed far more often in some societies and groups than in others—specifically in the most individualistic societies and groups. Asserting the need for a special diet is in many cases a way of asserting personal specialness.

Individualized approach to Endurance training

I see individuality overemphasized to some extent in the training realm too. In the 35 years I’ve been involved in endurance sports, I’ve observed a growing receptiveness to the notion that individual athletes training for the same event (e.g., a marathon) should do so in different ways based on genetic differences that affect how their bodies respond to various training stimuli. Contributing to this trend are studies such as one that was conducted by Canadian researchers and published on the online journal PLoS One in 2016, which found that when subjects were placed on an all-low-intensity exercise program for three weeks and, separately, on an all-high-intensity exercise program during a second three-week period, some subjects exhibited improved fitness only after the former and others only after the later, while only a few improved on both programs and no subject failed to improve on both.

Should we conclude from such findings that individual athletes should indeed take radically different approaches to training for races? I think not. The problem with a radically individualized approach to endurance training is that in essence it amounts to training for what you’re good at rather than training to be good at the specific event for which you are preparing. To return to our earlier example, a marathon is a very long race undertaken at a low to moderate intensity. No matter what your genetic makeup is, you won’t be optimally prepared to run a marathon unless your training features lots of running and frequent prolonged efforts at low to moderate intensity. Training for a marathon with a heavy emphasis on short, high-intensity intervals because you happen to be highly responsive to this type of training is only slightly less absurd than training for a marathon exclusively by chopping wood because testing has demonstrated that you are most responsive to this type of training.

But wait: If your body simply doesn’t adapt to low-intensity exercise, as the above-mentioned study suggests is the case for some individuals, then what benefit can these folks get from this type of training even if it is a marathon they’re preparing for? Good question, the answer to which is that of course every athlete really is capable of adapting to high-volume low-intensity exercise. The Canadian study cited above measured a few select variables such as VO₂max and lactate threshold. But a marathon is not a VO₂max test. So-called non-responders to low-intensity exercise who do not experience an increase in VO₂max in response to this type of training but who do a bunch of it any way will undergo a host of other adaptations, including increased fat-burning ability and heightened resistance to impact-related muscle damage, that are crucial to marathon performance.

This is to say nothing of the neural and psychological adaptations. A runner who routinely does long training runs at low to moderate intensity will see improvements in central fatigue resistance and inhibitory control that he couldn’t gain any other way. Physiology aside, the experience of going long is an essential contributor to the capacity to go long.

The same principle holds for supposed non-responders to high-intensity exercise. A runner of this type who includes a small amount of high-intensity exercise in his training despite deriving no boost in aerobic capacity from it is sure to come away with other benefits, such as increased perceived effort tolerance, that will translate into better performance in real-world competition.

I don’t want to overstate my case. It is undeniably true that each athlete is unique and responds somewhat differently than do other athletes to the same training stimuli. But this individuality is itself overstated in some quarters, and again, even to the extent that athletes are different they must consider the specific demands of the event they’re preparing for before they consider their particular athletic type in deciding how to train.

The proper way to individualize training, therefore, is not to start from scratch with each athlete, inventing from whole cloth the method that is uniquely optimal for that individual. Rather, all athletes should begin by training with the methods that have proved most effective with athletes generally (80/20, etc.) and then fine-tune their formula based on how their body responds to these methods. And fine-tuning never means replacing running with chopping wood.