Why The Same Training Plans Work Differently For Different People

A number of factors determine how different athletes respond to the same training stimulus.

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We all know that person: the friend who does the same training and workouts we do, yet goes from couch potato to speed demon, while we keep plugging along without nearly as much improvement.

It seems like a mystery. They must just be naturally more talented or secretly working harder or it must be something else we’re doing differently, because if we’re truly on the same training plan, why wouldn’t we experience the same type of success?

“Just as we’ve learned you might need three Tylenol and I only need one,” says David Epstein, author of The Sports Gene: Inside the Science of Extraordinary Athletic Performance, we’ve also learned that some people need different training than others.

“The analogy would be: ‘Why do different diets work for some people and they don’t work for others?’” says Tom McGlynn, a three-time Olympic Trials qualifier in the marathon and founder of RunCoach, an online coaching program. Sure, part of why that diet doesn’t always work is that two people might not be following it exactly the same way. Part of it is that diets don’t take into account all the other life factors that go into losing weight. And part of it just comes down to genetics.

The HERITAGE (HEalth, RIsk factors, Training And GEnetics) Family Study tried to answer this question by putting multiple generations of different families, all of whom were relatively inactive, through the exact same training regime. What the study found was that after five months of the exact same exercise protocols, all completed and monitored in lab settings, some of the people saw 50 percent increases in their VO2 max, some had moderate increases and some had almost no changes in their VO2 max at all. What was interesting, says Epstein, was that how they responded to the training had very little to do with how naturally high their VO2 max was at the start. In fact, some of the people who started out more naturally talented were overtaken by others during the training. What a person’s training response most correlated to was what family they were in.

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Researchers have since found that there are a number of genes that correlate with how we respond to exercise or training. Those genes, for instance, impact how quickly you build mitochondria and the structure of your EPO receptors, which in turn impacts how quickly you get faster.

Knowing that genetics play a role in how we respond to training doesn’t do most of us much good, though, for a couple reasons. Many people are just never going to get the intensive genetic testing or muscle biopsies or high-level blood work needed to figure out what they might be biologically predisposed toward.

But even if we could, there’s no guarantee it would answer all our questions. While scientists know that there are a number of gene markers that correlate to our trainability (as well as to plenty of other things), they don’t know exactly how all those genes work together. And the over-the-counter genetic tests that people can buy, says Epstein, are mostly just hype and don’t really tell you how those genes work.

“There are a couple hundred genes that go into being an Olympic runner. Here is one piece of 1,000 pieces,” he says. “That doesn’t tell you anything about the picture.”

That means you’re probably going to have to figure out what works best for you the old-fashioned way.

“A lot of it is going to be trial and error,” explains Jason Fitzgerald, a 2:39 marathoner, coach, and author of the blog Strength Running.

While there are trends in training that come and go, there are also general rules that have almost universal applications. For example, most coaches believe that periodization is the best way to prepare for a race. What works for you within those periods might depend on you, but if you think you’re responding better to high-intensity speed work while your friend seems to excel on high-volume training, it might not just be your imagination.

“The devil is in the details,” says Fitzgerald.

On a practical level, there are also plenty of reasons you might not respond the same as your friend following the exact same training plan, regardless of genetics.

People tend to underestimate the amount that recovery impacts their improvement. You and your friend could be following the same training plan, but sleeping different amounts or dealing with different levels of overall stress. “That’s a big difference,” notes McGlynn.

There’s also the fact that you and your friend aren’t the same, and not just genetically. You also have different histories and athletic backgrounds.

“Some runners are ready to start a particular training plan and others aren’t,” says Fitzgerald, which is why he always puts new athletes through an intense questionnaire before he starts developing an individualized training program.

You don’t want to start a high-volume plan aimed at running a sub-3-hour marathon if you’ve never even run before, just as you don’t want to jump right into high-intensity speed workouts if it always results in injury. Yes, you might respond best to a certain kind of training, but for most runners it makes sense to start with a basic plan and customize from there, based on how you respond to different stimuli.

“It’s more important to have a plan that has a basis on your individual ability level,” says Fitzgerald.

Then, as you try different things, you’ll start to figure out what works for you. Just because your friend seems so much faster than you right now, doesn’t mean you can’t eventually surpass them—you just might have to take a different route to get there.


About The Author:

Kelly Dunleavy O’Mara is a journalist/reporter and former professional triathlete. She writes for a number of magazines, newspapers, and websites. You can read more about her at