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Most endurance athletes, like most non-endurance athletes, don’t eat as well as they should. The minority of endurance athletes who do eat as well as they should reap a variety of rewards, including better workout performance, faster post-workout recovery, lower body fat levels, and reduced injury risk.
If you want to enjoy these same rewards, you may need to change your diet. There are two general ways to approach this process. One way is to replace your diet with a new and better one. The other is to simply improve your existing diet. Both scientific and real-world evidence suggest that the second approach is more effective. In particular, recent advances in the psychology of habit change indicate that dietary modifications are more likely to stick if they build upon existing routines and preferences rather than replacing them wholesale, as most popular diets require.
Building Better Habits
A diet is simply a collection of eating habits. As everyone knows, habits of all kinds are difficult to change. Nevertheless, people succeed in changing their habits every day. What are the factors that account for these successes? One of them is what I like to call the principle of minimal disruption. According to this principle, a person is more likely to succeed in changing a habit if he or she changes it to the smallest degree that is necessary to achieving a goal. Applied to diet, the principle of minimal disruption calls for us to change our eating habits to the smallest degree necessary to achieve our health and fitness goals.
There is plenty of research showing that altered eating habits are most likely to last when they are least disruptive. For example, a 2007 study by Stanford researchers comparing the effects of four popular weight-loss diets with widely varying ratios of carbohydrate, fat, and protein found that long-term adherence was pretty good for subjects who were randomly placed on a diet whose ratio was reasonably close to that of their current diet and was abysmal for those who were randomly placed on a diet that required drastic changes in their accustomed macronutrient balance.
Of course, the diet you’re most likely to stick with is your current set of eating habits. But your current set of eating habits is not providing the health and fitness outcomes you seek. So you’ve got to change something. What, then, is the smallest degree of change that will do the job?
There are only two things you absolutely must do with your diet to get the results you want. The first is maintain high diet quality. This means getting most of your nutrition from natural, unprocessed foods from every major food group. The other thing you must do with your diet is eat enough to fully satisfy your body’s energy needs but not so much that you accumulate or fail to shed excess body fat.
These two musts leave all kinds of wiggle room. There is an almost infinite variety of different eating habits that fall within the parameters they establish. The likelihood of you sticking with a diet that obeys the two musts will be greatest if you exploit this wiggle room in a way that indulges your personal tastes and preferences, cultural norms, and lifestyle. The smart way to eat better, therefore, is not to trade your current diet for a one-size-fits-all popular diet but rather to measure your current diet against the standard of the two musts and tweak it as necessary to bring it up to standard.
If you were to pick up and skim through any given popular diet book, you would probably find that its author had absolutely zero interest in your current diet—what you like, what you don’t like, what agrees with you, and what doesn’t. Regardless of which specific diet is being peddled in the book, the underlying message is, “This is the way you have to eat. Abandon your current way of eating and start over with this diet.”
By contrast, in my work as a sports nutritionist, I ask clients lots of questions about their current eating habits and then I suggest specific ways to make them better, applying the principle of minimal disruption. I find this approach to be more humane, more pragmatic, and more effective.
The Cheeseburger Example
In large part, the process of improving a diet rather than replacing it consists of adopting healthier versions of preferred foods and meals. Take cheeseburgers as an example. Suppose you have a weakness for fast-food cheeseburgers and you eat them often, despite knowing full well that they are unhealthy.
Many popular diets would require you to give up eating cheeseburgers entirely. The meat patty disqualifies this food for vegans, the bun prohibits it for Paleo dieters, and so forth. But the principle of minimal disruptions allows you to continue eating cheeseburgers, requiring only that you make your own healthy ones at home instead of grabbing them at the drive-thru window.
A standard fast-food cheeseburger is made with processed beef, processed cheese, a white-flour bun, and nothing much in the way of vegetables. All of these foods are harmful to health. A healthy cheeseburger comprises a grass-fed beef patty, real cheese, organic tomatoes, lettuce, onions, and pickles, and a 100-percent whole-wheat bun. All of these foods are beneficial to human health.
And I’ll guarantee that this healthier cheeseburger also tastes better!