A professional endurance athlete's livelihood depends on their performance, and endurance performance depends largely on training. The sports of cycling, running and triathlon are so competitive today that a pro competitor cannot perform well enough in races to pay the bills if they use inferior training methods. No amount of talent can overcome an outdated approach to training.
This is why nearly all professional endurance athletes of our time train more or less the same way. For example, the vast majority of elite runners run twice a day, do about 20 percent of their training at moderate and high intensities, and reduce their training load for recovery every third or fourth week. These and other universal practices have spread throughout the highest ranks of the sport because they work better than the many other training methods.
Training isn't the only factor that affects endurance performance. Diet does too. Today's professional endurance athletes cannot expect to win despite a poor diet any more than they can expect to win despite inferior training methods. The dietary practices that are most widely shared by top cyclists, runners and triathletes must be those that are most beneficial for endurance performance.
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Many sports nutrition experts don't look at the matter of optimal diet for endurance performance this way. Instead of observing what the elites do and judging it best by definition, they start with some theory about what ought to work best and insist that it does, regardless of what the best athletes actually do.
Some say a vegan diet is best for endurance athletes because meat clogs the arteries. Others say the Paleo Diet is best because it unlocks our genetic potential. Still others say the Zone Diet is best because it balances the energy sources perfectly. And there are many other theories.
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Which Diet Do Pros Follow?
So, which one among the dozens of theory-based diets are most professional endurance athletes actually following? The answer is none of them. Very few elite endurance athletes follow diets with names. Instead, the elites typically practice agnostic healthy eating.Agnostic healthy eating is a diet in which no food groups are excluded, no nutrients are marginalized, and special rules are followed, but in which the overall quality is very high. It's a flexible, inclusive way of eating that is culturally normal yet far from average.