The Runner's Diet
Eating is one of the sublime pleasures of life, right up there with running. If you run well and eat well, you're a happy person indeed; but what does "eating well" mean for runners?
Posted Saturday, 23 March, 2002
Remember how your mom and your second-grade teacher both seemed to latch onto that sime tired phrase, "You are what you eat"? Back then (and maybe even now, too), that would have made you a giant Hostess cupcake. Here at Cool Running, we've made it our mission to make you into a giant carbohydrate, the single most important fuel for the runner.
Despite the legendary junk food binges of marathon great Bill Rodgers, a good diet really does make you perform better; if you follow the basics outlined here, you may find yourself running faster, longer and more efficiently.
Above all, though, enjoy your food. Notwithstanding all the recommendations you'll find in this section, remember that dining is one of the sublime pleasures of life, right up there with running. Use the information you find here as a set of general guidelines, but don't get so caught up in the specifics that you no longer taste your food.
The basic diet
There's really no such thing as a specialized runner's diet. The type of diet that is good for runners is the same healthy diet as that generally recommended for everyone. Trouble is, most Americans seem to fail miserably at staying within that target diet. Though runners generally maintain a better diet than the average Joe, we all need to be aware of the general proportions of our diets.
A healthy diet is one that is high in carbohydrates, low in fat, and sufficient but not excessive in protein. That translates to about 60 percent of your calories coming from carbohydrates, 25 percent from fat, and 15 percent from protein. As in all things, of course, every individual is different and may respond better to slightly different proportions. There is a significant minority of people, for example, who are insulin resistant to some degree. For them, a diet of 60 percent carbohydrates will create big swings in insulin levels and too much fat storage. In that case, a diet of 50 percent carbs, 25 percent fat and 25 percent protein may make more sense.
That said, beware the faddish 40/30/30 diet or the Atkins diet. While many have lost weight following these diets, they are very poor for runners who would find themselves sluggish from the diminished energy stores of such a low-carbohydrate diet. Cool Running strongly recommends that runners follow a high-energy, high-carbohydrate diet. For most, the 60/25/15 diet is a good rule of thumb.
This of course means that carbohydrates should form the cornerstone of your diet. Since carbos are the most important energy source for long-distance running, it's probably no surprise that so many runners eat hefty portions of pasta, rice, bread and potatoes. Some even find that as they exercise more their tastes change to prefer these foods.
More carbos mean more glycogen
Carbohydrates are stored in the muscles as glycogen, the primary fuel you need to keep you moving. When this efficient source of energy wears out, so do you. You hit the wall and can go no further (often after about 90 minutes or two hours of running).
Carbohydrates come in two flavors: simple and complex. The complex carbos are the ones you're after. These are absorbed slowly into your system and give you a steady energy supply. These are the carbohydrates found in cereal, pasta, vegetables and bread (as a dietary bonus, these foods are also generally high in fiber). These should make up the majority of your diet.
Simple carbos, on the other hand, are basically sugars -- tasty and good for a short-term energy boost since they are quickly absorbed into the bloodstream. Unfortunately, the "sugar high" wears off quickly and usually leaves behind a sugar low, complete with reduced performance and energy. Even so, these sugars do have a place in your diet when they come from natural sources like fruit or juice. The worst offenders, though, are the refined sugars -- those typically found in candy, soda, doughnuts, etc. This is literally junk food; plenty of calories and fat, but no essential vitamins or minerals.
A little bit of dessert in moderation is fine, of course, but don't overdo it. If you find that you have a nagging sweet tooth, your body may be trying to tell you that you need more calories. Rather than indulging in a candy bar, you might do better to eat a bit more at meals or add a healthy snack in the afternoon (fruit, cereal or a sports bar).
Trim the fat
If most people need more carbohydrates, it's also true that most should cut back on fat. Not that fat is all bad. It's a necessary part of the diet, offering up both energy and flavor. Still, most of us eat too much of it. Fat should account for only 20 or 25 percent of caloric intake (the average American hovers around 35 percent). While everyone deserves a treat once in a while, try to avoid fatty foods like whole milk, red meat, ice cream, mayonnaise, egg yolks, chocolate, butter and cheese.
Some fats, however, can actually do you some good (though all are chock full of calories). These are the unsaturated fats, particularly monounsturated fats like those in olive oil, peanut oil and avocado oil. Unsaturated fats can actually reduce blood cholesterol. While margarine is made of unsaturated fats, it is also hydrogenated which negates the cholesterol-reducing benefits. Healthwise, there's not much difference between margarine and butter; neither is particularly healthy, and both should be used sparingly (when push comes to shove, tub margarine may be your best bet for reducing cholesterol).
When it comes to fat, the real bad guys are the saturated fats. These come primarily from animal sources such as red meat and milk, but also from coconut, palm and vegetable oils. They are closely linked with heart disease, obesity, diabetes and some cancers. Try to keep saturated fat down below 10 percent of your total calories, or around a third of your total fat intake.
Protein: Beware too much of a good thing
Your protein intake should be a bit lower, at 10 to 15 percent of total calories. This may seem odd, since many of us grew up on the myth that high-protein diets were the essential building blocks for any athlete. In fact, your body stores excessive protein as fat. If you really overdo it, by taking too many protein supplements for example, you could even damage your liver or kidneys. All of which is simply to say beware too much of a good thing. And proteins are, after all, a good thing. They help bone and tissue to grow and repair, and they're the stuff that blood, skin, hair, nails and organs are made of. Proteins are literally body builders, and it's important to get a sufficient amount.
In fact, since you burn some protein as fuel when you exercise, runners need a bit more protein than non-runners. Endurance athletes, for example, average one and a half to two times the RDA for protein. A good rule of thumb is to eat about half a gram of protein daily per pound of body weight. Good sources of protein are fish, lean meat, poultry, beans, nuts, whole grains, egg whites, low-fat milk, low-fat cheese and some vegetables.
Vegetarians, in particular, should be careful to get enough protein. While study after study has demonstrated that a vegetarian diet promotes health, it must be carefully planned to compensate for the nutrients you would otherwise get from animal sources. For some athletes, fatigue and poor performance have been a result of switching too carelessly to a vegetarian diet. In addition to stocking up on proteins (with cereals, whole grains, legumes, and nuts for example), vegetarians should also seek alternative sources for iron and zinc.
The big picture
In the end, a good diet is a lot like a good training program. Over the long haul, a sound nutritional routine will deliver strong results and increased performance, in the same way that a balanced workout program gradually improves your conditioning. Since both are much more important over the long run than in the short, your diet, like your training program, should be viewed in the big picture. It's difficult to derail yourself nutritionally over the short term. A few days of epicurial indulgence will not ruin your racing form any more than taking a few days off from your training routine. Don't be anxious about the day-to-day. Always keep the big picture in mind.