Mysticism and Metabolomics: How Food Influences Athletic Performance
December 29, 2014
Eat to Win.
Apart from being a popular book, this simple three-word phrase encapsulates an idea that every athlete intuitively knows: if you eat the right foods, you will perform better.
In the late 70s, many endurance athletes believed what John L. Parker immortalized in his novel Once A Runner: “If the furnace was hot enough, anything would burn.” Marathoner Bill Rodgers admitted his fuel for winning the Boston and New York Marathons four times each consisted mainly of “mayonnaise, sugary breakfast cereals, chocolate-chip cookies, snack chips, soft drinks and gin-and-tonics.”
Meb Keflezighi, 2014 Boston Marathon winner, on the other hand, keeps a strict diet of whole grains, lean meats, vegetables and fish and almost never has dessert despite having a “very sweet tooth." And it is not just endurance athletes watching their food. John Elway completely revamped the Denver Broncos’ kitchen to provide strictly controlled meals to his players.
Those of us for whom John Elway has not yet bought a personal chef – I am holding out hope – are left to figure out that winning recipe for ourselves. Sometimes we get help, though. Olympic swimmer Michael Phelps uses 4000 calories worth of Subway sandwiches per day. Argentinian soccer star Lionel Messi advocates half a bottle of Gatorade — and spilling the other half all over yourself. Broncos quarterback Peyton Manning would have us believe the secret is chicken parm sandwiches and a heavy dose of the Nationwide Insurance jingle.
Kidding aside, there is a lot of information out there about what foods can help you recover from a hard workout, give you a boost of energy, or keep your body from getting sick, and not all of it is accurate. That is where David Nieman comes in. He and his colleagues at the Human Performance Laboratory (HPL) at the North Carolina Research Campus investigate how different foods affect athletic performance in laboratory conditions.
Nutrition science has come a long way since the 1970s. Lean proteins, vegetables and whole grains all contribute to a healthy body but HPL scientists take this a step further. They identify specific molecules in these foods and, using a science called metabolomics, search the body for chemical traces of the desired outcome.
Metabolomics applies rigid quantitative measures to a science that many amateur athletes approach with mysticism and apply by feel.
I ran cross country and track in college, and my team had as many nutrition and training philosophies as we had runners. One thing most of the team agreed on, however, was a concept called “sober October.” The idea was that as cross country season ramped up, we would swear off all alcohol and, as a reward, our bodies would recover better from races and workouts and our “sacrifice” would receive some sort of karmic recompense in the form of racing well in the November Championships.
There is some science to that. Alcohol does hinder muscle recovery, but there were other factors that we did not consider when we brought all that Gatorade to parties. In some ways, that beer we did not drink could have helped us. HPL performed a study comparing runners who drank non-alcoholic beer every day leading up to a marathon to those who drank a placebo. Intense running temporarily weakens the immune system, but polyphenols in the non-alcoholic beer actually protected runners from developing respiratory illnesses after their race. In fact, the non-beer runners were more than three times as likely to get sick in the weeks after the marathon than the beer drinkers were. If our team had stuck with non-alcoholic beer instead of Gatorade, we might have been able to prevent some of the late-season colds that inevitably come from running through pouring rain and ankle-deep mud in early November.
Superstitions about food may seem silly, but if you are an athlete or have one in your family, you are most likely familiar with this concept. Maybe you need to have pasta the night before a race, even though carbo-loading is only beneficial for activities lasting longer than 90 minutes. Maybe no coffee on game day. Maybe you need two biscuits with honey and three quarters of a glass of blue Powerade mixed with water. Athletes can be very specific and very serious about their rituals.
But the science shows in many cases, it doesn’t matter. Many people go with bananas as a snack before or during long races, but among cyclists, bananas provide the same benefits as a generic carbohydrate drink in terms of performance and recovery.
Nieman has found other popular foods and supplements to be ineffective. A few years ago, chia seeds – as in chia pets and heads – gained a huge boost in popularity. Many thought the seeds would help prevent disease and encourage weight loss. Even though these seeds are packed with protein and other beneficial compounds, it was not the “miracle food it was supposed to be.” Last year, Nieman and his colleagues found that the medicinal plant Rhodiola rosea did not actually live up to its claim of decreasing muscle damage after hard exercise.
Sometimes HPL studies yield a surprise: chemicals the scientists guessed would be beneficial to an athlete actually hinder their performance. For example Vitamin D2, which you can find in milk and helps build strong bones and repair muscles, damages the muscles of power athletes, the first finding of its kind.
In a more recent study, Nieman hypothesized that the unique blend of proteins and phytochemicals in pistachios would help decrease muscle damage and increase performance in cyclists, but in fact it made the cyclists move 4.8% slower in a time trial. The researchers were able to track the issue to a carbohydrate called raffinose – also found in onions, soybeans and chickpeas – that causes an immune reaction because the body cannot digest it. This immune reaction actually damages muscle cells and the cyclists move slower. Nieman, therefore, advocates avoiding those foods in the days prior to a competition.
The metabolomic work at HPL is gradually building toward a molecular understanding of the best foods to eat before competition, which can help dispel some of the myths about “miracle foods.”
Nieman, however, has found a few foods that seem to provide athletes with great benefits during and after competition. Blueberries and green tea both carry compounds called polyphenols. They take many different forms but they provide great benefits for an athlete. Nieman found that these molecules have the ability to fight off viruses. They are not powerful enough to cure the common cold but when the immune system is weak after intense exercise, the polyphenols can help prevent the common cold. They also help to reduce inflammation, which means less muscle damage and less soreness.
A word of warning, though, if you want to reap the full benefits Nieman describes in his study, you’re going to need a lot of room in the fridge. In the study, the participants consumed a concentrated powder called Nutrasorb. Their daily dose had as much polyphenol as three cups of blueberries and a cup and a half of green tea.
There is still much to learn about exactly how the foods we eat affect our bodies, but as we learn more preparing for the big game or big race can slowly move out of mysticism and towards science.
- Daniel Lane
Daniel Lane covers science, engineering, medicine and the environment in North Carolina.