Endurance athlete nutrition is a very interesting topic that seems to evolve every decade or so, often in fad-ish ways, sometimes in ways that truly seem to offer up something valuable for athletes pushing themselves to extreme limits. Most trends die out because they are hard to sustain and/or they have negative health consequences over the long run. Probably the newest idea taking hold is that it has become very common in the world of endurance sports for athletes to try to consume 100 grams (400 calories) or more of carbohydrates per hour during training and racing. The thinking goes, if you can consume it you can burn it and this is true. The caloric demands of high level mountain biking are very high – a racer can easily burn 600-1,000 calories per hour. A 4 hour hard training ride can burn all the calories you eat that day. The promise is intriguing for what this means in long endurance events. Over the course of hours of training and racing the less we have to dig into our stores of glycogen the better. The reality is that it is very hard to consume carbohydrates at this rate and the athletes that do have to consume highly processed and sugary drink powders, gels, and chews to achieve this. Most mountain bike racing is a little different. Races tend to be no longer than 2.5-3 hours and are often much shorter. The quality and quantity of food consumed before the race is much more important than consuming as much carbohydrate as possible during the race. This is good news for your GI health and your oral health. There is a dark side to consuming extreme levels of carbohydrates like this during endurance events. It is very hard on your gut, your teeth, and your brain. Treat any type of sugar that is not found in a piece of fruit like an addictive drug which is what it is. Spiking your sugar intake like this is not good for your long term health and bodes poorly for longevity in the sport. The long term studies of extreme carbohydrate loading during intense exercise are not well understood yet, but already many experts in the field of nutrition and sports physiology are predicting that the current crop of pro athletes in events like the grand tours or Iron Mans will have shorter careers than their predecessors.
Let’s focus first on general diet and caloric needs. The high level mountain biker needs to have a diet very low in added sugar, processed foods, and minimal or no alcohol. The bulk of their diet needs to come from natural, unprocessed food sources. Their caloric needs will be much higher than the average person, consuming upwards of 3-4,000 calories a day is common. On rest days the athlete may consider 16 hour fasting, that is, only eating between 10:00 and 6:00 in order to rest their digestive systems as well. Caloric needs will correspondingly be much lower on rest days. Their diet does not need to follow strict rules but should follow some general principles. Approximately 60% of calories should be carbohydrates, about 20% should be protein, and about 20% should be fat. If the athlete is getting these calories from natural, unprocessed food sources this should provide them with the micro nutrients they need as well. The bulk of carbohydrates should come from whole grains such as quinoa, millet, rice, and oats, high quality bread or pasta, and potatoes. Fiber is a complex carbohydrate and the high level athlete would do well to include lots of sources of fiber in their diet. Hydrophilic (water retaining) sources of fiber such as chia seeds, flax seeds, and psyllium husk are great sources of energy, plus they help keep water in the gut for hydration, and trap and remove waste in the digestive system. Good sources of protein are wild caught salmon, free range chicken, lentils, and eggs. The masters athlete over 40 should be especially mindful of protein requirements. Good sources of fat are nuts and nut butters, avocados, whole milk dairy products (also a good source of protein), and olive oil. Saturated fat should be no more than a quarter of total fat consumed. Any and all fruits and vegetables should be eaten in high quantities. Again, these are guidelines, not rules.
Hydration very much depends on the individual and the climate. With humidity and heat the body needs more water. Most of the water that an athlete consumes should be just that, water. Moderate amounts of coffee are beneficial to many athletes. Herbal tea can be consumed in high quantities. Juices and powdered drinks should be avoided, they are processed and high in sugar. Read the ingredient list carefully with oat, soy, nut, coconut, or other non dairy milks. Some are fine, some are highly processed and filled with sugar. General rule of thumb is drink lots of water throughout the day until 2 hours before bed time to avoid sleep disruption caused by frequent night time urination.
Pre and post-race fueling, hydration, and fueling during a race are more complex. Often nervousness and stress make it harder to eat and can cause GI problems. The dinner the night before and breakfast morning of the race can be hard meals to get down. Experience helps calm things down but if the jitters are affecting you here are some strategies that can help. Don’t go out to a restaurant for these meals, prepare yourself things you are used to eating that you like. Avoid spices and avoid greasy foods. Eat slowly to try to consume more calories while making it easier for your gut to digest. Give yourself at least half an hour to an hour to digest breakfast before you begin your warmup for the race. Focus on eating lots of complex carbs for breakfast, a meal high in fat and protein can make you feel heavy and sluggish. Try eating a couple rice cakes or half a banana after warming up before heading to the start line. During racing hydrate often when not descending. Aim for at least a liter of water per hour. Instead of sugary powders try diluted coconut water with a pinch of salt. If your race is less than an hour and a half you probably don’t need to eat during the race. For races longer than that try applesauce in a pouch instead of energy gel. Instead of energy bars try a little nice bread with avocado or peanut butter. After your race begin refueling as soon as you can handle getting some food in your system. Carbs are usually easier to tolerate at first, but protein and fat should follow as soon as possible, as should salt. Drink lots of water in the hours following a race.
Long training rides and races are not an excuse to eat ‘energy’ food. Yes, you need to snack a lot during difficult, long rides and races. Yes, ‘energy’ foods are wrapped in convenient packaging that makes them easy to consume while riding. Try granola sweetened with dates, peanut butter sandwiches, baby carrots, rice cakes, bananas or apples, and almonds. Slice an apple ahead of time and put it in a little sandwich bag. Cut a sandwich into little bite sized cubes. It isn’t complicated. Energy food is junk food. Period. Bars, gels, powders, and chews are highly processed, filled with sugar, and are bad for your digestive and oral health. Diarrhea, cavities and sugar spikes do not need to be a part of endurance sports. Energy food won’t kill you but there are better, cheaper, healthier options.
Vitamins and supplements are a loaded subject for many athletes. In general the claims they make should be regarded with suspicion. It’s easy to think that popping a multivitamin could plug nutritional holes if we are lacking micro nutrients. However the endurance athlete on a high calorie diet filled with varied, nutritious, unprocessed foods probably isn’t lacking any micro nutrients, and the problem with vitamins or fortified foods is that those same nutrients tend to pass right through our systems rather than being absorbed when we eat them in unprocessed foods. While a vitamin is unlikely to hurt you it is not a fix for a sub-optimal diet. Supplements are an even touchier subject. It is possible that some supplements may have some health benefits. Things like fish oil, creatine, or collagen support healthy tissues and cell growth but can also be found in real foods. Ashwagandha and valerian root have been used for millennia to stimulate focus or encourage sleep. Some supplements are age old traditional medicines. Again, be skeptical of supplement claims, and know that the difference between a supplement and a medication is lack of thorough scientific study and FDA support. The standards for calling something a health supplement are not very high. Just like with vitamins a sub-optimal diet cannot be fixed with supplements. Consult with a nutritionist and your doctor if you have dietary concerns.
There isn’t one right way to fuel your body as a mountain bike athlete. If you focus on frequent hydration and getting enough calories of nutritious, unprocessed foods high in fruits, vegetables, whole grains, nuts, high quality dairy products, and lean meats, and cutting out added sugars, alcohol, and processed foods you are likely doing fine. If you have dietary restrictions such as gluten sensitivity, or follow a vegetarian or vegan diet you will have to figure out ways to eat enough of the macro and micro nutrients you need, but there are many examples of great athletes who have done just that. If still in doubt consult with a medical expert.