For anyone new to endurance sports like triathlons, cycling, or running, the world of sports nutrition can seem complex. This article simplifies the essential components of an endurance athlete's diet, providing a clear plan for optimizing energy levels and achieving peak performance.
Understanding Endurance
Any aerobic exercise lasting an hour or more is considered an endurance activity. Popular examples include running, swimming, and cycling, whether in single-activity events like ultra runs or multi-sport events like triathlons. These activities demand significant energy, making proper nutrition crucial for both elite and recreational athletes.
Macronutrient Needs for Endurance Athletes
Macronutrients are the fundamental building blocks of our diet: carbohydrates, protein, and fat. Consuming these in the right ratios is essential for fueling endurance activities. While a healthy adult diet typically consists of 45-65% calories from carbs, 20-35% from fat, and 10-35% from protein, endurance athletes often need to adjust these ratios.
Carbohydrates: The Primary Fuel Source
Carbohydrates are sugars and starches that serve as the body's primary fuel, much like gasoline powers a race car. Each gram of carbohydrate provides approximately 4 calories. The body stores carbohydrates as glycogen in the muscles and liver. These glycogen reserves are vital for stabilizing blood sugar levels and enabling optimal muscle function.
Runners who consume a diet with 45-65% carbohydrates can typically store about 2 grams (8 calories) of glycogen per pound of muscle tissue, along with an additional 100-125 grams (400-500 calories) in the liver. This glycogen supply can fuel approximately 2 hours of moderate-intensity running. Therefore, supplementing with carbohydrates during longer runs is necessary to prevent glycogen depletion, which can lead to dizziness ("bonking") and severe muscle fatigue ("hitting the wall").
Read also: Carnivore Diet for Athletes
How Many Carbohydrates Do You Need?
Race Week: For races lasting longer than 3 hours, "carbo-loading" in the 72 hours before the race can enhance glycogen stores. This involves consuming 4-5 grams of easy-to-digest, low-fiber carbohydrates per pound of lean body weight each day. A shorter carbo-loading period of 48 hours may be sufficient for shorter races, especially if training volume isn't reduced pre-race.
- Easy-to-digest carbohydrate options: pretzels, plain bagels, bananas, white pasta, white rice, potato, rice-based cereals, sports drinks, and energy bars.
Race Morning: Aim for 100-150 grams of easy-to-digest, low-fiber carbohydrates in the 2-3 hours before the race. Allow 1 hour of digestion time for every 200-300 calories consumed.
- Example pre-race meal: a plain bagel with peanut butter and honey, plus 20-24 ounces of sports drink.
During Race: Consume approximately ¼-1/3 of your body weight (in pounds) in grams of carbohydrates each hour of training or racing beyond 45-90 minutes. For example, a 180-lb runner should aim for 45-60 grams of carbohydrates per hour. To optimize carbohydrate uptake and extend endurance, choose products with multiple carbohydrate types in their ingredient lists.
- Common carbohydrate sources in sports foods: maltodextrin, glucose or dextrose, sucrose, and fructose.
- Common products: sports drinks, energy gels, energy bars, and energy chews.
Post-Race: Consume 50-100 grams of carbohydrate, ideally in liquid form for rehydration and carbohydrate replenishment, as soon as possible after a hard workout or race.
Protein: Building and Repairing Muscle
Proteins are complex molecules that make up 20% of our body weight, forming muscle, bone, cartilage, skin, and other tissues. During digestion, protein breaks down into amino acids, which are used to build and repair tissues, including muscle, skin, hair, nails, and enzymes.
Read also: The Endurance Diet
Some studies suggest that including small amounts of protein during prolonged activity can improve performance by sparing muscle glycogen and aiding fluid uptake. Protein can also help reduce hunger during longer efforts. However, excessive protein intake can slow gastric emptying, leading to stomach distress and muscle fatigue or cramping.
How Much Protein Do You Need?
In Training: Endurance athletes typically need 1/2 -3/4 gram of protein per pound of lean body mass daily. Athletes on restrictive energy intakes should aim for the higher end of this range.
- Example: A 180-lb man with 10% body fat has approximately 160 lbs of lean body mass and requires 80-120 grams of protein daily.
Race Morning: Include 10-20 grams of protein in the 2-3 hours before the race to help stabilize blood sugar levels.
- Common pre-race protein sources: peanut butter, non-fat milk or yogurt, eggs, and energy bars.
During Race: For training or races longer than 4 hours, aim for up to 5 grams of protein hourly.
- Common sources: sports drinks, energy bars, turkey jerky, and peanut butter sandwiches.
Post-Race: Consuming 10-20 grams of protein immediately post-race supports muscle repair and immune function.
Read also: Keto Diet & Athletes
- Common sources: milk, meal replacement shakes, and recovery sports drinks.
Fats: Essential for Energy and Hormone Production
Endurance athletes need healthy fats in their diet, with roughly 30% of daily calories coming from fat. Dietary fat plays several crucial roles:
- Supplying energy
- Manufacturing and balancing hormones
- Forming cell membranes
- Supporting brain and nervous system function
- Transporting fat-soluble vitamins (A, D, E, and K)
- Providing essential fatty acids (linoleic and linolenic acid)
There are various types of fat, including triglycerides, fatty acids, phospholipids, and cholesterol. Endurance athletes should minimize saturated fat intake and prioritize monounsaturated fatty acids.
Healthy Fat Sources:
- Fatty fish (salmon, mackerel, tuna)
- Avocado
- Seeds (sunflower, sesame, pumpkin)
- Nuts (peanuts, walnuts, almonds, cashews)
- Olive oil
- Eggs
- Ground flaxseed
- Beans (kidney, navy, soybeans)
Micronutrients and Fluid Intake
In addition to macronutrients, certain micronutrients and adequate fluid intake are crucial for endurance athletes.
Electrolytes: Maintaining Fluid Balance and Muscle Function
Electrolyte replacement is essential for endurance activities lasting longer than 1 hour, especially in hot and humid conditions. Key electrolytes include sodium, potassium, magnesium, and calcium, which are involved in metabolic activities and essential for normal cell function, including muscle function. Electrolyte imbalances can cause symptoms similar to dehydration, such as nausea, vomiting, muscle weakness, cramping, fatigue, labored breathing, tingling, and confusion.
How Many Electrolytes Do You Need?
- Pre-Race: Athletes prone to muscle cramping and fatigue, or those competing in hot weather, may benefit from increasing salt intake in the days leading up to the race. Carbo-loading options like pretzels, sports drinks, breads, and cereals can help with this. On race morning, choosing saltier carbohydrate sources like a salt bagel and sipping on a sports drink may also be beneficial. (Note: Salt loading is not recommended for those on blood pressure medications.)
- During Race: Aim for 200-500 mg of sodium per 20-24 ounces of water consumed, along with smaller amounts of potassium, magnesium, and calcium. Be mindful of sodium intake from all sources, including sports drinks (100-200 mg per 8 oz), energy gels (25-200 mg per packet), chews (20-210 mg per 3 pieces), salt packets (~200 mg per packet), and electrolyte capsules (~100-200 mg per capsule). Excessive sodium can lead to bloating and GI discomfort.
- Post-Race: Sipping on a sports drink post-race facilitates optimal rehydration and electrolyte replacement.
Water: The Foundation of Performance
Water is essential for all metabolic activity, lubricating muscles and joints, and regulating body temperature. Dehydration can significantly impair health and performance. Determining sweat rate and fluid needs is crucial for endurance athletes. Weighing in before and after workouts and drinking fluids to minimize body weight loss (no more than 2%) during training and racing is recommended.
How Much Water Do You Need to Drink?
- Daily: Drink half your body weight (in pounds) in fluid ounces, or aim for pale yellow urine throughout the day. For example, a 150-lb man requires approximately 75 ounces of fluid daily.
- Pre-Race: Sip on 16-24 ounces of fluid in the 1-2 hours leading up to the race, ensuring urine is pale yellow.
- During-Race: Aim for ½-1 liter (approximately 20-24 ounces) per hour, or adjust intake to maintain pale yellow urine. Over-hydration (hyponatremia) can be as dangerous as dehydration, often caused by excessive fluid consumption, especially water. Symptoms include clear urine, pressure headaches, nausea, vomiting, and confusion. Monitor hydration status by weighing in pre- and post-workout, aiming to stay within 2% of pre-workout weight.
- Post-Race: If you've lost more than 2% of your pre-workout weight, sip on fluids until urine is pale yellow again. Approximately 20 ounces of fluid are needed to replenish 1 lb of body weight.
Nutrient Timing for Optimal Endurance Performance
Achieving peak performance requires strategically timing nutrient intake before, during, and after training and events.
- Before Endurance Training: Consume 1 gram of carbohydrate per kilogram of body weight 2 hours prior and 20 ounces of water 2 hours before starting.
- During Endurance Training: Consume 10 ounces of fluid with electrolytes and a 5% carbohydrate concentration every 20 minutes.
- After Endurance Training: Consume 1.5 grams of carbohydrate per kg of body weight and 15 to 25 grams of protein within the first 30 minutes post-exercise, along with 24 ounces of water for every pound of body weight lost.
Extra Credit: Caffeine
Caffeine, a central nervous system stimulant, can help maintain blood glucose concentration and reduce perceived exertion. Aim for 100-300 mg of caffeine (e.g., 1-3 cups of coffee) in the 2-3 hours before the race and another 25-50 mg hourly during the later stages. Avoid consuming more than 500 mg of caffeine on race day. Consider eliminating caffeine for 10 days before racing for best results.
Challenging Common Nutrition Beliefs
If you're exercising vigorously for more than an hour a day, it may be beneficial to rethink some conventional nutrition wisdom.
- Avoid Refined Carbs and Added Sugar: While complex carbs are generally recommended, refined carbs consumed in moderation and at the right time can help athletes quickly replenish energy levels.
- Limit Carbs Altogether: Low-carb diets may hinder metabolism, decrease athletic performance, and lead to long-term weight gain and injuries.
- Avoid High-Fat, Calorie-Dense Foods: Elite athletes need more calories overall, and high-fat, calorie-dense foods can help meet these needs. Don't restrict calories when exercising a lot.
- Never Eat Between Meals: Highly active individuals need to eat every three to four hours, with some athletes eating five to seven times per day.
- Don’t Eat Before Bed: A small bit of protein before bed may aid in muscle recovery.
- Reduce Salt Intake: If you're sweating a lot, you may need extra salt in your diet to prevent cramps and dehydration.
- Eat Only Whole Foods, Not Supplements: While whole foods are essential, some supplements, like protein, vitamin D, iron, and omega-3 fatty acids, may be helpful for athletes.
- Plant-Based Milk Is Better Than Cow’s Milk: Plant-based milks often contain less fat, protein, and carbs than whole milk, which are crucial for supporting athletic performance.
Maintaining a Healthy Relationship with Food
Food should be both healthful and pleasurable. Monitor your appetite, provide energy to your body, and eat mindfully. Avoid pre-packaged convenience foods and prepare meals at home more frequently.
Sample 7-Day Meal Plan for Athletes
This 7-day meal plan provides an example of a 2,300 kcal diet, based on 50% carbohydrates, 25% fat, and 25% protein. This specific plan is designed for a moderately active female, but individual needs may vary.
Day One
- Breakfast: English Muffin with Peanut Butter & Apples, Soy Milk
- Snack 1: Greek Yogurt and Pear
- Lunch: Chickpea Wrap with Baby Carrots
- Snack 2: Popcorn, pumpkin seeds, dried cherries, and an orange
- Dinner: Turkey and Cheese Meatball sub with Parmesan Broccoli
Day Two
- Breakfast: Chicken sausage and sweet potato hash
- Lunch: Chicken pita with an orange, cheese and crackers
- Afternoon Snack: English muffin with cottage cheese, fruit and baby carrots
- Dinner: High protein jerk chicken breast with quinoa, lime cucumber salad
Day Three
- Breakfast: PB banana toast with blackberries
- Snack 1: almonds and tangerines
- Lunch: Chicken, brown rice and salad with banana and PB
- Snack 2: apple with string cheese
- Dinner: Baked Chicken and veggies with spaghetti and honey roasted brussel sprouts
Day Seven
- Breakfast: Eggs and Turkey Sausage, Apple
- Lunch: Chicken, Pretzels, Snap Peas, and Fruit, Pear, Trail Mix & Yogurt
- Pre-workout: English Muffin with Strawberry Jelly
- Post workout Dinner: Simple Chicken Burger with Blueberries, Simple Brussels Sprouts