Macronutrients: The Skinny on Carbohydrates, Fats and Proteins

Forget carb-loading. Most endurance athletes consume too many carbs and are dependent on that source of energy for their training and racing. For better performance, athletes would be better off carb-unloading.

Athletes who cut back on carbs are able to become more efficient at burning fat for fuel, which improves endurance and performance. The first step is to stop eating carbs alone and instead, combine them with protein and fat.

The calories you consume on a daily basis come from the three primary macronutrients: carbohydrates, fats and proteins. Each nutrient has a different molecular makeup, different digestion and absorption pathways and play specific roles in the body. Carbohydrates provide quick energy and fuel the brain. Protein delivers the building blocks needed to rebuild muscle. Fat protects the body and has an anti-inflammatory effect.

You need all three. But what amount of each is ideal? It differs from person to person depending on body composition goals, activity level and metabolism.

More: The Art of Carbo-Loading

Carbohydrate

Types: Monosaccharides, disaccharides, oligosaccharides, polysaccharides
Sources of body carb: Blood glucose, glycogen (storage in muscle/liver)
Food options: Grains, vegetables, fruits, legumes, baked goods and dairy products
Best choices: Fruits, vegetables and legumes
Performance-related roles in the body:

  • Fuels your body during high-intensity exercise
  • Preserves tissue proteins
  • Primes fat breakdown for fuel
  • Provides fuel to the brain

Protein

Types: Essential amino acids (not made in the body) and non-essential amino acids (made in the body)
Sources of body protein: Blood plasma, visceral tissue, muscle (65 percent) -- No storage reservoirs.
Food options: Meats, seafood, dairy, eggs and plant-based proteins such as peanuts, beans, tofu, almonds and chickpeas.
Best choices: All are good. Focus on lean proteins and moderate amounts of dairy.
Performance-related roles in the body:

  • Major building blocks for tissues (metabolic, hormonal, genetic, growth roles)
  • Neutralizes excess acid produced during training
  • Activates vitamins

More: High-Protein Foods for Optimal Recovery

Fat

Types: Simple lipids (triglycerides), compound lipids (HDL/LDL), derived lipids (cholesterol)
Sources of body fat: 90 percent found in adipose tissue
Food options: Oils, animal proteins, dairy products, butter, eggs, processed/packaged junk foods
Best choices: A combination of unsaturated and saturated fatty-acid foods
Unsaturated: Nuts, seeds, olive oil, canola oil, fish
Saturated: Animal meats, dairy products, egg yolks, coconut oil
Performance-related roles in the body:

  • Fuels your body during lower-intensity workouts, spares glycogen and protein
  • Protects vital organs
  • Thermally insulates the body
  • Omega 3's reduce inflammation

Recipe Ideas

Consuming carbs alone, or in large amounts relative to fat and protein, leads to erratic blood sugar and inconsistent energy levels. Keep energy steady by including fats and proteins with carbs. Here are some great breakfast, lunch and dinner meal ideas:
  • Egg scramble with tomatoes, black beans and avocado
  • Plain Greek yogurt with mixed berries and walnuts
  • Ni?oise salad (albacore tuna, kalamata olives, green beans, roasted potatoes, vinaigrette)
  • Chicken salad (cranberries, Veganaise, sliced almonds, black sesame seeds and mixed greens)
  • Grilled salmon with sweet potato and kale salad
  • Beef filet with baked potato, butter and broccoli

The ideal percentages consumed are individual and require some trial and error to find the right formula. Speak to your doctor for a detailed look at what your body needs.

More: Good vs. Bad Fats and the Effect on Your Body

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About the Author

Brooke Schohl

Brooke is a registered sports dietitian and the owner of Fuel to the Finish Endurance Nutrition Coaching/Destination Kona Triathlon Store in Scottsdale, Arizona. She is an avid triathlete, having recently completed her third Ironman. She integrates that personal experience and knowledge into developing customized, sport-specific fueling plans for her clients.

Brooke is a registered sports dietitian and the owner of Fuel to the Finish Endurance Nutrition Coaching/Destination Kona Triathlon Store in Scottsdale, Arizona. She is an avid triathlete, having recently completed her third Ironman. She integrates that personal experience and knowledge into developing customized, sport-specific fueling plans for her clients.

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