Bite Size Tip #2: Full Stomach, Empty Legs: The ‘Too Clean’ Paradox for Endurance Athletes


Gillian is a competitive road cyclist. She’s adamant on getting her nutrition from whole foods, predominantly fruits and vegetables, some grains, healthy fats and lean proteins. Processed anything is currently a big NO in her mind. She’s struggling, though, and finds herself unable to repeat her high intensity intervals and is fading halfway into three-hour rides. She’s often tired, bloated and lacking stamina. She knows something has to change for her performance and energy to improve.

Gillian surfs the net and Dr. Google tells her she needs to eat more carbohydrates. She heads to the grocery store and buys more broccoli, cantaloupes, peppers and nourishing produce. At dinner her salad becomes enormous. Gillian is now full all of the time and tells her coach she’s “always eating,” so they assume her energy depletion can’t be caused by her nutrition. After further consultation on her nutrition, however, she is surprised to discover her energy needs are not being met, particularly her carbohydrates needs.

Gillian is pounding out big training weeks of at least 15 hours, but she’s only consuming 5g/kg body weight of carbohydrates on training days (at 63.6kg (140 lbs), 5g/kg equates to 318g of carbohydrates). She’s doing well with her optimal protein and fat intake. It’s recommended that her intake be closer to 7 to 9g/kg during her high training load weeks, depending on the work load for the day.

Once the problem has been determined, Gillian discovers it’s easily managed. Her carbohydrate choices are nutrient dense, meaning they have good nutrient content; however, they are also high-volume foods with low-energy density, meaning they don’t have a lot of calories. Gillian is eating often, but the bowls of broccoli, peppers, yogurt dip and cantaloupe aren’t high enough in carbohydrates.

After learning more about high-energy density carbohydrates and the benefits of simple sugars pre, during and post ride for easy digestion, Gillian makes some changes:

Current carbohydrate intake 5g/kg

  • 5 cups of broccoli per day 23g carbohydrates
  • 2 cups quinoa cooked 78g carbohydrates
  • 2 medium bell peppers 14g carbohydrates
  • 1 cup steal cut oats cooked 36g carbohydrates
  • 6 cups spinach 7g carbohydrates
  • 1 sweet potato 31g carbohydrates
  • 1 small cantaloupe 36g carbohydrates
  • 1 medium apple 25g carbohydrates
  • 1 cup brown rice cooked 51g carbohydrates
  • 4 medium carrots 23g carbohydrates
  • TOTAL: 326g carbohydrates

Revised Carbohydrate intake at 8g/kg body weight

  • 3 cups of broccoli 14g carbohydrates
  • 2 cups quinoa cooked 78g carbohydrates
  • 1 medium bell peppers 7g carbohydrates
  • 1 cup steal cut oats cooked 36g carbohydrates
  • 6 cups spinach 7g carbohydrates
  • 1 sweet potato 31g carbohydrates
  • 1 cup grapes 27g carbohydrates
  • 1 medium apple 25g carbohydrates
  • 2 cup brown rice cooked 102g carbohydrates
  • 4 medjool dates 72g carbohydrates
  • 1 banana 27g carbohydrates
  • 1.5 tbsp maple syrup 20g carbohydrates
  • 1 bagel + 1 tbsp honey 70g carbohydrates
  • TOTAL carbohydrate 8g/kg approx 515g

Gillian added approximately 200g of carbohydrates, without increasing her fiber intake.  She’s now consuming a low fat and fiber snack before training and spreads her carbohydrate intake out throughout the day. This includes a sports drink and other easy to digest carbohydrates while training, based on duration and intensity. Gillian notices quickly that her top end repeatability, stamina and energy for her non-training hours improves.

This case study is based on a mock athlete. While everyone’s situation is different, many athletes like Gillian exist. Because they feel full, these athletes genuinely believe they are meeting their energy and carbohydrate needs. Often these athletes can benefit from adding energy dense foods, including home baked goods to bring on rides, while removing some higher fiber foods or changing their timing of intake around training. Context is everything when it comes to nutrition food types and timing.

You invest so much time into your training. Make a point to investigate your nutrition to optimize both your training and health. A healthy fed athlete is a consistent athlete.

Join the Prokit Community
Create an account to follow your favorite athletes, experts and topics
Have an account? Sign In
Profile Photo

Anne Guzman

Sport scientist, sports nutritionist, content creator, former pro cyclist, life long learner. “Find a way to your dreams, even if it involves detours."
Running, Cycling, Triathlon, Track Cycling, Wrestling
Hamilton, ON

More from Anne Guzman …