Carbo-Loading: A Coach’s View

By Coach John Hughes

Two weeks ago Dr. Mirkin wrote a very informative article about why Carbohydrate Loading Does Not Work. His column is directed at racers. I coach regular roadies — not racers — and have a somewhat different point of view.

In the 1970s before the Davis Double Century, Roger, Steve, Gareth and I used to carbo-load. For four days we exercised and ate virtually no carbs. Because the brain can only burn carbs we were bonked and in terrible moods for the four days. Then for three days we ate lots of carbs. The night before the ride we’d eat pizza and pasta. Jim Langley may remember the Davis Double and this regimen. We couldn’t tell if carbo-loading helped but we sure hated the first four days! As Dr. Mirkin pointed out subsequent research has demonstrated that classic carbo-loading has no benefit.

I’d like to clarify a few points Dr. Mirkin makes.

“You have a tremendous amount of fat in your body but only a very limited amount of sugar [glycogen] stored in your liver and muscles. … You have only enough stored sugar to last for 12 hours at rest and 50 minutes of intense exercise.” (emphasis added).

When you are riding you are burning a combination of glucose (from carbs) and fat (even the pros have enough fat to race.) Your body can store approximately 1800 calories worth of carbohydrate as glycogen. Through endurance training you can increase your ability to store glycogen by 20 to 50%!

We’re often told not to eat much sugar; however, all carbohydrates are converted to glycogen, a type of sugar. Sugar per se isn’t bad. The Swiss Food Pyramid for Athletes recommends consuming in moderation sweets and sweetened drinks such as soft drinks, tea and energy drinks. Note that refined white sugar contains no vitamins and minerals and has no nutritional value.

“A review of 88 studies showed that eating carbohydrates during competitions lasting longer than 70 minutes will prolong your endurance far more than anything you eat before a competition.”

Eating carbs prolongs your endurance because you are replenishing your glycogen stores. Research shows that you can digest about 60 grams (240 calories) of carbs per hour of just one type of carb: e.g., glucose or sucrose (white sugar) or fructose (in fruit) or maltodextrin (in many sports nutrition products). You can digest about 90 g (360 calories) of carbs per hour if you eat two types of carbs. For example a bagel and a banana or Gatorade (sucrose) and a PowerBar (glucose and fructose). I do not recommend any specific sports nutrition products!

Research has also shown that you can rinse your mouth with a sweetened drink and rapidly spit it out so none is absorbed and still have an energy boost!

“All recent research on the subject shows that conditioned athletes can store the maximum amount of sugar in their muscles just by continuing to eat their regular diet and cutting back on the amount of training they do for three days before a competition.”(emphasis added)

This assumes that the roadie is already eating primarily carbs with limited amounts of protein and fat. Each of my clients completes a three-day nutrition log, which I review. Almost all of them consume more protein, more fat and fewer carbohydrates than recommended. Coach Dan Kehlenbach and I researched this extensively while writing our book Distance Cycling. In it we recommend that your calories come from:

• 60% from carbs (1 gm of carbs = 4 calories) Sources of carbs include fruit, vegetables and milk as well as potatoes, rice and grain products (bread, pasta, etc.)
• 15% from protein (1 gm of protein = 4 calories) Protein includes both meats and legumes.
• 25% from fats (1 gm of fat = 9 calories)

Too complicated? Your plate should be covered primarily with carbs.

The week before an event Distance Cycling recommends:

• 70-75% of total calories from carbohydrate
• 15-20% of total calories from fat
• 10% of total calories from protein

When you increase the carbs be careful not to also increase fats such as pasta sauces.

The Swiss have developed a Food Pyramid for Athletes, which you can download. Search for it on-line.

“Most athletes take their pre-race meal three to four hours before they compete.”(emphasis added)

This applies to racers. Other roadies can eat a full meal up to about 90 minutes before a ride starts.

“The meal should contain some protein in addition to carbohydrates, but avoid sugar-added drinks or foods. A pre-race meal could include eggs, oatmeal or other whole-grain cereals, oranges or other fruits, bagels and so forth.”

Good advice although having sugar in your morning coffee or tea isn’t a problem.

“You can exercise at a relaxed pace for more than three hours without needing sugar … In endurance events lasting longer than three hours, you need carbohydrates, protein, fluid and salt.”

The American College of Sports Medicine recommends consuming 25 to 60 grams of carbs (about 1 to 2 ounces or 100 to 240 calories) per hour after the first hour of exercise. Protein provides only about 5% of the energy for riding. Both protein and fat are harder to digest.

The only mineral that you need during long endurance events is salt. The food you eat will supply all of the potassium, calcium, and magnesium you need. You should eat salty foods during and after you finish long rides and races, particularly on hot days when you sweat a lot.

This is correct. Sweat is primarily salt with minimal amounts of potassium, calcium and magnesium. If you take an electrolyte supplement check that the primary ingredient is sodium.

You will recover faster by eating a high carbohydrate, high-protein meal within a half hour after finishing a race or a grueling workout. (emphasis added)

Remember that you’re burning glucose (from carbs) and fat for energy during a ride, not protein. You need protein to rebuild muscle fibers and you get enough protein in your regular diet. Nancy Clark and Jenny Hegmann in The Cyclist’s Food Guide, 2nd ed. recommend eating 0.5 gm of carbohydrate / lb. (about 1 gm. / 2 lbs) of body weight (1 gm / kg) each hour after getting off bike until you can eat a regular meal. For example, if you weigh 150 pounds, you should consume 75 gm of carbohydrate, which equals 300 calories an hour. (A 75 kg rider would also eat 75 gm of carbohydrate.) Note that you should eat this many calories per hour of carbohydrate, not just this many calories of anything. For example, I like pretzels for recovery; however, a serving totaling 300 calories has only 240 calories of carbohydrate; many energy bars are similar.

There are two kinds of roadies: those who eat to ride and those who ride to eat. I’m one of the latter and my weekly rides always include a stop for lunch.

Bon appetite!

Additional Resources:

My eArticle Eating and Drinking Like the Pros describes what and why pros eat before, during and after competition. The pros eat a lot of real food during a race, not just sports nutrition. The 15-page article includes a dozen recipes to make your own, drinks, bars, gels and other foods. Eating and Drinking Like the Pros is just $4.99.

The same principles of good nutrition for endurance apply on rides from two hours to 12 hours and beyond. All endurance riders can learn from my eArticle Eating for 100K and Beyond. It explains how to estimate how many calories you burn on rides and what you should eat on rides to avoid bonking. It compares sports bars with grocery store alternatives. It explains how to estimate your fluid and electrolyte requirements and evaluates different electrolyte supplements. Eating for 100K and Beyond is just $4.99.

 

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Coach John Hughes earned coaching certifications from USA Cycling and the National Strength and Conditioning Association. John’s cycling career includes course records in the Boston-Montreal-Boston 1200-km randonnée and the Furnace Creek 508, a Race Across AMerica (RAAM) qualifier. He has ridden solo RAAM twice and is a 5-time finisher of the 1200-km Paris-Brest-Paris. He has written over 40 eBooks and eArticles on cycling training and nutrition, available in RBR’s eBookstore at Coach John Hughes. Click to read John’s full bio.