Some athletes that have been coached to eat a high carbohydrate diet prior to competition are afraid of changing their diet even one iota. Thinking of going on a ketogenic diet may be too much of a stretch for them to consider.
What Started The High Carb Craze for Athletes
The high carbohydrate diet for athletes started around 1960. That’s when scientists found out that when the glycogen stores in the muscles were depleted, athletes developed fatigue. By eating more carbohydrate foods, the muscle glycogen levels were maintained and the athletes could better perform.
This was what led to the big spaghetti or pizza meals prior to competition, and the variety of high carbohydrate drinks on the market for athletes to replenish their body’s needs.
But all that may be different now that additional physiological research has been done. Here’s a list of a few of the results of the studies:
- High Carb Could Make an Athlete Diabetic
High carbohydrate meals – especially with foods high on the glycemic index scale – can and will also raise insulin levels much higher than normal. When this happens, then over time insulin resistance and even diabetes may occur. There’s also a rebound of blood sugar that then dips down into the low blood sugar zone a few hours after a high carbohydrate meal is eaten.
- No Real Need for Carbs
The body actually doesn’t need any carbohydrates to survive. It can survive adequately on only protein and fat. Thus, carbohydrate foods are simply extra foods the body really doesn’t need. Since this is true for humans, it’s also true for athletes.
- Humans Can Burn Fat Without Carbohydrates
Humans adapt to starvation by switching metabolism to fat-burning, and the switch occurs quite elegantly in the body. After a few weeks, the body’s ketone levels increase dramatically for the purpose of replacing glucose as the primary source of energy for the brain. The fatty acids give the muscles the energy they need. Protein breakdown also allows extra energy to be generated.
- Cyclists Did Better With A Ketogenic Diet
Consumption of a ketogenic diet with less than 10 grams of carbohydrates a day for four weeks did not compromise endurance performance in elite cyclists in one study, according to the researchers.
They found that over 90% of their fuel for the sporting event came from fat burning. These athletes were exercising at 64% maximal oxygen consumption, a high rate indeed. (Even highly trained athletes may never reach 64% maximal oxygen consumption.)
In a multi-university study of 20 elite ultra-marathoners and Ironman distance triathletes, scientists instructed one group to eat a high carbohydrate diet while another group consumed a very low carbohydrate diet (ketogenic). They did this for an average of 20 months.
Then the scientists tested the peak fat oxidation of both groups. The higher the fat oxidation rates, the better the group would be breaking down fat and using it for energy. The peak fat oxidation was 2.3 times higher in the group on the ketogenic diet.
Simultaneously, the VO2 max (the ability of the body to use oxygen during maximal exercise) was at 70.3 for the ketogenic group compared to only 54.9 for the high carb group. Both types of athletes used muscle glycogen similarly and replenished it similarly.
This showed the scientists that runners could get better athletic performance from their body when eating a ketogenic diet.
Should you eat a ketogenic diet? No one can tell you yes or no. You simply have to try it out for yourself.
Source: Volek, Jeff S., et al. Metabolic characteristics of keto-adapted ultra-endurance runners. Metabolism Clin and Exptl 65, 2016, p 100-110. http://www.metabolismjournal.com/article/S0026-0495(15)00334-0/pdf