Carb loading is a common ritual among endurance athletes for pre-race preparation; however a new study suggests eating rice, pasta and oatmeal might not be the best method after all.  A new study published in the journal Nutrients, led by Hiroaki Tanaka, Ph.D., claims carbs are important, but misunderstood when it comes to eating on race day.

Based on the hypothesis of Hiroaki Tanaka and his team, they hypothesized that high fat consumption would jump-start fat metabolism during exercise, thereby preserving the body’s carbohydrate stores for use later during a race or long run.

How they came up with their conclusion

The researchers had eight male collegiate distance runners carb-load for three days with minimal exercise in order to maximize glycogen storage. Four hours before a treadmill test, the athletes were randomly served either a high-fat meal (1000 calories of 30 percent carbs, 55 percent fat and 15 percent protein) or a high-carb meal (1000 calories of 70 percent carbs, 21 percent fat and 9 percent protein). Just before the test they took a placebo, which is an easily digestible carb commonly found in sports drink and gels.  The placebo replaced the carbs used in the four hours between the meal and the treadmill test.

Each athlete then ran 80 minutes at marathon pace and then at their highest speed thereafter.  Once running was complete, blood samples were taken and gas exchange measured to monitor fat versus carbohydrate metabolism.  The study consisted of three trials with a week separation between tests.

The final conclusion of the study revealed that the athletes who ate a high-fat meal and the carb jelly increased their endurance on average  by 10 minutes—that is, they sustained the faster segment after the 80-minute warm-up longer. Time to exhaustion for runners who ate the high-fat meal but the placebo jelly was not statistically relevant, but all but one runner prolonged endurance by two to eight minutes.

According to this study fats are good pre-race day with subsequent ingestion of carbs, which many athletes will find very pleasing.  This study is very interesting and intriguing. I might just have that extra scoop of almond butter on my next run. What are your thoughts and opinions on this study?

I must also note that the study suggests that high-fat meals are only effective if your carb stores are full. The study cites improper carbo-loading as one key reason several previous studies concluded that high-fat pre-race meals did not extend endurance. Adequate digestion time is also important.

To learn more about this study it can be found at