Do carbohydrates actually provide the best fuel for enhancing athletic performance? Or will you be able to race even faster if you decide to restrict the amount of carbs you consume, which will force your body to draw on its stores of fat for energy? Recently that question has fuelled heated debates. Some athletes and coaches are thoroughly convinced that higher-fat, low-carb diet increase performance through training the body so that it burns through fat. Others think that large amounts of carbs are needed to make sure you have a sufficient amount in your tank in order to go fast, long and hard.
Over the last couple of years, An exercise scientific team from France and Australia have been analyzing both the pitfalls and benefits of these two philosophies. Numerous studies have show disparate results. Some have made the case for that old-school style of carb-loading, and then others have seen the benefits of low-carb plans.
Medicine & Sciences in Sports & Exercise published results from the most recent trial. It perhaps provides the clearest answers to date. As it turns out, instead of choosing one of the programs, both carbohydrate restriction and carb-loading have a role to play within your training regimen. Combining the two approaches, which includes “sleeping low” – or cutting carbs after lunch prior to a moderate-intensity workout in the morning – might increase performance. However, it is important to go about it in the right way. Otherwise, sleeping low could backfire on you.
Proof was provided by 21 competitive triathletes. They took these philosophies for a test drive for three weeks. After completing a simulated triathlon, their body fat as well as other measurements were taken. Their exercise plans and diets were commandeered by the researchers. Half of the subjects were placed on a typical training diet – lots of carbs consumed at every meal as well as following every workout – four days per week. On the other three days there were allow to eat whatever they wished to. The remaining triathletes were put on a sleep-low plan for four days per week. Their menu had the same total daily carbs that the other group’s, with the except that nearly all of the carbs were eaten at breakfast and lunch, with every few carbs after lunch.
On those days the triathletes were following the prescribed diets, all of them performed intense interval training sessions during the afternoon. This completely sapped their carbohydrate stores. The control group were able to re-up their carbs in the evening. In the meantime, the volunteers in the sleep-low group stayed depleted. Then on the next day before breakfast, everybody cycled for one hour at a moderate pace. The control athletes had their fresh supply of carbs for them to draw on for the workout. However, the sleep-group had to draw on their stores of fat for energy. Both groups then consumed a lunch rich in carbs to power up for their brutal sweat session in the afternoon.
By the time the three-week study was over, the sleep-low group was crabby. That wasn’t surprising, since their bodies at this point were starved for carbs. Their total fat mass, however, had gone down, but their lean mass remained the same – which was proof that they had been burning fat for fuel. The body fat of the control group stayed the same. Also, after all volunteers finished their second simulated triathlon, the cycling power of the subjects on the sleep-low program improved by around 12 percent and were able to run approximately 3 percent faster compared to the first trial. On the other hand, the control group ran approximately the same as on the first round.
These results show that restricting your carbs after lunch and then lightly working out the following day on low carb stores might help you decrease your time on the race. When your body is forced to burn fat without carbs, your body melts more fat, which results in you going faster.
The key thing to keep in mind is that only moderate exercise was done by the sleep-low group without having a full supply of carbs. If they had tried performing workouts that were super-intense while being depleted of carbs, their bodies would have been run ragged, as past studies have shown. The meal plan was also not followed by the triathletes every day or maintained for a long time period. Sleeping low might not be safe or effective to do over the long-term. However, if you would like to use it as part of your training program for a couple of weeks that lead up to a race you are about to run – and you are able to handle the rigidity of the plan and some hunger pains during the night – you may find yourself very pleased with your times on racing day.