Research shows during the first six months of dieting, a low-carb diet is more effective than a low-fat or mixed diets.
For this reason, some people decided to follow low-carb diets to fuel their training sessions. But this is not the right approach.
A number of studies carried out since the 1960s has undoubtedly shown that carbs are the primary fuel for exercise at intensities above 65% of maximum effort. Endurance decreases significantly during low-carb dieting, especially during repeated training sessions.
A Brazilian study found out that a low-carb diet decreased high-intensity exercise capacity and endurance in physically active men. Researchers measured exercise capacity in maximum watts, or the power one produces during training—the more power you’re producing, the harder you are working.
However, the perception of effort wasn’t different between high- and low-carb diets. To say it differently, one doesn’t feel any worse during exercise on low-carb diets but can’t work as hard.
So, eat your carbs if you want to train hard. However, you don’t have to exaggerate because there’s no difference in performance when training on high-carb intake and higher-carb intake, according to a Scottish study.