Introduction and objective:
Restrictive diets are growing in popularity as more athletes attempt to improve their physical performance. One such diet that has recently attracted interest is the ketogenic diet, which drastically restricts carbohydrate intake to fewer than 20g per day. The primary objective of this diet is to induce a metabolic state called ketosis, which results in the production of ketone bodies and allows the body to primarily rely on fat as a source of energy. The purpose of this study was to investigate the effects of a ketogenic diet on athletic performance.

Brief description of the state of knowledge:
The reported reduction in body weight and body fat remained unaffected by weightlifting performance. Maximal aerobic performance remained unaltered. Running performance over 5 km and endurance during CrossFit training showed no significant differences. During the Wingate test, the ketogenic diet decreased average and peak power by 6% and 7%, respectively. The total distance run in the yo-yo intermittent recovery test was 15% less after the ketogenic diet.

According to a review of studies, there is no conclusive evidence that a ketogenic diet improves athletic performance. Despite the fact that this diet can aid in weight loss in weight-class sports, it can have a negative impact on performance in activities requiring high levels of sustained effort. There is no conclusive evidence that following a ketogenic diet leads to significant improvements in athletic performance.

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