Effects of Ketogenic Diet on Body Composition and Performance in Soccer Players

Effects of a Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, Metabolism and Performance in Semi-professional Soccer Players

A ketogenic diet (KD) is a nutritional approach, usually adopted for weight loss, that restricts daily carbohydrates under 30 g/day. KD showed contradictory results on sport performance, whilst no data are available on team sports. The investigators will investigate the influence of a KD on different parameters in soccer players

Sixteen semi-professional soccer players will be randomly assigned to a ketogenic diet (KD n=8) or to a western diet (WD n=8). Diets contain the same amount of protein (1.8g/Kg body weight/day). Body weight and body composition will be measured by dual energy x-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). Resting energy expenditure (REE), respiratory exchange ratio (RER), cross sectional area (CSA) and isometric muscle strength of quadriceps, counter movement jump (CMJ) and yoyo intermittent recovery test will be measured.

Inclusion Criteria

• semiprofessional soccer players
• male

Exclusion Criteria:

• body fat percentage over 32%, (determined via dual energy X-ray absorptiometry DEXA),
• cardiovascular,
• respiratory, gastrointestinal,
• thyroid or any other metabolic diseases,
• weight change more than 2 Kg over the last month,
• adherence to special diets,
• use of nutritional supplements (except a daily multivitamin-mineral)
• use of medication to control blood lipids or glucose and goal-keepers.