Sports Medicine and Fitness

Biography

Biography: Shengyan Sun

Abstract

This study aims to compare the effects of 4 weeks of ketogenic diet (KD) and combined exercise training on body composition and cardiometabolic health outcomes. Forty-nine overweight females (age: 20.9 ± 3.1 years, BMI: 25.3 ± 2.9 kg/m²) were randomly assigned to KD control group (KD-CON, n=17), KD and high-intensity interval training group (KD-HIIT, n=19), or KD and moderate-intensity continuous training group (KD-MICT, n=13), all subjects consumed KD during the study period. KD-HIIT and KD-MICT received extra training 5 d/week for 4 weeks (KD-HIIT: 10 × 6-s cycling interspersed with 9-s rest, MICT: 30-min continuous cycling at 50-60% V̇O_2peak). After intervention, all three groups demonstrated significant reductions in body weight (-3.2 kg in KD-CON, -2.7 kg in KD-HIIT, -2.6 kg in KD-MICT, p < 0.001, ²= 0.801), body fat percentage (-2.3% in KD-CON, -3.1% in KD-HIIT, -2.8% in KD-MICT, p < 0.001, ²= 0.704), BMI (p < 0.001, ²= 0.816) and waist-to-hip ratio (p < 0.001, ²= 0.507). V̇O_2peak was improved by 10.7% in KD-HIIT and 11.8% in KD-MICT, but remained unchanged in KD-CON. Circulating levels of high-density lipoprotein, low density lipoprotein and cholesterol were increased in all three groups, whereas glucose and triglyceride were unchanged. In summary, the short-term KD is an effective and rapid approach to improve body composition in overweight females, but caution is required when use it for long-term as it may elevate blood lipids. Combined exercise training has additional benefits on cardiovascular fitness, but HIIT is more time efficient than MICT (2.5-min vs. 30-min).