Nutritional strategies can have an effect on body composition and physical performance. Intermittent fasting (IF) is an eating pattern that alternates between periods of eating and fasting for specific periods of time. In addition, it is a common strategy in athletes seeking to lose body fat. However, this strategy can negatively affect physical performance, compared to other weight loss strategies.
The results of a study have recently been published (Martínez-Rodriguez et al, 2021; Int J Environ Res Public Health 14-Jun; doi: 10.3390 / ijerph18126431) with the objective of studying the effects of high intensity interval training (HIIT), with or without intermittent fasting, on muscular and anaerobic performance in 14 physically active women (27 ± 6 years). Body composition (anthropometry), hand grip strength, and countermovement jump height (CMJ) were measured, in addition to a 30-s Wingate test.
The results showed that HIIT + IF reduced the fat mass (1 kg, p <0.05, d = 1.1; 1.5%, p <0.01, d = 1.0) and increased the height of the CMJ (6.2 cm, p <0.001, d = 1.8). Furthermore, the change in CMJ height in HIIT + IF was greater than in HIIT (5.2 cm, p <0.001, d = 1.9).
The authors suggest that intermittent fasting plus HIIT may be an effective nutritional strategy to decrease fat mass and increase jumping performance.
JL. Chicharro (PhD) Opinion:
Intermittent fasting is common in athletes who want to reduce their fat mass, but in reality, in the field of sport the main objective when using intermittent fasting is to improve performance, especially in aerobic resistance. Intermittent fasting does not necessarily establish a negative caloric balance, so it can be used without the goal of losing body fat.