Dataset Information

Time-restricted eating effects on performance, immune function, and body composition in elite cyclists: a randomized controlled trial

ABSTRACT:

Background

Although there is substantial interest in intermittent fasting as a dietary approach in active individuals, information regarding its effects in elite endurance athletes is currently unavailable. The present parallel randomized trial investigated the effects of a particular intermittent fasting approach, called time-restricted eating (TRE), during 4?weeks of high-level endurance training.

Methods

Sixteen elite under-23 cyclists were randomly assigned either to a TRE group or a control group (ND). The TRE group consumed 100% of its estimated daily energy needs in an 8-h time window (from 10:00?a.m. to 6:00?p.m.) whilst energy intake in the ND group was distributed in 3 meals consumed between 7:00?a.m. and 9:00?p.m. Fat and fat-free mass were estimated by bioelectrical impedance analysis and VO2max and basal metabolism by indirect gas analyzer. In addition, blood counts, anabolic hormones (i.e. free testosterone, IGF-1) and inflammatory markers (i.e. IL-6, TNF-?) were assessed.

Results

TRE reduced body weight (??2%; p?=?0.04) and fat mass percentage (??1.1%; p?=?0.01) with no change in fat-free mass. Performance tests showed no significant differences between groups, however the peak power output/body weight ratio (PPO/BW) improved in TRE group due to weight loss (p?=?0.02). Free testosterone and IGF-1 decreased significantly (p?=?0.01 and p?=?0.03 respectively) in TRE group. Leucocyte count decreased in ND group (p?=?0.02) whilst the neutrophils-to-lymphocytes ratio (NLR) decreased significantly (p?=?0.03) in TRE group.

Conclusions

Our results suggest that a TRE program with an 8-h feeding window elicits weight loss, improves body composition and increases PPO/BW in elite cyclists. TRE could also be beneficial for reducing inflammation and may have a protective effect on some components of the immune system. Overall, TRE could be considered as a component of a periodized nutrition plan in endurance athletes.

Trial registration

This trial was retrospectively registered at clinicaltrials.gov as NCT04320784 on 25 March 2020.

SUBMITTER: Moro T

PROVIDER: S-EPMC7733258 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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