Creatine Improves Total Sleep Duration Following Resistance Training Days versus Non-Resistance Training Days among Naturally Menstruating Females.
Level 2 - randomized trial
Individual double-blind randomized controlled trial
PubMed 39203908 · doi:10.3390/nu16162772
What was done
In a 6-week double-blind randomized controlled trial, 21 naturally menstruating females were randomized to receive either 5 g creatine plus 5 g maltodextrin or a placebo of 10 g maltodextrin daily. Participants performed resistance training twice weekly on an at-home gym system (TONAL). Sleep was tracked nightly using an ŌURA ring. Pre- and post-testing assessed body composition, Pittsburgh Sleep Quality Index (PSQI), dietary intake, and muscular strength.
What was found
Participants taking creatine experienced a statistically significant increase in total sleep duration on resistance training days compared to placebo (p = 0.013). No significant changes were observed for chronic sleep duration or PSQI scores between pre- and post-testing. Muscular strength scores increased over time for all participants (p < 0.001) without between-group differences. Across the cohort, dietary intake decreased significantly over time for total calories (p = 0.039), protein (p = 0.009), carbohydrates (p = 0.023), and fat (p = 0.036). Exact sleep duration numbers and effect sizes were not reported in the abstract.
Why it matters
This study provides initial evidence that creatine supplementation may selectively increase nightly sleep duration following resistance exercise in naturally menstruating females.
Limits
The sample size is very small (n = 21). Sleep was assessed with a commercial wearable device rather than polysomnography, no raw numerical data for sleep duration are provided in the abstract, and menstrual cycle phase timing was not reported.
Cited by
- supports A study in young, healthy females found that taking 5 g of creatine daily resulted in sleeping an average of 1 hour longer on training days compared to placebo.