The interactive effect of sustained sleep restriction and resistance exercise on skeletal muscle transcriptomics in young females.

Both sleep loss and exercise regulate gene expression in skeletal muscle, yet little is known about how the interaction of these stressors affects the transcriptome. The aim of this study was to investigate the effect of nine nights of sleep restriction (SR), with repeated resistance exercise (REx) sessions, on the skeletal muscle transcriptome of young, trained females. Ten healthy females aged 18-35 yr old undertook a randomized cross-over study of nine nights of SR (5 h time in bed) and normal sleep (NS; ≥7 h time in bed) with a minimum 6-wk washout. Participants completed four REx sessions per condition (days 3, 5, 7, and 9). Muscle biopsies were collected both pre- and post-REx on days 3 and 9. Gene and protein expression were assessed by RNA sequencing and Western blot, respectively. Three or nine nights of SR had no effect on the muscle transcriptome independently of exercise. However, close to 3,000 transcripts were differentially regulated (false discovery rate < 0.05) 48 h after the completion of three resistance exercise sessions in both NS and SR conditions. Only 39% of downregulated genes and 18% of upregulated genes were common between both conditions, indicating a moderating effect of SR on the response to exercise. SR and REx interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested.NEW & NOTEWORTHY This study investigated the effect of nine nights of sleep restriction, with repeated resistance exercise sessions, on the skeletal muscle transcriptome of young, trained females. Sleep restriction and resistance exercise interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested.

Sustained Sleep Restriction Reduces Resistance Exercise Quality and Quantity in Females.

INTRODUCTION: Female athletes sleep less and report more sleep problems than their male counterparts. Inadequate sleep reduces maximal strength in male athletes; however, little is known about the impact of sleep restriction (SR) on the quantity and quality of resistance exercise performed by female athletes. This study investigated the effect of nine nights of moderate SR on repeated resistance exercise performance, hormonal responses, and perceived fatigue in females. METHODS: Ten healthy, resistance-trained, eumenorrheic females age 18-35 yr underwent nine nights of SR (5-h time in bed) and normal sleep (NS; ≥7-h time in bed) in a randomized, crossover fashion with a minimum 6-wk washout. Participants completed four resistance exercise sessions per trial, with blood samples collected before and after exercise. Exercise performance was assessed using volume load, reactive strength index, and mean concentric velocity with rating of perceived exertion recorded after exercise. Participants completed awakening saliva sampling and the Multi-component Training Distress Scale daily. RESULTS: Volume load decreased trivially (<1%, P < 0.05) with SR. Mean concentric velocity per set was slower during SR for the lower-body (up to 15%, P < 0.05), but not the upper-body, compound lifts. Intraset velocity loss was up to 7% greater during SR for back squats ( P < 0.05). SR increased salivary cortisol area under the curve (by 42%), total training distress (by 84%), and session perceived exertion (by 11%). CONCLUSIONS: Sustained SR reduces markers of resistance exercise quality (bar velocity) more than quantity (volume load) and increases perceived effort at the same relative intensity in resistance-trained females. Markers of exercise quality and internal load may be more sensitive than volume load, to advise coaches to the decline in lifting performance for female athletes experiencing SR.

Resistance Training and Skeletal Muscle Protein Metabolism in Eumenorrheic Females: Implications for Researchers and Practitioners.

Resistance training is essential for health and performance and confers many benefits such as increasing skeletal muscle mass, increasing strength and power output, and improving metabolic health. Resistance training is a major component of the physical activity guidelines, yet research in female populations is limited. Recent increases in the promotion of, and the participation by, females in sport and exercise, highlight the need for an increase in understanding of evidence-based best practice exercise prescription for females. The aim of this review is to provide an overview of the current research regarding resistance training performance and skeletal muscle adaptation in females, with a focus on the hormonal variables that may influence resistance training outcomes. Findings suggest that the menstrual cycle phase may impact strength, but not skeletal muscle protein metabolism. In comparison, oral contraception use in females may reduce skeletal muscle protein synthesis, but not strength outcomes, when compared to non-users. Future research should investigate the role of resistance training in the maintenance of skeletal muscle protein metabolism during pregnancy, menopause and in athletes experiencing relative energy deficiency in sport. The review concludes with recommendations for researchers to assist them in the inclusion of female participants in resistance training research specifically, with commentary on the most appropriate methods of controlling for, or understanding the implications of, hormonal fluctuations. For practitioners, the current evidence suggests possible resistance training practices that could optimise performance outcomes in females, although further research is warranted.

Inadequate sleep and muscle strength: Implications for resistance training.

OBJECTIVES: Inadequate sleep (e.g., an insufficient duration of sleep per night) can reduce physical performance and has been linked to adverse metabolic health outcomes. Resistance exercise is an effective means to maintain and improve physical capacity and metabolic health, however, the outcomes for populations who may perform resistance exercise during periods of inadequate sleep are unknown. The primary aim of this systematic review was to evaluate the effect of sleep deprivation (i.e. no sleep) and sleep restriction (i.e. a reduced sleep duration) on resistance exercise performance. A secondary aim was to explore the effects on hormonal indicators or markers of muscle protein metabolism. METHODS: A systematic search of five electronic databases was conducted with terms related to three combined concepts: inadequate sleep; resistance exercise; performance and physiological outcomes. Study quality and biases were assessed using the Effective Public Health Practice Project quality assessment tool. RESULTS: Seventeen studies met the inclusion criteria and were rated as 'moderate' or 'weak' for global quality. Sleep deprivation had little effect on muscle strength during resistance exercise. In contrast, consecutive nights of sleep restriction could reduce the force output of multi-joint, but not single-joint movements. Results were conflicting regarding hormonal responses to resistance training. CONCLUSION: Inadequate sleep impairs maximal muscle strength in compound movements when performed without specific interventions designed to increase motivation. Strategies to assist groups facing inadequate sleep to effectively perform resistance training may include supplementing their motivation by training in groups or ingesting caffeine; or training prior to prolonged periods of wakefulness.