None listed
Conditions
Brief summary
Sleep is important for the optimal health and performance of an athlete. Data suggests that as sleep debt accumulates, sports-related performance is further reduced. Athletes with sleep difficulties are prone to accumulating sleep debt and are therefore of greater risk of impaired performance. This athlete cohort need sleep intervention, with recent research indicating diet influences an athlete’s sleep. Protein supplements high in the amino acid tryptophan may promote sleep through increases in melatonin, with individuals experiencing sleep difficulties believed to be more receptive to the sleep-promoting benefits of tryptophan. Therefore, this study aims to investigate the effect of a potentially sleep-promoting protein supplement (alpha-lactalbumin) on the sleep and performance of athletes with sleep difficulties.
Interventions
Study design - Randomised, double-blinded, counterbalanced, crossover design
(Crossover experimental group = 40 g alpha-lactalbumin; Crossover placebo group = 40 g collagen)
As a cross-over trial, to limit any potential carry over effects of the alpha-lactalbumin into the next intervention period, a minimum six-night washout period is to be observed. Further, to ensure the influence of female hormones is low throughout the intervention periods (as this can confound sleep outcomes), naturally me
Study design - Randomised, double-blinded, counterbalanced, crossover design (Crossover experimental group = 40 g alpha-lactalbumin; Crossover placebo group = 40 g collagen) As a cross-over trial, to limit any potential carry over effects of the alpha-lactalbumin into the next intervention period, a minimum six-night washout period is to be observed. Further, to ensure the influence of female hormones is low throughout the intervention periods (as this can confound sleep outcomes), naturally menstruating females are to complete both intervention periods during the early follicular phase. This phase will be determined through menses and menstrual cycle mapping. Experimental group - alpha-lactalbumin Product - BiPRO Alpha 9000 (Agropur Inc, Appleton, WI) Dose - 40 grams once daily Duration - 7 days Dosage form - Powder, oral Route of Administration - Oral Active ingredient - Tryptophan (1.9 g) To investigate the effect of evening supplementation (2 hours prior to sleep) of 40 g alpha-lactalbumin for seven nights on the sleep, mood, recovery, and sports-related performance of athletes with sleep difficulties compared to placebo. Sports-related performance measures will be completed on multiple occasions. Performance measures will be tested the day immediately following seven days of supplementation (alpha-lactalbumin and placebo), and the day following the six-day washout period to observe any “legacy” effect of alpha-lactalbumin supplementation on performance. These sports-related performance tests will be completed at the Deakin University Burwood campus. To control for protein's potential confounding influence on the effectiveness of alpha-lactalbumin supplementation, participants diet will be standardised to meet habitual energy intake, and 1.2 g/kg of body weight of daily protein. This amount is at the lowest end of recommended protein amounts for athletes. Participants will complete the intervention periods within their habitual environments. Supplements and meals will be provided to participants in advance by a member of the research team. Adherence to supplement and meal consumption will be monitored through reporting in a dietary software app. Further, all meals (3 main meals + 2 snacks) will be provided by a member of the research team, with participants able to consume additional low-protein snacks if they wish to do so (must be replicated by the participant for both intervention periods). The dietary supplement (alpha-lactalbumin or placebo) will be prepared and matched for taste by an external researcher to ensure both participants and the research team remain blind to the treatments.
Sponsors
Deakin University
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
Participants must be between 18-40 years old, and actively competing in a team-sport and registered with a club at a minimum community level. Participants will be recruited from a range of invasion team-sports (e.g., football, rugby, soccer) with participants to be completing structured exercise at least three times per week for a minimum total of five hours per week to meet “trained athlete” guidelines. Further, participants will be screened using the Athlete Sleep Screening Questionnaire and Pittsburgh Sleep Quality Index, and those with a sleep difficulty score equal to or greater than 5, global PSQI score >5 and a sleep onset latency >15 minutes will be eligible. These scores coincide with equal to or greater than mild sleep difficulty and poor-quality sleep, which are the targeted participants for this study.
Exclusion criteria
Exclusion: smoking, excessive alcohol consumption (>17 standard drinks per week), dairy allergy, high caffeine use (e.g., >5 mg·kg-1·d-1), antidepressant or sleep medication use, current or recently finished night shift work, recent transmeridian travel, fluctuating bedtimes, and pregnancy. These exclusions criteria relate to confounding influences that may affect sleep or the plasma TRP:LNAA ratio.
Outcome results
None listed