None listed
Conditions
Brief summary
Sleep improves the health, well-being and performance of individuals undergoing training, so this study aims to investigate a practical nutritional aid in attempt to improve sleep quality. The impact of diet on sleep is a growing area of research interest, with reports that protein intakes high in tryptophan may benefit sleep, especially for those experiencing sleep complaints. In addition to sleep, the intake of alpha-lactalbumin may improve mood and cognitive performance of an individual. The proposed mechanism by which sleep, mood and cognition are affected is through increases in tryptophan availability to the brain, which can be measured through blood plasma concentrations. The effect of alpha-lactalbumin intake on these measures has not been completed within a trained population with sleep difficulties. Therefore, we are testing the hypotheses that alpha-lactalbumin supplementation in the evening will improve sleep characteristics, mood, and cognitive performance of trained individuals 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 five 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 m
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 five 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 - 3 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 the sleep, mood, and cognition of a trained population with sleep difficulties compared to placebo. Amino acid analysis and melatonin measured within blood plasma to explore potential mechanisms by which alpha-lactalbumin may influence sleep 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. As participants will complete the intervention periods at the Deakin University campus, a member of the research team (or research assistant) will be providing both the supplement and meals to the participants. This means adherence to both the diet and supplement is able to be observed. 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 will be mixed up and matched for taste by an external researcher, to ensure both participants and the researcher 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
Inclusion: Participants must be between 18-40 years old, and currently be completing structured moderate-vigorous 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 (Appendix 1) and Pittsburgh Sleep Quality Index (Appendix 2), 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. Female participants are required to be naturally menstruating or taking an oral contraceptive pill. As female hormone differences across the menstrual cycle can influence sleep, participation will occur during predictable phases where the influence of hormones is low.
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