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Cited by 186Sleep and related disordersCircadian rhythm and melatoninSleep and Work-Related Fatigue

Sleep and Nutrition Interactions: Implications for Athletes

Open access
Doherty, Rónán, Madigan, Sharon, Warrington, Giles, Ellis, Jason·2019·Nutrients
DOI 10.3390/nu11040822PMC PMC6520871
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Abstract

This narrative review explores the relationship between sleep and nutrition. Various nutritional interventions have been shown to improve sleep including high carbohydrate, high glycaemic index evening meals, melatonin, tryptophan rich protein, tart cherry juice, kiwifruit and micronutrients. Sleep disturbances and short sleep duration are behavioural risk factors for inflammation, associated with increased risk of illness and disease, which can be modified to promote sleep health. For sleep to have a restorative effect on the body, it must be of adequate duration and quality; particularly for athletes whose physical and mental recovery needs may be greater due to the high physiological and psychological demands placed on them during training and competition. Sleep has been shown to have a restorative effect on the immune system, the endocrine system, facilitate the recovery of the nervous system and metabolic cost of the waking state and has an integral role in learning, memory and synaptic plasticity, all of which can impact both athletic recovery and performance. Functional food-based interventions designed to enhance sleep quality and quantity or promote general health, sleep health, training adaptations and/or recovery warrant further investigation.

AI snapshot

Written from the paper’s full text.

TL;DR

This narrative review examines interactions between sleep and nutrition, with a focus on implications for athlete recovery and performance. It concludes that several nutritional interventions may improve sleep, but evidence in athletic populations remains limited and requires further investigation.

Key findings

  • Nutritional factors reported to affect sleep include high-carbohydrate/high-glycaemic-index evening meals, melatonin, tryptophan-rich protein, tart cherry juice, kiwifruit, and micronutrients such as B vitamins and magnesium.
  • A high-GI meal consumed four hours before bed significantly reduced sleep onset latency (9.0 ± 6.2 min) compared with a low-GI meal (17.5 ± 6.2 min) and the same meal consumed one hour before bed (14.6 ± 9.9 min; p = 0.009).
  • Tart cherry juice supplementation increased time in bed (+24 min), total sleep duration (+34 min), sleep efficiency (82.3%), and reduced daytime napping (–22%) (p < 0.05); in older females with insomnia (n = 7), it reduced insomnia severity index scores and wake after sleep onset.
  • In athletes, sleep disturbances are common: professional male ice hockey players (n = 23) had mean total sleep duration of 6.92 h (95% CI 6.3–7.5 h), and 66% of elite German athletes (n = 632) reported pre-competition insomnia symptoms; sleep duration <8 h was the strongest predictor of injury in adolescent athletes (RR = 2.1; 95% CI 1.2–3.9).

Methods

  • Narrative review; no systematic search strategy, inclusion/exclusion criteria, or meta-analytic synthesis is described.
  • Synthesizes existing literature on sleep physiology, sleep in athletes, and nutritional interventions including carbohydrate, melatonin, tryptophan-rich protein, antioxidants, tart cherry, kiwifruit, B vitamins, and magnesium.
  • Draws on studies with varied designs and populations, including athletes (e.g., n = 23 ice hockey players; n = 632 German athletes), healthy adults, older adults, and some animal evidence.

Limitations

  • The paper states that further research is warranted, particularly in athletic populations, and that the effects of tryptophan-rich protein interventions, antioxidant recovery-promoting doses, and food-based sleep interventions require more investigation.
  • The paper notes that the kiwifruit study lacked a control group, had a high dropout rate (n = 5), and recruited subjects interested in a dietary sleep intervention, which may bias findings.
  • Evident from the text: as a narrative review, it lacks systematic quality appraisal; conclusions rely on heterogeneous studies, several small samples (e.g., n = 6, n = 7, n = 14, n = 25, n = 43), and some animal or mechanistic evidence, so causality and generalizability to athletes are not established.

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Integrity signals

Registry

Crossref · 10.3390/nu11040822

Cites

72 of 72 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 142 cited sources checked · 0 supported · 0 flagged

  • Premisenone given

    Various nutritional interventions improve sleep, including high carbohydrate, high glycaemic index evening meals, melatonin, tryptophan rich protein, tart cherry juice, kiwifruit and micronutrients.

    “Various nutritional interventions have been shown to improve sleep including high carbohydrate, high glycaemic index evening meals, melatonin, tryptophan rich protein, tart cherry juice, kiwifruit and micronutrients.”
    Quote in the paperNot a substantial claim
  • Premisecitation

    For sleep to have a restorative effect on the body, it must be of adequate duration and quality.

    “For sleep to have a restorative effect on the body, it must be of adequate duration and quality; particularly for athletes whose physical and mental recovery needs may be greater due to the high physiological and psychological demands placed on them during training and competition.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [28] Samuels, 2016, The Athlete Sleep Screening Questionnaire: A new tool for assessing and managing sleep in elite athletes, Br. J. Sports Med. source

      Not checked in the free run.

    • cites [42] Hirshkowitz, 2015, National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary, Sleep Health source

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  • Premisecitation

    A high glycaemic index evening meal reduces sleep onset latency.

    “Nutrients such as carbohydrate (high glycaemic index evening meal reduced sleep onset latency)”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [37] Jeukendrup, 2017, Periodized Nutrition for Athletes, Sports Med. source

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    • cites [44] Afaghi, 2007, High-glycemic-index carbohydrate meals shorten sleep onset, Am. J. Clin. Nutr. source

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  • Premisecitation

    Inadequate recovery can reduce autonomic nervous system resources, with an associated reduction in heart rate variability and increased resting heart rate.

    “Inadequate recovery can reduce autonomic nervous system (ANS) resources, with an associated reduction in heart rate variability (HRV) and increased resting heart rate [30].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] Hynynen, 2006, Heart rate variability during night sleep and after awakening in overtrained athletes, Med. Sci. Sports Exerc. source

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  • Premisecitation

    Process C can be modified by exogenous cues.

    “Give that Process C can be modified by exogenous cues [27], there is scope for investigation of nutrition interventions to enhance sleep quality and quantity.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [27] Johnston, 2014, Physiological links between circadian rhythms, metabolism and nutrition, Exp. Physiol. source

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  • Classified as probably not a substantial claim. 10

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    Premisecitation

    Sleep disturbances and short sleep duration are behavioural risk factors for inflammation and are associated with increased risk of illness and disease.

    “Sleep disturbances and short sleep duration are behavioural risk factors for inflammation, associated with increased risk of illness and disease, which can be modified to promote sleep health.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [18] Irwin, 2016, Sleep disturbance, sleep duration, and inflammation: A systematic review and meta-analysis of cohort studies and experimental sleep deprivation, Biol. Psychiatry source

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    • cites [42] Hirshkowitz, 2015, National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary, Sleep Health source

      Not checked in the free run.

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    Premisecitation

    Sleep has a restorative effect on the immune system, the endocrine system, facilitates recovery of the nervous system and metabolic cost of the waking state, and has an integral role in learning, memory and synaptic plasticity.

    “Sleep has been shown to have a restorative effect on the immune system, the endocrine system, facilitate the recovery of the nervous system and metabolic cost of the waking state and has an integral role in learning, memory and synaptic plasticity, all of which can impact both athletic recovery and performance.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [18] Irwin, 2016, Sleep disturbance, sleep duration, and inflammation: A systematic review and meta-analysis of cohort studies and experimental sleep deprivation, Biol. Psychiatry source

      Not checked in the free run.

    • cites [19] Frank, 2006, The mystery of sleep function: Current perspectives and future directions, Rev. Neurosci. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Caffeine consumption can lead to poor sleep which, in turn, can lead to increased caffeine consumption.

    “Caffeine consumption can lead to poor sleep which, in turn, can lead to increased caffeine consumption.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Premisecitation

    Nutrition support needs to be periodised in relation to the demands of the athlete's daily training and overall nutritional goals.

    “Nutrition support needs to be periodised in relation to the demands of the athlete’s daily training and overall nutritional goals [36].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [36] Thomas, 2016, American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance, Med. Sci. Sports Exerc.

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    Premisecitation

    Sleep deprivation adversely affects glucose metabolism and neuroendocrine function, which can affect carbohydrate metabolism, appetite, energy intake and protein synthesis.

    “Sleep deprivation adversely affects glucose metabolism and neuroendocrine function which can affect carbohydrate metabolism, appetite, energy intake and protein synthesis [1].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Halson, 2014, Sleep in elite athletes and nutritional interventions to enhance sleep, Sports Med. source

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    Premisecitation

    Training adaptations and recovery can be maximised by optimal nutrition practices or impaired by suboptimal nutrition practices.

    “Training adaptations and recovery can be maximised by optimal nutrition practices or impaired by suboptimal nutrition practices [36,37,38].”
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    • cites [36] Thomas, 2016, American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance, Med. Sci. Sports Exerc.

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    • cites [37] Jeukendrup, 2017, Periodized Nutrition for Athletes, Sports Med. source

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    • cites [38] Close, 2016, New strategies in sport nutrition to increase exercise performance, Free Radic. Biol. Med. source

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    Premisecitation

    Long sleep duration (>8 h per night) was associated with increased IL-6 (ES: 0.11 (0.02-0.20)) and increased CRP (ES: 0.17 (0.01-0.34)).

    “Short sleep duration (< 7 h per night) was associated with increased IL-6 (ES: 0.29 (0.05–0.52)), while long sleep duration (> 8 h per night) was also associated with increased IL-6 (ES: 0.11 (0.02–0.20)) but also increased CRP (ES: 0.17 (0.01–0.34)) [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] Irwin, 2016, Sleep disturbance, sleep duration, and inflammation: A systematic review and meta-analysis of cohort studies and experimental sleep deprivation, Biol. Psychiatry source

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    Premisecitation

    Sleep has a pivotal role in performance, training adaptations and recovery.

    “Sleep also has a pivotal role to play in performance, training adaptations and recovery [1,18].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [1] Halson, 2014, Sleep in elite athletes and nutritional interventions to enhance sleep, Sports Med. source

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    • cites [18] Irwin, 2016, Sleep disturbance, sleep duration, and inflammation: A systematic review and meta-analysis of cohort studies and experimental sleep deprivation, Biol. Psychiatry source

      Not checked in the free run.

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    Premisecitation

    Sleep disturbance and extremes of sleep duration affect risk factors of inflammatory disease and contribute to all-cause mortality.

    “Research has demonstrated that sleep disturbance (i.e. insomnia) and extremes of sleep durations affect risk factors of inflammatory disease and contribute to all-cause mortality [18,22].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [18] Irwin, 2016, Sleep disturbance, sleep duration, and inflammation: A systematic review and meta-analysis of cohort studies and experimental sleep deprivation, Biol. Psychiatry source

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    • cites [22] Vgontzas, 2013, Insomnia with objective short sleep duration: The most biologically severe phenotype of the disorder, Sleep Med. Rev. source

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    Premisecitation

    Caffeine increases sleep onset latency, reduces total sleep duration and reduces sleep quality.

    “caffeine (increased sleep onset latency, reduced total sleep duration and reduced sleep quality) [39]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [39] Tahara, 2014, Chrono-biology, Chrono-pharmacology and Chrono-nutrition, J. Pharmacol. Sci. source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The classic view of sleep is that it is a recovery process, with the circadian system regulating feelings of sleepiness and wakefulness throughout the day.

    “The classic view of sleep is that it is a recovery process, with the circadian system regulating feelings of sleepiness and wakefulness throughout the day [28].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [28] Samuels, 2016, The Athlete Sleep Screening Questionnaire: A new tool for assessing and managing sleep in elite athletes, Br. J. Sports Med. source

      Not checked in the free run.

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    Premisecitation

    The focus of 'training' nutrition is to promote adaptations while the focus of 'competition' nutrition is optimal performance.

    “The focus of ‘training’ nutrition is to promote adaptations while the focus of ‘competition’ nutrition is optimal performance [36].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [36] Thomas, 2016, American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance, Med. Sci. Sports Exerc.

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    Premisecitation

    Sleep disturbances and inadequate sleep duration have been reported in athletic populations.

    “Sleep disturbances and inadequate sleep duration have been reported in athletic populations.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [32] Tuomilehto, 2017, Sleep of professional athletes: Underexploited potential to improve health and performance, J. Sports Sci. source

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    • cites [33] Erlacher, 2011, Sleep habits in German athletes before important competitions or games, J. Sports Sci. source

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    • cites [15] Venter, 2012, Role of sleep in performance and recovery of athletes: A review article, South Afr. J. Res. Sport Phys. Educ. Recreat.

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    Premisecitation

    A meta-analysis of sleep duration and all-cause mortality demonstrated a U-shaped association: long sleep (>8 h per night) has a 30% greater risk (RR: 1.30 (1.22-1.38)) and short sleep (<7 h per night) has a 12% greater risk (RR: 1.12 (1.06-1.18)) compared to normal sleep (7-8 h per night).

    “Similarly, a meta-analysis of sleep duration and all-cause mortality demonstrated a U-shaped association, whereby long sleep (> 8 h per night) has a 30% (RR: 1.30 (1.22–1.38)) greater risk while short sleep (<7 h per night) has a 12% (RR: 1.12 (1.06–1.18)) greater risk compared to normal sleep reference (7–8 h per night) [25].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [25] Cappuccio, 2010, Sleep duration and all-cause mortality: A systematic review and meta-analysis of prospective studies, Sleep source

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    Premisecitation

    The relationship between sleep, performance and recovery can be viewed in terms of three key factors: sleep length, sleep quality and sleep phase.

    “The relationship between sleep, performance and recovery can be viewed in terms of 3 key factors that affect the recuperative outcome: Sleep length (total sleep duration; hours/night, plus naps)Sleep quality (i.e., the experience and perceived adequacy of sleep)Sleep phase (circadian timing of sleep) [28].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [28] Samuels, 2016, The Athlete Sleep Screening Questionnaire: A new tool for assessing and managing sleep in elite athletes, Br. J. Sports Med. source

      Not checked in the free run.

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    Premisecitation

    66% (n = 416) of elite German athletes (n = 632) reported pre-competition insomnia symptomology including difficulty falling asleep, waking during the night and early final waking times.

    “While a similar study found that 66% (n = 416) of elite German athletes (n = 632) reported pre-competition insomnia symptomology including difficulty falling asleep, waking during the night and early final waking times [33].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [33] Erlacher, 2011, Sleep habits in German athletes before important competitions or games, J. Sports Sci. source

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    Premisecitation

    Large portions and/or meals later in the evening can negatively impact sleep, potentially due to the thermogenic effect of digestion.

    “large portions and/or meals later in the evening can negatively impact sleep potentially due to the thermogenic effect of digestion) can affect circadian rhythms [40].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

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    Premisecitation

    Caffeine increases alertness by antagonising adenosine receptors, which leads to a reduction in the inclination to sleep.

    “Caffeine increases the state of alertness, antagonising adenosine receptors, which also leads to a reduction in the inclination to sleep [39].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [39] Tahara, 2014, Chrono-biology, Chrono-pharmacology and Chrono-nutrition, J. Pharmacol. Sci. source

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    Premisecitation

    Muscle fatigue or soreness may adversely affect sleep, with inflammatory cytokines linked to disruption of normal sleep.

    “Muscle fatigue or soreness may adversely affect sleep, with inflammatory cytokines linked to disruption of normal sleep [29].”
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    • cites [29] Hausswirth, 2014, Evidence of disturbed sleep and increased illness in overreached endurance athletes, Med. Sci. Sports Exerc. source

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    Premisecitation

    Sleep deprivation is associated with increased catabolic and reduced anabolic hormones, which results in impaired muscle protein synthesis, blunting training adaptations and recovery.

    “Sleep deprivation is associated with increased catabolic and reduced anabolic hormones which results in impaired muscle protein synthesis [31], blunting training adaptations and recovery.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [31] Dattilo, 2011, Sleep and muscle recovery: Endocrinological and molecular basis for a new and promising hypothesis, Med. Hypotheses source

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    Premisecitation

    Alcohol consumption is associated with poorer sleep quality and quantity, reduced REM sleep and increased sleep disturbance in the second half of the sleep bout.

    “Alcohol consumption has been associated with poorer sleep quality and quantity, reduced REM sleep and increased sleep disturbance in the second half of the sleep bout [41].”
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    • cites [41] Roehrs, 2001, Sleep, sleepiness, and alcohol use, Alcohol. Res. Health

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    Premisecitation

    Tryptophan is an essential amino acid that is a precursor to serotonin and melatonin, and can cross the blood-brain barrier by competing for transport with other LNAA.

    “Tryptophan is an essential amino acid that is a precursor to serotonin and melatonin, which can cross the blood-brain barrier by competing for transport with other LNAA [1].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Halson, 2014, Sleep in elite athletes and nutritional interventions to enhance sleep, Sports Med. source

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    Premisecitation

    Insulin influences the transport of tryptophan across the blood brain barrier after a carbohydrate rich meal and facilitates the uptake of LNAA by muscle.

    “Insulin influences the transport of tryptophan across the blood brain barrier after a carbohydrate rich meal, as it is an anabolic agent it also facilitates the uptake of LNAA by muscle [26].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [26] Golem, 2014, An integrative review of sleep for nutrition professionals, Adv. Nutr. source

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    Premisecitation

    Sleep disturbances and sleep deprivation are risk factors for inflammation, which can be treated or managed to promote recovery and/or performance.

    “Similar to nutrition, sleep disturbances (difficulty initiating or maintain sleep) and sleep deprivation (not getting enough sleep) are risk factors for inflammation [18,42], which can be treated or managed to promote recovery and/or performance.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [18] Irwin, 2016, Sleep disturbance, sleep duration, and inflammation: A systematic review and meta-analysis of cohort studies and experimental sleep deprivation, Biol. Psychiatry source

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    • cites [42] Hirshkowitz, 2015, National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary, Sleep Health source

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    Interpretationcitation

    Since endogenous melatonin influences core temperature facilitating sleep, increased exogenous melatonin could affect changes in core temperature improving sleep quality.

    “Since endogenous melatonin influences core temperature facilitating sleep, increased exogenous melatonin could affect changes in core temperature improving sleep quality [50].”
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    • cites [50] Howatson, 2012, Effect of tart cherry juice (Prunus Cerasus) on melatonin levels and enhanced sleep quality, Eur. J. Nutr. source

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    • Rests on an assumption: The effect of exogenous melatonin on sleep quality is relative to the person’s endogenous melatonin levels.

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    Premisecitation

    For sleep to have a restorative effect, it must be of adequate duration, which is dependent on age.

    “For sleep to have a restorative effect on the body, it must be of adequate duration which is dependent on age [28,42].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [28] Samuels, 2016, The Athlete Sleep Screening Questionnaire: A new tool for assessing and managing sleep in elite athletes, Br. J. Sports Med. source

      Not checked in the free run.

    • cites [42] Hirshkowitz, 2015, National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary, Sleep Health source

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    Premisecitation

    Melatonin is a naturally-occurring compound in cow's milk, but its concentration increases significantly if cows are milked in darkness at night, referred to as 'night time milk'.

    “Melatonin is a naturally-occurring compound in cow’s milk, but its concentration increases significantly if cows are milked in darkness at night referred to as ‘night time milk’ [40].”
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    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

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    Premisecitation

    The ratio of tryptophan:LNAA in the blood is vital to the transport of tryptophan into the brain and can be increased through consumption of tryptophan, a high carbohydrate/low protein diet or α-lactalbumin.

    “The ratio of tryptophan:LNAA in the blood is vital to the transport of tryptophan into the brain and can be increased through consumption of tryptophan, a high carbohydrate/low protein diet or α-lactalbumin (whey derived protein) [43].”
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    • cites [43] Silber, 2010, Effects of tryptophan loading on human cognition, mood, and sleep, Neurosci. Biobehav. Rev. source

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    Premisecitation

    Ingestion of melatonin affects sleep propensity and has hypnotic effects enhancing sleep quality and duration; pharmacological melatonin can be used to manipulate circadian timing.

    “Ingestion of melatonin affects sleep propensity and has hypnotic effects enhancing sleep quality and duration, pharmacological melatonin can be used to manipulate circadian timing [49].”
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    • cites [49] Collin, 2010, Melatonin: Action as antioxidant and potential applications in human disease and aging, Toxicology source

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    Premisecitation

    A dose response relationship for melatonin was not evident, as the 0.3 mg dose was as effective as the 1 mg dose when administered at 6:00 pm or 8:00 pm.

    “A dose response relationship was not evident as the 0.3 mg dose, which is similar to endogenous melatonin concentrations, was as effective as the 1 mg dose when administered at 6:00 pm or 8:00 pm.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [52] Pires, 2001, Acute effects of low doses of melatonin on the sleep of young healthy subjects, J. Pineal Res. source

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    Premisecitation

    Melatonin is a hormone secreted by the pineal gland that has sedative effects.

    “Melatonin is a hormone secreted by the pineal gland, that has displayed sedative effects [48,49].”
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    • cites [48] Ramis, 2015, Protective effects of melatonin and mitochondria-targeted antioxidants against oxidative stress: A review, Curr. Med. Chem. source

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    • cites [49] Collin, 2010, Melatonin: Action as antioxidant and potential applications in human disease and aging, Toxicology source

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    Premisecitation

    The impact of melatonin on sleep onset latency was time dependent: a 0.3 mg dose increased sleep onset latency when consumed at 9:00 pm, and there was no evidence of an effect when the 1 mg dose was administered at 9:00 pm.

    “However, the impact was time dependent as a 0.3 mg dose increased sleep onset latency when consumed at 9:00 pm (0.3 mg 25.1 ± 10.5 min; 1 mg 12.1 ± 7.4 min; Placebo 8.8 ± 4 min) and there was no evidence of an effect when the 1 mg dose was administered at 9:00 pm [52].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [52] Pires, 2001, Acute effects of low doses of melatonin on the sleep of young healthy subjects, J. Pineal Res. source

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    Premisecitation

    Carbohydrates affect plasma tryptophan:LNAA ratio and may complement the sleep enhancing effect of consuming tryptophan rich protein.

    “Carbohydrates affect plasma tryptophan:LNAA ratio and may compliment the sleep enhancing effect of consuming tryptophan rich protein [40].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Sleep recommendations change over the lifespan: adolescents 8-10 h, adults 7-9 h, and older adults 7-8 h.

    “Sleep recommendations particularly the amount of sleep required, change over the lifespan from adolescents (8–10 h), adults (7–9 h), and older adults (7–8 h) [42].”
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    • cites [42] Hirshkowitz, 2015, National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary, Sleep Health source

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    Premisecitation

    The internal clock can be altered by changing the timing and nature of food intake.

    “It has been suggested that the internal clock can be altered by changing the timing and nature of food intake [39].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [39] Tahara, 2014, Chrono-biology, Chrono-pharmacology and Chrono-nutrition, J. Pharmacol. Sci. source

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    Premisecitation

    Conversion to serotonin is dependent on sufficient precursor availability in the brain; an increase in brain tryptophan occurs when the ratio of free tryptophan to branched chain amino acids increases; following tryptophan conversion to serotonin, melatonin is produced.

    “Conversion to serotonin is dependent on sufficient precursor availability in the brain, an increase in brain tryptophan occurs when the ratio of free tryptophan to branched chain amino acids increases, following tryptophan conversion to serotonin, melatonin is produced [1].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] Halson, 2014, Sleep in elite athletes and nutritional interventions to enhance sleep, Sports Med. source

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    Premisecitation

    Melatonin has extremely low toxicity even at relatively high doses and can easily cross physiological barriers due to its optimal size, partial water solubility and high lipid solubility.

    “Melatonin has extremely low toxicity even at relatively high doses and can easily cross physiological barriers due to its optimal size, partial water solubility and high lipid solubility however, it must be noted that there appears to be no added benefit to doses >3 mg [49].”
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    • cites [49] Collin, 2010, Melatonin: Action as antioxidant and potential applications in human disease and aging, Toxicology source

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    Premisecitation

    Supplementation with high doses (800 IU/day) of vitamin E did not counteract oxidative stress in triathletes (n = 38); the intervention group demonstrated significantly (p ≤ 0.05) higher levels of post-race inflammation and oxidative stress (Plasma F2-isoprostanes increased 181% versus 97% and IL-6 166 ± 28 pg∙mL-1 versus 88 ± 13 pg∙mL-1) than the control group.

    “However, supplementation with high doses (800 IU/day) of vitamin E did not counteract OS in triathletes (n = 38), the intervention group demonstrated significantly (p ≤ 0.05) higher levels of post-race inflammation and OS (Plasma F2-isoprostanes increased 181% versus 97% and IL-6 166 ± 28 pg∙mL–1 versus 88 ± 13 pg∙mL–1) than the control group [60].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [60] Nieman, 2004, Vitamin E and immunity after the Kona triathlon world championship, Med. Sci. Sports Exerc. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    During recovery, athletes can suffer from delayed onset muscle soreness (DOMS), which can reduce sleep quantity and quality.

    “During recovery athletes can suffer from delayed onset muscle soreness (DOMS) [66], which can reduce sleep quantity and quality.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [66] Bell, P., Stevenson, E., Davison, G., and Howatson, G. (2016). The effects of Montmorency tart cherry concentrate supplementation on recovery following prolonged, intermittent exercise. Nutrients, 8. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Tart cherries contain high concentrations of melatonin and a range of phenolic compounds with antioxidant and anti-inflammatory properties.

    “Tart cherries contain high concentrations of melatonin and a range of phenolic compounds that have both antioxidant and anti-inflammatory properties [66,67].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [66] Bell, P., Stevenson, E., Davison, G., and Howatson, G. (2016). The effects of Montmorency tart cherry concentrate supplementation on recovery following prolonged, intermittent exercise. Nutrients, 8. source

      Not checked in the free run.

    • cites [67] Howatson, 2010, Influence of tart cherry juice on indices of recovery following marathon running, Scan. J. Med. Sci. Sports source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Vitamin E is an important antioxidant due to its abundance within cells, mitochondrial membranes and its ability to act directly on reactive oxygen species.

    “Vitamin E is an important antioxidant due to its abundance within cells, mitochondrial membranes and its ability to act directly on reactive oxygen species [60].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [60] Nieman, 2004, Vitamin E and immunity after the Kona triathlon world championship, Med. Sci. Sports Exerc. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Vitamin E reacts with other antioxidants such as vitamin C, beta-carotene and lipoic acid, which have the capacity to regenerate vitamin E from its oxidised form.

    “Vitamin E reacts with other antioxidants such as vitamin C, beta-carotene and lipoic acid, which have the capacity to regenerate vitamin E from its oxidised form.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [60] Nieman, 2004, Vitamin E and immunity after the Kona triathlon world championship, Med. Sci. Sports Exerc. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In the intervention group, tart cherry juice supplementation significantly elevated total melatonin content, increased time in bed (+24 min), increased total sleep duration (+34 min), improved sleep efficiency (82.3%), and reduced daytime napping (-22%) (p < 0.05).

    “In the intervention group tart cherry juice supplementation resulted in significantly elevated total melatonin content, increased time in bed (+24 min), increased total sleep duration (+34 min) improved sleep efficiency total (82.3%) and a significant reduction in daytime napping (–22%) (p < 0.05) [50].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [50] Howatson, 2012, Effect of tart cherry juice (Prunus Cerasus) on melatonin levels and enhanced sleep quality, Eur. J. Nutr. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Consumption of an antioxidant does not guarantee that the compound will act as an antioxidant within the body, so positive findings from one antioxidant or combination of antioxidants cannot be generalised.

    “Consumption of an antioxidant does not guarantee that the compound will act as an antioxidant within the body, therefore positive findings from one antioxidant or combination of antioxidants cannot be generalised [59].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [59] Nieman, D.C., and Mitmesser, S.H. (2017). Potential Impact of Nutrition on Immune System Recovery from Heavy Exertion: A Metabolomics Perspective. Nutrients, 9. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Total antioxidant capacity was increased in both groups post-race and remained elevated at 24 h in the intervention group but not the control group.

    “Total antioxidant capacity was increased in both groups post-race (intervention 124% of baseline and control 112% of baseline, p < 0.01) and remained elevated at 24 h in the intervention group (114% of baseline) but not the control group [67].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [67] Howatson, 2010, Influence of tart cherry juice on indices of recovery following marathon running, Scan. J. Med. Sci. Sports source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Elevated melatonin concentrations may not be the only mechanism by which tart cherry juice improves sleep, as sleep regulation is also influenced by proinflammatory cytokines.

    “It must be noted that elevated melatonin concentrations may not be only mechanism at work as sleep regulation is also influenced by proinflammatory cytokines [3].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [3] Irwin, 2017, Sleep health: Reciprocal regulation of sleep and innate immunity, Neuropsychopharmacology source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In a comparison of food bars, Food 1 (25 g deoiled butternut squash seed meal and 25 g dextrose) and Food 2 (250 mg pharmaceutical tryptophan) produced significant results (p ≤ 0.05) for reduction of time awake during the night (19.2% and 22.1%), increased sleep efficiency (5.19% and 7.36%) and increased subjective sleep quality (12.2% and 11.8%).

    “Food 1 and Food 2 produced significant results (p ≤ 0.05) for reduction of time awake during the night (19.2% and 22.1%), increased sleep efficiency (% of time spent in bed; asleep) (5.19% and 7.36%) and increased subjective sleep quality (12.2% and 11.8%) [53], indicating that relatively small doses (250 mg) of dietary tryptophan can positively impact sleep.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [53] Hudson, 2005, Protein source tryptophan versus pharmaceutical grade tryptophan as an efficacious treatment for chronic insomnia, Nutr. Neurosci. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Despite increased markers of oxidative stress and inflammation in the vitamin E intervention group, there was no significant difference between the groups in terms of race performance.

    “Interestingly, despite increased markers of OS and inflammation in the intervention group, there was no significant difference between the groups in terms of race performance.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [60] Nieman, 2004, Vitamin E and immunity after the Kona triathlon world championship, Med. Sci. Sports Exerc. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    The range of phenolic compounds in cherries, which have anti-inflammatory and antioxidant properties, may enhance post-exercise recovery as well as sleep.

    “The range of phenolic compounds in cherries which have anti-inflammatory and antioxidant properties may enhance post exercise recovery as well as sleep [50].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [50] Howatson, 2012, Effect of tart cherry juice (Prunus Cerasus) on melatonin levels and enhanced sleep quality, Eur. J. Nutr. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Antioxidants are heterogeneous, function in a distinct manner, and do not solely regulate ROS.

    “It must be noted that antioxidants are heterogeneous, they function in a distinct manner and do not solely regulate ROS [61].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [61] Finaud, 2006, Oxidative stress, Sports Med. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Antioxidants reduce oxidative stress, play a key role in immunity, and may improve recovery following exercise.

    “Antioxidants reduce OS, play a key role in immunity and may improve recovery following exercise [58,59].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [58] Halliwell, B., and Gutteridge, J.M. (2015). Free Radicals in Biology and Medicine, Oxford University Press. source

      Not checked in the free run.

    • cites [59] Nieman, D.C., and Mitmesser, S.H. (2017). Potential Impact of Nutrition on Immune System Recovery from Heavy Exertion: A Metabolomics Perspective. Nutrients, 9. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Tart cherry juice supplementation increased circulating melatonin levels and improved sleep time and quality in healthy adults.

    “This was the first investigation to demonstrate that tart cherry juice supplementation increased circulating melatonin levels and improved sleep time and quality in healthy adults.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [50] Howatson, 2012, Effect of tart cherry juice (Prunus Cerasus) on melatonin levels and enhanced sleep quality, Eur. J. Nutr. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In healthy adults (n = 14) with sleep complaints, evening ingestion of α-lactalbumin (20 g) resulted in a 130% increase in tryptophan:LNAA prior to bed and a modest but significant reduction in morning sleepiness and improved alertness the following morning.

    “In a similar study, healthy adults (n = 14) with sleep complaints consumed milkshakes containing either α-lactalbumin (20 g) or a casein placebo. Evening ingestion of α-lactalbumin resulted in a 130% increase in tryptophan:LNAA prior to bed and modest but significant reduction in morning sleepiness and improved alertness the following morning [55].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [55] Markus, 2005, Evening intake of α-lactalbumin increases plasma tryptophan availability and improves morning alertness and brain measures of attention, Am. J. Clin. Nutr. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Antioxidant consumption may influence recovery from exercise but may also influence sleep since sleep regulation is influenced by pro-inflammatory cytokines.

    “Antioxidant consumption may influence recovery from exercise but may also influence sleep since sleep regulation is influenced by pro-inflammatory cytokines [59].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [59] Nieman, D.C., and Mitmesser, S.H. (2017). Potential Impact of Nutrition on Immune System Recovery from Heavy Exertion: A Metabolomics Perspective. Nutrients, 9. source

      Not checked in the free run.

    • Rests on an assumption: Both the general population and athletes can benefit from nutritional and supplementation support to boost immunity and reduce acute and chronic inflammation during periods of increased training load and competition.

  • May combine two claims.

    Premisecitation

    Niacin can be synthesised endogenously from tryptophan via the Kynurenine Pathway, therefore consuming sufficient niacin is necessary to inhibit 2,3-dioxygenase activity, eliciting a tryptophan sparing effect and increasing tryptophan availability for serotonin and melatonin synthesis.

    “Niacin can be synthesised endogenously from tryptophan via the Kynurenine Pathway, therefore, consuming a sufficient amount of niacin is necessary to inhibit 2,3-dioxygenase activity eliciting a tryptophan sparing effect, increasing its availability for synthesis serotonin and melatonin [40].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Vitamin B12 contributes to melatonin secretion, pyridoxine is involved in the synthesis of serotonin from tryptophan, and niacin may elicit a tryptophan sparing effect.

    “Vitamin B12 contributes to melatonin secretion, pyridoxine (vitamin B6) is involved in the synthesis of serotonin from tryptophan and niacin (vitamin B3) may elicit a tryptophan sparing effect [40].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Pyridoxine's role in the conversion of tryptophan into serotonin is related to the amino acid decarboxylase, which speeds up the conversion rate of 5-HT to serotonin.

    “Pyridoxine’s role in the conversion of tryptophan into serotonin is related to the amino acid decarboxylase which speeds up the conversion rate of 5-HT to serotonin [45].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [45] Oliver, 2017, Sleep improvement in athletes: Use of nutritional supplements, Am. J. Sports Med.

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The reduced form of folate increases tetrahydrobiopterin, a co-enzyme of tryptophan-5-hydroxylase, which converts tryptophan into 5-HT.

    “The reduced form of folate (5-methyltetratrahydrofolate) increases tetrahydrobiopterin is a co-enzyme of tryptophan-5-hydroxylase which converts tryptophan into 5-hydroxytryptamine (5-HT) [45].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [45] Oliver, 2017, Sleep improvement in athletes: Use of nutritional supplements, Am. J. Sports Med.

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Magnesium is believed to enhance melatonin secretion, promoting sleep onset, and act as a GABA agonist.

    “Magnesium is also believed to enhance melatonin secretion promoting sleep onset and act as a GABA agonist, the main inhibitory neurotransmitter that acts on the CNS [40].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductcitation

    The kiwifruit sleep study lacked a control group and had a high level of subject drop out (n = 5).

    “the lack of a control group must be noted and there was a high level of subject drop out (n = 5).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [70] Lin, 2011, Effect of kiwifruit consumption on sleep quality in adults with sleep problems, Asia Pac. J. Clin. Nutr.

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    The high folate content in kiwifruit may improve folate status and consequently improve sleep.

    “the high folate content in kiwifruit may improve folate status and consequently improve sleep [70].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [70] Lin, 2011, Effect of kiwifruit consumption on sleep quality in adults with sleep problems, Asia Pac. J. Clin. Nutr.

      Not checked in the free run.

    • Rests on an assumption: Folates are destroyed by cooking or processing, but kiwifruit are typically consumed in their raw form.

  • May combine two claims.

    Premisecitation

    Mixed effects have been observed with different doses of cobalamin (vitamin B12) on sleep-wake rhythms and delayed sleep phase syndrome, while no effect was observed for sleep duration.

    “Mixed effects have been observed, with different doses of cobalamin (vitamin B12) on sleep-wake rhythms and delayed sleep phase syndrome (a significant delay in circadian rhythm), while no effect was observed for sleep duration [41].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [41] Roehrs, 2001, Sleep, sleepiness, and alcohol use, Alcohol. Res. Health

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Serotonin is the end product of L-tryptophan metabolism and is related to REM sleep.

    “Serotonin is the end product of L-tryptophan metabolism and is related to REM [70].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [70] Lin, 2011, Effect of kiwifruit consumption on sleep quality in adults with sleep problems, Asia Pac. J. Clin. Nutr.

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Folate deficiency has been linked to insomnia and restless leg syndrome.

    “Folate deficiency has been linked to insomnia (difficulty initiating or maintaining sleep, extended periods of wakefulness and/or insufficient sleep) and restless leg syndrome (repeated movement of or undesirable sensations in legs leading to sleep disruption) [70]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [70] Lin, 2011, Effect of kiwifruit consumption on sleep quality in adults with sleep problems, Asia Pac. J. Clin. Nutr.

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The serotonin content in kiwifruit may contribute to improved sleep, while the rich antioxidant content may suppress free radical expression and inflammatory cytokines.

    “The serotonin content in kiwifruit may contribute to improved sleep while the rich antioxidant content may supress free radical expression and inflammatory cytokines.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    Sleep can be promoted either by inhibiting wake-promoting mechanisms or by increasing sleep-promoting factors through nutritional interventions.

    “Sleep can be promoted either by inhibiting wake-promoting mechanisms or by increasing sleep promoting factors through nutritional interventions [40].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [40] Peukhuri, 2012, Diet promotes sleep duration and quality, Nutr. Res. source

      Not checked in the free run.

66 of 66

  • The paper relies on this without support.

    Athletes’ physical and mental recovery needs may be greater due to the high physiological and psychological demands placed on them during training and competition.

    “particularly for athletes whose physical and mental recovery needs may be greater due to the high physiological and psychological demands placed on them during training and competition.”

  • The paper relies on this without support.

    Sleep disturbances and short sleep duration can be modified to promote sleep health.

    “Sleep disturbances and short sleep duration are behavioural risk factors for inflammation, associated with increased risk of illness and disease, which can be modified to promote sleep health.”

  • The paper relies on this without support.

    The effect of exogenous melatonin on sleep quality is relative to the person’s endogenous melatonin levels.

    “However, the effect is relative to the person’s endogenous melatonin levels.”

  • The paper relies on this without support.

    Both the general population and athletes can benefit from nutritional and supplementation support to boost immunity and reduce acute and chronic inflammation during periods of increased training load and competition.

    “Both the general population and athletes can benefit from nutritional and supplementation support to boost immunity and reduce acute and chronic inflammation during periods of increased training load and competition.”

  • The paper relies on this without support.

    Supplementing magnesium, zinc, and melatonin will most likely only have an effect in cases of deficiency or insufficiency.

    “It must be noted that supplementing these nutrients will most likely only have an effect in cases of deficiency or insufficiency.”

  • The paper relies on this without support.

    Folates are destroyed by cooking or processing, but kiwifruit are typically consumed in their raw form.

    “Although folates are widely consumed in the diet, they are destroyed by cooking or processing, however, kiwifruit are typically consumed in their raw form.”
6 of 6

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Sleep efficiency is reported in minutes despite being defined as a percentage

    Minor

    The paper defines sleep efficiency as a percentage of time in bed spent asleep, but gives the kiwifruit study's baseline and post-intervention sleep-efficiency values in minutes.

  • Arousal-system activation is said to facilitate sleep

    Minor

    The account says that arousal-system activation inhibits sleep-active neurons yet facilitates sleep. Elsewhere, it describes activation of sleep-promoting neurons as reinforcing sleep episodes.

2 of 2

Cites

Flagged first, then by citations

3 of the 75 references couldn’t be matched to a known paper.

Research works printed but not linked: 3

  1. Kryger, M.H., Roth, R., and Dement, W.C. (2011). Monitoring and Staging Human Sleep. Principles and Practice of Sleep Medicine, Elsevier. [5th ed.].
  2. Kryger, M.H., Roth, T., and Dement, W.C. (2011). Principles and Practice of Sleep Medicine, Elsevier. [5th ed.].
  3. Oliver, 2017, Sleep improvement in athletes: Use of nutritional supplements, Am. J. Sports Med., 34, 93

Cited by

Sorted by citations

Related

Authors
Doherty, R., Madigan, S., Warrington, G., & Ellis, J.
Affiliations
  • Letterkenny Institute of Technology (IE)
  • Sport Ireland Institute (IE)
  • University of Limerick (IE)
  • Northumbria University (GB)
Corresponding author
Doherty, Rónán
ORCID
Venue
Nutrients
Publisher
MDPI AG
Published
2019-04-11
Volume
11
Issue
4
Pages
822
ISSN
2072-6643 (ISSN-L)
DOI
10.3390/nu11040822
PMC
PMC6520871
OpenAlex
W2938906146
Semantic Scholar
f51ed80aa0d48ac433b8a28592e9cbf85226e685
Cited by
186
References
75
Citations by year
2026: 22 · 2025: 34 · 2024: 31 · 2023: 31 · 2022: 28 · 2021: 23 · 2020: 15 · 2019: 1
FWCI
2.47
Type
journal article
Language
en
Open access
Licence
Locations
  • Nutrients (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • University of Limerick Institutional Repository (University of Limerick) (acceptedVersion, other-oa)
  • Northumbria Research Link (Northumbria University) (submittedVersion)
  • Arrow@dit (Dublin Institute of Technology) (submittedVersion, cc-by-nc-sa)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by-nc-sa)
  • Lenus, The Irish Health Repository (Dr Steevens Hospital Library) (submittedVersion)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
Keywords
sleep, nutrition, athletes, sleep quality, sleep duration, sleep disorders, inflammation, melatonin, tryptophan, tart cherry juice, kiwifruit, micronutrients, carbohydrate intake, immune system, recovery, functional foods, sleep health
MeSH terms
Prunus avium, Antioxidants, Circadian Rhythm, Diet, Dietary Carbohydrates, Fruit, Humans, Melatonin, Nutritional Physiological Phenomena, Sleep, Sleep Wake Disorders, Tryptophan, Vitamin B Complex, Glycemic Index, Athletic Performance, Athletes

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