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Cited by 70Sports Performance and TrainingMuscle metabolism and nutritionCardiovascular and exercise physiology

Periodization of carbohydrate intake: short-term effect on performance

Open access
Marquet, Laurie-Anne, Hausswirth, Christophe, Molle, Odeline, Hawley, John, Burke, Louise, Tiollier, Eve, Brisswalter, Jeanick·2016·Nutrients
DOI 10.3390/nu8120755PMC PMC5188410
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Abstract

Background: “Sleep-low” consists of a sequential periodization of carbohydrate (CHO) availability—low glycogen recovery after “train high” glycogen-depleting interval training, followed by an overnight-fast and light intensity training (“train low”) the following day. This strategy leads to an upregulation of several exercise-responsive signaling proteins, but the chronic effect on performance has received less attention. We investigated the effects of short-term exposure to this strategy on endurance performance. Methods: Following training familiarization, 11 trained cyclists were divided into two groups for a one-week intervention—one group implemented three cycles of periodized CHO intake to achieve the sleep-low strategy over six training sessions (SL, CHO intake: 6 g·kg−1·day−1), whereas the control group consumed an even distribution of CHO over the day (CON). Tests were a 2 h submaximal ride and a 20 km time trial. Results: SL improved their performance (mean: +3.2%; p < 0.05) compared to CON. The improvement was associated with a change in pacing strategy with higher power output during the second part of the test. No change in substrate utilization was observed after the training period for either group. Conclusion: Implementing the “sleep-low” strategy for one week improved performance by the same magnitude previously seen in a three-week intervention, without any significant changes in selected markers of metabolism.

AI snapshot

Written from the paper’s full text.

TL;DR

One week of periodized carbohydrate intake using the “sleep-low” strategy improved 20 km cycling time-trial performance in trained cyclists (+3.2%) compared with an even CHO distribution, with no significant changes in substrate utilization or blood metabolic markers. The improvement was linked to altered pacing (higher power in later kilometers) rather than measured metabolic adaptations.

Key findings

  • The sleep-low (SL) group reduced 20 km time-trial time by −3.23% ± 2.99% (p < 0.05, d = 1.58) and increased mean power from 229 ± 36 to 250 ± 32 W (p < 0.05, d = 1.48); the control (CON) group showed no significant time change (−1.04% ± 3.46%).
  • SL had higher mean power at the 11th–17th kilometers (e.g., 15th km: +21.2% ± 12.8%, p < 0.01, d = 2.95), whereas CON showed no change; both groups developed higher mean power at the 20th kilometer.
  • No significant changes were observed in substrate oxidation: SL CHO oxidation was 2.0 ± 0.2 vs. 2.1 ± 0.2 g·min−1 and fat oxidation 0.6 ± 0.3 vs. 0.9 ± 0.2 g·min−1 pre-to-post; blood glycerol, free fatty acids, and catecholamines increased during the submaximal test but did not differ between groups or PRE/POST.
  • Fat mass decreased only in SL (−395 ± 491 g, p < 0.05, d = 0.34; CON: −151 ± 363 g, not significant); RPE during the time trial was unchanged, but LIT training RPE was higher in SL (15.2 ± 1.9) than CON (13.5 ± 2) (p < 0.05, d = 0.87).

Methods

  • Randomized one-week intervention after familiarization and PRE testing: both groups completed the same six training sessions over six consecutive days, including afternoon HIT (8 × 5 min at 85% MAP, 1 min recovery at 100 W) and next-morning LIT (1 h at 65% MAP). CHO intake was 6 g·kg−1·day−1 in both groups, but SL withheld CHO from the HIT session until after the following morning’s LIT, while CON consumed CHO evenly across the day.
  • Participants were 11 endurance-trained male cyclists (mean ± SD: age 31.2 ± 7.1 years; body mass 71.1 ± 5.6 kg; V̇O2max 64.2 ± 6.0 mL·min−1·kg−1; MAP 342 ± 38.3 W); group sizes were reported as CON n = 9 and SL n = 12.
  • Testing included a 2 h submaximal ride at 60% MAP followed immediately by a 20 km time trial; food diaries, blood markers, and DXA body composition were assessed. Main analysis used repeated-measures ANOVA with Newman–Keuls post hoc tests, Cohen’s d effect sizes, and p < 0.05.

Limitations

  • Stated: the study could not be blinded because dietary intake differed between groups; participants were not informed of the aim, group assignment, or the other group’s program.
  • Stated: participants were free-living and prepared their own meals, so slight deviations from dietary control were possible; the authors note a trend for increased energy and CHO intake in SL between PRE and POST while CON slightly reduced intake, which could bias outcomes. They also state they were unable to measure muscle glycogen, leaving the proposed glycogen mechanism untested.
  • Evident from the text: the sample was small and all male, the intervention lasted only one week, and the reported group sizes (CON n = 9, SL n = 12) are inconsistent with the stated total of 11 cyclists; performance tests were conducted under high CHO availability, which the authors suggest may explain the absence of metabolic changes.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.3390/nu8120755

Cites

34 of 34 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 45 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    No significant changes in selected markers of metabolism occurred after the one-week sleep-low intervention.

    “Implementing the “sleep-low” strategy for one week improved performance by the same magnitude previously seen in a three-week intervention, without any significant changes in selected markers of metabolism.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The sleep-low protocol achieved low muscle glycogen concentrations during recovery and the following morning LIT session.
  • Findingown data

    No change in substrate utilization was observed after the training period for either group.

    “No change in substrate utilization was observed after the training period for either group.”
    Quote in the paperSubstantial claim
  • Findingown data

    A one-week implementation of the sleep-low strategy improved endurance performance compared to a control group (mean +3.2%, p < 0.05).

    “SL improved their performance (mean: +3.2%; p < 0.05) compared to CON.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The sleep-low protocol achieved low muscle glycogen concentrations during recovery and the following morning LIT session.
    • Rests on an assumption: Participants accurately recorded and complied with their dietary intake via daily food diaries.
  • Findingown data

    The performance improvement in the sleep-low group was associated with a change in pacing strategy, with higher power output during the second part of the test.

    “The improvement was associated with a change in pacing strategy with higher power output during the second part of the test.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The sleep-low protocol achieved low muscle glycogen concentrations during recovery and the following morning LIT session.
    • Rests on an assumption: Participants accurately recorded and complied with their dietary intake via daily food diaries.
  • Findingown data

    Subjects in the SL group perceived the LIT training sessions as harder than subjects in the CON group during the intervention.

    “Subjects who trained in a fasted state (SL group) perceived the LIT training sessions as harder (15.2 ± 1.9) than the subjects of the CON group (13.5 ± 2) (p < 0.05, d = 0.87).”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 18
  • May combine two claims. 12

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

    Findingown data

    Plasma glycerol concentrations increased during the submaximal cycling test.

    “Plasma concentrations of glycerol increased during the submaximal cycling test (p < 0.001) but differences between groups or between PRE and POST tests were not significant (Table 3).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    There were no significant differences between groups or between PRE and POST tests in plasma glycerol concentrations.

    “Plasma concentrations of glycerol increased during the submaximal cycling test (p < 0.001) but differences between groups or between PRE and POST tests were not significant (Table 3).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    There were no significant differences between groups or between PRE and POST tests in plasma free fatty acid concentrations.

    “Similarly, there was an increase in plasma concentrations of free fatty acids during the test (p < 0.001) but without any difference between groups or between PRE and POST tests.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    No significant difference in plasma catecholamine concentrations was observed before and after the training/diet intervention or between groups.

    “No significant difference in plasma catecholamine concentrations were observed before and after the training/diet intervention or between groups (Table 3).”
    Quote in the paperNot a substantial claim

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

    Findingown data

    Total protein intake increased from baseline to the training diet week in both SL and CON groups.

    “Total protein intake increased between the baseline training period and the training diet week (+36.3% and +20.4%, p < 0.05, d = 3.48 and d = 1.07, for SL and CON groups, respectively) but without any difference between groups.”
    Quote in the paperNot a substantial claim

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

    Findingown data

    Plasma catecholamine concentrations increased during the submaximal cycling test, with concentrations at 1 h and 2 h higher than resting for both groups.

    “Plasma catecholamine concentrations increased during the submaximal cycling test: the concentrations at 1 h and at 2 h were higher than resting concentrations for both groups (p < 0.01 for both markers).”
    Quote in the paperNot a substantial claim

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

    Findingown data

    Plasma free fatty acid concentrations increased during the submaximal cycling test.

    “Similarly, there was an increase in plasma concentrations of free fatty acids during the test (p < 0.001) but without any difference between groups or between PRE and POST tests.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    There are challenges to the feasibility of free-living athletes achieving the required dietary manipulations and/or having the commitment to undertake the low CHO recovery and subsequent training.

    “we note challenges to the feasibility of free-living athletes achieving the required dietary manipulations and/or having the commitment to undertake the low CHO recovery and subsequent training [21].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [21] Stellingwerf, 2012, Case study: Nutrition and training periodization in three elite marathon runners, Int. J. Sport Nutr. Exerc. Metab. source

      Not checked in the free run.

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

    Study design and conductreasoning

    The study could not be performed as a blinded intervention because dietary intake differences between groups could not be disguised.

    “Since it was not possible to disguise the differences in dietary intake between the groups, this study could not be performed as a blinded intervention.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Meals during the 24 h prior to testing sessions were identically prescribed for both groups to ensure the same total CHO intake (6 g·kg−1·day−1).

    “Meals during the 24 h prior to the testing sessions (lunch, dinner, and breakfast) were identically prescribed for both groups to ensure that the same amount of CHO (total intake of 6 g·kg−1·day−1) was consumed.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Nutritional recommendations for competition performance promote strategies to achieve high CHO availability, including adequate pre-exercise glycogen concentrations and additional CHO intake during competition.

    “Thus, nutritional recommendations for competition performance promote strategies to achieve “high CHO availability”, in the form of adequate pre-exercise glycogen concentrations and additional CHO intake during competition to meet the specific fuel needs of the event [1,2].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [1] Burke, 2011, Carbohydrates for training and competition, J. Sports Sci. source

      Not checked in the free run.

    • cites [2] Thomas, 2016, Position of the academy of nutrition and dietetics, dietitians of Canada, and the American college of sports medicine: Nutrition and athletic performance, J. Acad. Nutr. Diet. source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductreasoning

    To limit bias, participants were not informed of the aim of the study, the number of groups, their group assignment, or the other group's program.

    “In order to limit this bias, participants were not informed of the aim of the study (periodization of the CHO intake). They were neither aware of the number of groups in the study, the group to which they had been assigned, nor the program of the other group.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The three-week sleep-low program had no negative impact on immune function or sleep quality.

    “Furthermore, the performance improvements achieved by the SL program were associated with a decrease in body fat (−1.05%) [15] without any negative impact on immune function or sleep quality [16].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [16] Louis, 2016, The impact of sleeping with reduced glycogen stores on immunity and sleep in triathletes, Eur. J. Appl. Physiol. source

      Not checked in the free run.

    • Rests on an assumption: The sleep-low protocol achieved low muscle glycogen concentrations during recovery and the following morning LIT session.

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    All blood samples were analyzed in a single batch at the end of the study to avoid interassay variation.

    “To avoid interassay variation, all blood samples were analyzed in a single batch at the end of the study.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The sleep-low strategy allows athletes to perform high intensity training sessions supported by high CHO availability while enhancing metabolic adaptation associated with low glycogen availability.

    “The “sleep-low” (SL) strategy represents one such sequence of periodized CHO availability, which allows athletes to perform high intensity training sessions supported by high CHO availability while enhancing metabolic adaptation associated with low glycogen availability [14,15,16,17].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [14] Lane, 2015, Effects of sleeping with reduced carbohydrate availability on acute training responses, J. Appl. Physiol. source

      Not checked in the free run.

    • cites [15] Marquet, 2016, Enhanced endurance performance by periodization of carbohydrate intake: “Sleep Low” strategy, Med. Sci. Sports Exerc. source

      Not checked in the free run.

    • cites [16] Louis, 2016, The impact of sleeping with reduced glycogen stores on immunity and sleep in triathletes, Eur. J. Appl. Physiol. source

      Not checked in the free run.

    • cites [17] Impey, 2016, Fuel for the work required: A practical approach to amalgamating train-low paradigms for endurance athletes, Physiol. Rep. source

      Not checked in the free run.

    • Rests on an assumption: The sleep-low protocol achieved low muscle glycogen concentrations during recovery and the following morning LIT session.

  • Classified as probably not a substantial claim.

    Study design and conductown data

    Subjects were randomly assigned to two groups.

    “Then, they were randomly assigned to two different groups undertaking the same one-week training program but following different nutritional guidelines”
    Quote in the paperSubstantial claim

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

    Study design and conductnone given

    Dietary compliance was checked by requiring participants to complete a daily food diary.

    “To check compliance to the dietary protocols, participants were required to complete a daily food diary.”
    Quote in the paperNot a substantial claim

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

    Premisecitation

    The "sleep-low" strategy leads to increased activity of several exercise-responsive signaling proteins with putative roles in training adaptation (e.g., AMPK, p38 MAPK, p53).

    “This strategy leads to an upregulation of several exercise-responsive signaling proteins”
    • Also stated in: § 1. Introduction · hedged
      “Previous studies have reported that this strategy leads to increased activity of several proteins with putative roles in training adaptation (AMPK, p38 MAPK, p53) [9,14]”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [9] Bartlett, 2013, Reduced carbohydrate availability enhances exercise-induced p53 signaling in human skeletal muscle: Implications for mitochondrial biogenesis, Am. J. Physiol. Regul. Integr. Comp. Physiol. source

      Not checked in the free run.

    • cites [14] Lane, 2015, Effects of sleeping with reduced carbohydrate availability on acute training responses, J. Appl. Physiol. source

      Not checked in the free run.

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

    Study design and conductnone given

    The gas and flow analyzers were calibrated prior to each test using ambient air, known-concentration gas, and a 3 L syringe.

    “The gas and flow analyzers were calibrated prior to each test using ambient air, known-concentration gas (O2 = 16%, CO2 = 5%), and a 3 L syringe.”
    Quote in the paperNot a substantial claim

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

    Study design and conductnone given

    Saddle and handlebar heights were standardized between sessions.

    “Saddle and handlebar heights were set to match the usual positions used by participants, and these were standardized between sessions.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Previous studies on training with low glycogen availability typically report higher activity of enzymes involved in fat metabolism, changes in transcription for adaptive genes, or factors involved in mitochondrial biogenesis.

    “Typically, these studies report higher activity of enzymes involved in fat metabolism [12,13], and changes in transcription for adaptive genes [14] or factors involved in mitochondrial biogenesis [17].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [12] Yeo, 2008, Skeletal muscle adaptation and performance responses to once a day versus twice every second day endurance training regimens, J. Appl. Physiol. source

      Not checked in the free run.

    • cites [13] Hulston, 2010, Training with low muscle glycogen enhances fat metabolism in well-trained cyclists, Med. Sci. Sports Exerc. source

      Not checked in the free run.

    • cites [14] Lane, 2015, Effects of sleeping with reduced carbohydrate availability on acute training responses, J. Appl. Physiol. source

      Not checked in the free run.

    • cites [17] Impey, 2016, Fuel for the work required: A practical approach to amalgamating train-low paradigms for endurance athletes, Physiol. Rep. source

      Not checked in the free run.

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

    Study design and conductnone given

    Before entering the study, all participants were examined by a cardiologist to ensure they did not present with abnormal electrocardiograph pattern or contraindications to physical activity.

    “Before entering the study, all participants were examined by a cardiologist to ensure they did not present with abnormal electrocardiograph pattern or contraindications to physical activity.”
    Quote in the paperNot a substantial claim

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

    Study design and conductown data

    The study protocol was approved by a local Ethics Committee.

    “The study’s protocol was approved by local Ethic Committee 2015-AO1136-43 (Paris IDF X, France).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    The findings show the importance of pacing in determining performance and suggest factors other than physiological or metabolic characteristics previously reported in low glycogen availability studies.

    “These findings show the importance of pacing in the determination of performance, and suggest factors other than physiological or metabolic characteristics that have been previously reported in studies focusing on the effect of low glycogen availability during training [7].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [7] Hawley, 2007, International Association of Athletics Federations Innovations in athletic preparation: Role of substrate availability to modify training adaptation and performance, J. Sports Sci. source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data

    One limitation of the study is a trend for increased energy and CHO intake in the SL group between PRE and POST testing sessions, while it was slightly reduced for the CON group.

    “One limitation of our study which could also explain the possibly higher muscular glycogen content is the trend for an increase in energy and CHO intake for the SL group between PRE and POST testing sessions, while it was slightly reduced for the CON group.”
    Quote in the paperSubstantial claim

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

    Premisecitation

    Rauch et al. proposed that power output is dependent on the brain anticipating the rate of muscle glycogen utilization, leading to individual critical levels of endpoint muscle glycogen.

    “Rauch et al. [34] proposed that the power output developed is dependent on the brain, which anticipates the rate of muscle glycogen utilization leading to individual “critical” levels of endpoint muscle glycogen.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [34] Rauch, 2005, A signalling role for muscle glycogen in the regulation of pace during prolonged exercise, Br. J. Sports Med. source

      Not checked in the free run.

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

    Study design and conductnone given

    Participants were not informed of their results until the end of the study.

    “Participants were not informed of their results until the end of the study.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    The enhanced performance in the SL group was related to differences in pacing strategy and higher self-chosen power outputs.

    “This enhanced performance was related to differences in pacing strategy, and higher levels of self-chosen power outputs in the athletes who undertook the periodized CHO intake protocol.”
    Quote in the paperSubstantial claim

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

    Study design and conductown data

    All participants provided written informed consent.

    “all participants provided their written informed consent to participate.”
    Quote in the paperNot a substantial claim
29 of 29

  • The paper relies on this without support.

    The sleep-low protocol achieved low muscle glycogen concentrations during recovery and the following morning LIT session.

    “recovery from this session and the completion of the LIT session was undertaken with low CHO availability due to depleted glycogen concentrations and an overnight fast (“sleep-low” and “train-low”, respectively).”

  • The paper relies on this without support.

    Participants accurately recorded and complied with their dietary intake via daily food diaries.

    “To check compliance to the dietary protocols, participants were required to complete a daily food diary.”

  • The paper relies on this without support.

    The HIT session was undertaken with high muscle glycogen concentrations.

    “the HIT session was undertaken with high muscle glycogen concentrations (“train-high”)”

  • The paper relies on this without support.

    Strategies that promote training adaptation with low CHO availability are commonly observed among athletes but are often implemented unintentionally or without strategy.

    “Strategies that promote training adaptation with low CHO availability (overnight-fasted training, low-glycogen training, low glycogen recovery periods) are commonly observed among athletes, but are often implemented unintentionally or without strategy.”
4 of 4

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?

  • 1-3 weeks of sleep-low training in elite triathletes and cyclists improves cycling efficiency (3.1%) compared with traditional train-high approaches.

    “Marquet et al. [40, 41] observed that 1–3 weeks of sleep-low training in elite triathletes and cyclists improves cycling efficiency (3.1%), 20 km cycling time-trial performance (3.2%) and 10 km running performance (2.9%) compared with traditional train-high approaches.”

    From Fuel for the Work Required: A Theoretical Framework for Carbohydrate Periodization and the Glycogen Threshold Hypothesis (2018) · cites this paper as [41]

    The Introduction reports that a previous three-week sleep-low study improved submaximal cycling efficiency relative to a control group. It gives no 3.1% figure, however, and this paper’s one-week study of trained cyclists found no significant effect on other physiological parameters (Discussion). The cited paper therefore does not establish a 3.1% efficiency improvement across one to three weeks in elite triathletes and cyclists. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • 1-3 weeks of sleep-low training in elite triathletes and cyclists improves 20 km cycling time-trial performance (3.2%) compared with traditional train-high approaches.

    “Marquet et al. [40, 41] observed that 1–3 weeks of sleep-low training in elite triathletes and cyclists improves cycling efficiency (3.1%), 20 km cycling time-trial performance (3.2%) and 10 km running performance (2.9%) compared with traditional train-high approaches.”

    From Fuel for the Work Required: A Theoretical Framework for Carbohydrate Periodization and the Glycogen Threshold Hypothesis (2018) · cites this paper as [41]

    The Results (§3.2.1; page not provided) report a 3.23% reduction in 20 km cycling time-trial time after one week of sleep-low training, with no comparable change in controls. The Study Population (§2.1) identifies the participants as endurance-trained male cyclists, not elite triathletes and cyclists. The paper mentions a separate three-week study, but this paper’s 20 km result comes from its one-week intervention. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • 1-3 weeks of sleep-low training in elite triathletes and cyclists improves 10 km running performance (2.9%) compared with traditional train-high approaches.

    “Marquet et al. [40, 41] observed that 1–3 weeks of sleep-low training in elite triathletes and cyclists improves cycling efficiency (3.1%), 20 km cycling time-trial performance (3.2%) and 10 km running performance (2.9%) compared with traditional train-high approaches.”

    From Fuel for the Work Required: A Theoretical Framework for Carbohydrate Periodization and the Glycogen Threshold Hypothesis (2018) · cites this paper as [41]

    The Introduction (section 1; page unavailable) reports that a previous three-week sleep-low study improved 10 km running performance by about 3% while its control group did not improve. This paper’s own one-week study tested cycling, not running, and describes its participants as endurance-trained rather than elite; it does not give a 2.9% running result. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Studies demonstrating beneficial effects on cell signalling and performance adaptations have completely restricted CHO after the evening training session and after subjects were fed a protein-only meal or beverage.

    “However, it is noteworthy that studies demonstrating beneficial effects on cell signalling [38] and performance adaptations [40, 41] have completely restricted CHO after the evening training session and after subjects were fed a protein-only meal or beverage.”

    From Fuel for the Work Required: A Theoretical Framework for Carbohydrate Periodization and the Glycogen Threshold Hypothesis (2018) · cites this paper as [41]

  • Early attempts to define an elite performer suggested 10 years or 10,000 hours are required to achieve expert level.

    “Early attempts to define an elite performer were based on time spent practicing a task, with suggestions that 10 years 14 or 10,000 hours 15 are required to achieve expert level.”

    From Defining Training and Performance Caliber: A Participant Classification Framework (2022) · cites this paper as [14]

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.

  • Claim of no other significant effects conflicts with fat-mass result

    Minor

    The discussion says there was no significant effect on any other physiological parameter, but the results report a significant reduction in fat mass in the SL group.

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Related

Authors
Marquet, L.-A., Hausswirth, C., Molle, O., Hawley, J., Burke, L., Tiollier, E., & Brisswalter, J.
Affiliations
  • Université Côte d'Azur (FR)
  • Institut National du Sport, de l'Expertise et de la Performance (FR)
  • Liverpool John Moores University (GB)
  • Australian Catholic University (AU)
Corresponding author
Marquet, Laurie-Anne
ORCID
Venue
Nutrients
Publisher
MDPI AG
Published
2016-11-25
Volume
8
Issue
12
Pages
755
ISSN
2072-6643 (ISSN-L)
DOI
10.3390/nu8120755
PMC
PMC5188410
OpenAlex
W2549673064
Cited by
70
References
34
Citations by year
2026: 3 · 2025: 3 · 2024: 8 · 2023: 2 · 2022: 7 · 2021: 9 · 2020: 12 · 2019: 12 · 2018: 9 · 2017: 5
FWCI
10.56
Type
journal article
Language
en
Open access
Licence
Locations
  • Nutrients (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Liverpool John Moores University (acceptedVersion, other-oa)
  • Research Bank (Australian Catholic University) (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
PepsiCo
Topics
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
  • Health Sciences › Medicine › Complementary and alternative medicine › Cardiovascular and exercise physiology
Keywords
carbohydrate intake, endurance performance, glycogen depletion, interval training, pacing strategy, trained cyclists, substrate utilization, time trial performance
MeSH terms
Adolescent, Adult, Bicycling, Diet, Dietary Carbohydrates, Exercise Test, Humans, Male, Oxygen Consumption, Periodicity, Physical Endurance, Exercise, Young Adult, Athletes, Sports Nutritional Physiological Phenomena

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