Technique labels are not treatment rules 9 October 2026 · Three new papers reinforce a practical boundary: foot-strike and cadence labels, force-pattern classifications and shoe sole thickness can describe selected mechanics, but they do not establish one universally safer or better way to run.
Narrative review · 2026-10-07
The Heel-Strike Fallacy and Cadence Beliefs in Distance Running: A Narrative Review. Source verification: checked. Read the source audit
A narrative review found no support for treating rearfoot striking as inherently harmful, 180 steps per minute as universally optimal, or cadence increases as a proven injury-prevention rule.
Limitations: Narrative rather than systematic review , mainly mechanistic evidence and disclosed professional affiliations; no direct ultra or sustained clinical outcome.
No universal foot-strike or cadence target follows.
PubMed (opens in a new tab) Cross-sectional biomechanics study · 2026-10-06
Exploring running classifications using foot inclination angle and ground reaction force clustering methods: Do traditional foot strike categories capture meaningful patterns in ground reactions forces? Source verification: checked. Read the source audit
In 103 collegiate cross-country runners, five ground-reaction-force clusters crossed the usual rearfoot, midfoot and forefoot categories.
Limitations: Cross-sectional mechanics at one self-selected pace; no symptoms, injury, retraining, trail, fatigue, ultra-duration or performance outcome.
A category label cannot replace a defined objective and observed response.
PubMed (opens in a new tab) Within-runner laboratory comparison · 2026-10-08
Running style and stability during uphill running are largely preserved with increasing shoe sole thickness. Source verification: checked. Read the source audit
In 17 experienced male runners on a 10% treadmill incline, 27, 35 and 50 mm sole conditions produced limited overall style and stability differences, alongside selected mechanical changes.
Limitations: Small male-only treadmill study with acute measures; no trail, fatigue, comfort, injury, race-performance or ultra-duration outcome.
Rehearse shoes in context; stack height alone does not select the best option.
PubMed (opens in a new tab) Energy, water and foot strike 2 October 2026 · Two newly indexed papers add useful boundaries rather than a new prescription: a two-runner 322 km case study quantifies exceptional energy expenditure and water turnover, while a 738-runner cohort found no association between rearfoot versus non-rearfoot pattern and one-year running-injury risk.
Field case study · 2026-09-25
Total Energy Expenditure and Water Turnover During a 322 Km Mountain Ultramarathon Source verification: checked. Read the source audit
In two runners completing 322 km, doubly labeled water measured total race energy expenditure of 29,376 and 38,909 kcal and water turnover of 35.2 and 47.5 L; the study does not establish 100K intake targets.
Limitations: Two cases in a much longer event; absolute expenditure and water turnover reflect event duration, rest time, environment and individual physiology and are not prescriptions.
Exceptional totals illustrate scale, not a universal fueling or hydration target.
PubMed (opens in a new tab) Prospective cohort analysis · 2026-09-25
Is a Runner's Footfall Pattern a Risk Factor for a Running-Related Injury? Using Data from the 4HAIE Cohort Study Source verification: checked. Read the source audit
In 738 runners followed for one year, rearfoot versus non-rearfoot footfall pattern was not associated with overall running-related injury risk or injury location.
Limitations: Secondary observational analysis; no randomized foot-strike retraining and no proof that changing strike pattern cannot affect symptoms or loading in a specific runner.
A foot-strike label is not a reliable injury-prevention shortcut.
PubMed (opens in a new tab) Downhill durability, load distribution and sensor limits 25 September 2026 · Four publications support gradual eccentric adaptation, conditional downhill technique cues and cautious interpretation of body-composition and sweat-sensor data. They reinforce the existing plan without creating a new universal dose.
Systematic review and meta-analysis · 2026-09-19
Neurophysiological and neuromuscular responses associated with the repeated bout effect following eccentric exercise Source verification: checked. Read the source audit
A systematic review of 12 studies found recovery-compatible changes after repeated eccentric exercise, while neural mechanisms remained limited or inconsistent.
Limitations: The pooled analyses were exploratory and did not test a universal downhill-running dose or ultramarathon outcome.
Keep downhill progression gradual, track immediate and 24- and 48-hour responses, avoid forcing foot-strike changes, and keep fueling or hydration decisions multi-source rather than sensor-controlled.
Neurophysiological and neuromuscular responses associated with the repeated bout effect following eccentric exercise (opens in a new tab) Biomechanical running study · 2026-09-23
Foot-strike pattern and lower-limb loading during downhill running Source verification: checked. Read the source audit
In 42 runners grouped by habitual foot-strike pattern, non-rearfoot strikers showed lower knee and higher ankle loading; downhill impact loading was not reduced.
Limitations: The study compared habitual groups running with their preferred pattern; it did not test a prescribed foot-strike change or establish injury prevention or performance benefit.
Keep downhill progression gradual, track immediate and 24- and 48-hour responses, avoid forcing foot-strike changes, and keep fueling or hydration decisions multi-source rather than sensor-controlled.
Foot-strike pattern and lower-limb loading during downhill running (opens in a new tab) Cross-sectional study · 2026-09-19
Predictive factors for running economy in female recreational runners Source verification: checked. Read the source audit
In 61 female recreational runners, body-composition and aerobic -speed measures were associated with running economy , but the cross-sectional design cannot establish causation.
Limitations: The sample was female and recreational, associations were observational, and weight loss was not tested as an intervention.
Keep downhill progression gradual, track immediate and 24- and 48-hour responses, avoid forcing foot-strike changes, and keep fueling or hydration decisions multi-source rather than sensor-controlled.
Predictive factors for running economy in female recreational runners (opens in a new tab) Measurement framework or perspective · 2026-09-19
Preserving sample, interface and signal fidelity in wearable sweat-electrolyte monitoring during exercise Source verification: checked. Read the source audit
Wearable sweat-electrolyte readings depend on sample, skin interface, sensor and signal-processing choices, creating multiple sources of measurement error.
Limitations: A measurement framework does not show that sensor-led sodium or fluid prescriptions improve safety or performance.
Keep downhill progression gradual, track immediate and 24- and 48-hour responses, avoid forcing foot-strike changes, and keep fueling or hydration decisions multi-source rather than sensor-controlled.
Preserving sample, interface and signal fidelity in wearable sweat-electrolyte monitoring during exercise (opens in a new tab) Sleep, soreness and the limits of recovery scores 18 September 2026 · Two checked papers from 12–18 September add context, not a new prescription. Wearable strain and perceived effort were weakly related in a small sample, while a soreness review did not establish a superior recovery treatment.
Exploratory observational study · 2026-09-17
Relationship between wearable activity strain and perceived exertion Source verification: checked. Read the source audit
Across paired observations from 11 female college athletes, perceived exertion and a proprietary wearable strain score were only weakly correlated.
Limitations: Small observational sample, proprietary metrics and no ultra-performance outcome.
Judge readiness from sleep, symptoms, perceived effort and comparable-session trends rather than one device score. Reduced soreness alone does not prove restored function or better 100K performance.
Relationship between wearable activity strain and perceived exertion (opens in a new tab) Systematic review with narrative synthesis · 2026-09-17
Mechanisms and management of exercise-induced muscle soreness Source verification: checked. Read the source audit
A broad review described interacting tissue, inflammatory and neural contributions to exercise-related soreness without establishing a superior recovery treatment.
Limitations: Populations and methods were heterogeneous, and extractable effects were insufficient for a new meta-analysis .
Judge readiness from sleep, symptoms, perceived effort and comparable-session trends rather than one device score. Reduced soreness alone does not prove restored function or better 100K performance.
Mechanisms and management of exercise-induced muscle soreness (opens in a new tab) Brain training, tired calves and what changes for a 100K 11 September 2026 · Seven publications offered useful but limited signals on mental fatigue, calf fatigue, drinking comfort, carbohydrate, stability measures, the microbiome and recovery nutrition. None justified rewriting the training plan.
Systematic review · 2026-09-11
Brain endurance training and endurance performance: systematic review Source verification: checked. Read the source audit
A review of 10 randomized trials reported benefits after induced mental fatigue, but running-specific evidence was small and effects without induced fatigue were inconclusive.
Limitations: Heterogeneity was high and running-relevant evidence had very low certainty.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Brain endurance training and endurance performance: systematic review (opens in a new tab) Small controlled experiment · 2026-09-07
Plantar-flexor fatigue redistributes lower-limb joint work during running Source verification: checked. Read the source audit
In 12 trained male runners, acute plantar-flexor fatigue shifted some joint-work contribution from the ankle toward the knee.
Limitations: Fatigue was induced experimentally and running lasted only 30 seconds at 10K pace.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Plantar-flexor fatigue redistributes lower-limb joint work during running (opens in a new tab) Small randomized crossover trial · 2026-09-10
Thirst satiation during exercise in the heat Source verification: checked. Read the source audit
In 12 men exercising in heat, small frequent drinks reduced thirst and slightly reduced perceived heat strain compared with the same fluid volume given intravenously.
Limitations: Cycling in a laboratory with an artificial comparator does not establish an optimal ultra drinking schedule.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Thirst satiation during exercise in the heat (opens in a new tab) Double-blind crossover trial · 2026-09-10
Carbohydrate ingestion and visual or neural fatigue during prolonged exercise Source verification: checked. Read the source audit
In 9 men cycling for 3 hours, carbohydrate maintained blood glucose but did not prevent a decline in rapid eye-movement speed.
Limitations: The small cycling study and its neural measure do not establish trail-running safety or ultra performance.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Carbohydrate ingestion and visual or neural fatigue during prolonged exercise (opens in a new tab) Systematic methodological review · 2026-09-09
Assessing running stability: a systematic review of methods Source verification: checked. Read the source audit
Across 43 studies, running-stability measures fell into linear, nonlinear and coordination-based approaches that describe different movement constructs.
Limitations: The review compared methods, not form-retraining interventions, and found no universal best score.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Assessing running stability: a systematic review of methods (opens in a new tab) Two-person case comparison · 2026-09-08
Microbiome observations in two runners from a 217-km mountain race Source verification: checked. Read the source audit
A post-hoc comparison of 2 runners from a 217-km mountain race is hypothesis-generating and cannot estimate a causal microbiome effect on performance.
Limitations: Two selected cases, confounding and unmeasured diet make causal interpretation unreliable.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Microbiome observations in two runners from a 217-km mountain race (opens in a new tab) Structured narrative review · 2026-09-06
Recovery nutrition after high-intensity exercise Source verification: checked. Read the source audit
A narrative review continued to place adequate carbohydrate and protein ahead of functional foods for recovery after high-intensity exercise.
Limitations: There was no pooled effect estimate and evidence for adjunct products was heterogeneous.
Keep the established plan: conversational effort, practiced fueling, small frequent drinking opportunities when useful, calf durability work and terrain-specific form cues. Do not add cognitive tasks, microbiome interventions or a recovery supplement from these findings.
Recovery nutrition after high-intensity exercise (opens in a new tab) Heat monitoring: context, not a training controller 4 September 2026 · Wearable heat monitoring can add context alongside the athlete, environment and established safety practices, but current evidence does not justify letting a proprietary score control training. Earlier foundational evidence on heat adaptation and environmental precautions.
Peer-reviewed perspective · 2026-09-01
Wearable technology and heat strain monitoring in sport and occupational settings Source verification: checked. Read the source audit
Multisensor wearables may help characterize heat strain, but device validity, signal loss, battery failure, individual variability and immature predictive algorithms limit their use as training controllers.
Limitations: This is a perspective, not a trial showing that wearable alerts prevent heat illness or improve endurance performance.
Sensor readings are one layer of a heat decision. Acclimatization and the event environment are separate considerations that cannot be replaced by a reassuring device score. This edition adds no temperature cutoff, fluid dose or unsupervised heat-training plan.
Wearable technology and heat strain monitoring in sport and occupational settings (opens in a new tab) Expert consensus informed by physiological research · 2015-05-23
Consensus Recommendations on Training and Competing in the Heat Source verification: unresolved. Read the source audit
Heat consensus identifies repeated exercise–heat exposure as a way to reduce physiological strain.
Limitations: This is a principle, not an unsupervised exposure programme.
Sensor readings are one layer of a heat decision. Acclimatization and the event environment are separate considerations that cannot be replaced by a reassuring device score. This edition adds no temperature cutoff, fluid dose or unsupervised heat-training plan.
Consensus Recommendations on Training and Competing in the Heat (opens in a new tab) Expert consensus informed by physiological research · 2015-05-23
Consensus Recommendations on Training and Competing in the Heat Source verification: unresolved. Read the source audit
The consensus also prioritizes shade, cooling access and event scheduling in hot conditions.
Limitations: Environmental precautions do not make wearable alerts a guarantee of safety.
Sensor readings are one layer of a heat decision. Acclimatization and the event environment are separate considerations that cannot be replaced by a reassuring device score. This edition adds no temperature cutoff, fluid dose or unsupervised heat-training plan.
Consensus Recommendations on Training and Competing in the Heat (opens in a new tab) Recovery fundamentals before recovery gadgets 28 August 2026 · A corrected 28 August edition found that recovery fundamentals deserve priority over optional recovery modalities. The historical source is reconstructed, while the retained review and its limits are explicit. Earlier foundational evidence on sleep and nutrition.
Systematic review and network meta-analysis · 2026-08-18
Physical recovery modalities in competitive and elite endurance athletes: a systematic review and network meta-analysis Source verification: checked. Read the source audit
Across 16 randomized trials with 273 competitive or elite endurance athletes, no physical recovery modality reliably outperformed passive recovery for sport-performance recovery.
Limitations: Certainty was mostly low or very low, modalities and outcomes varied, and reduced soreness does not prove restored function or ultra-race readiness.
Recovery devices should be evaluated against the outcome you actually need. Sleep opportunity and fuel restoration address different parts of recovery; neither validates a gadget score. The newer perspective is placed alongside older intervention and nutrition evidence without promising a faster ultra finish.
Physical recovery modalities in competitive and elite endurance athletes: a systematic review and network meta-analysis (opens in a new tab) Systematic review of 25 intervention studies · 2023-07-18
The Impact of Sleep Interventions on Athletic Performance: A Systematic Review Source verification: unresolved. Read the source audit
Sleep-extension interventions showed promising changes in selected performance tests.
Limitations: Small studies with bias concerns cannot quantify an ultra-race benefit.
Recovery devices should be evaluated against the outcome you actually need. Sleep opportunity and fuel restoration address different parts of recovery; neither validates a gadget score. The newer perspective is placed alongside older intervention and nutrition evidence without promising a faster ultra finish.
The Impact of Sleep Interventions on Athletic Performance: A Systematic Review (opens in a new tab) Narrative review · 2018-02-23
Restoration of Muscle Glycogen and Functional Capacity: Role of Post-Exercise Carbohydrate and Protein Co-Ingestion Source verification: checked. Read the source audit
Recovery nutrition research links restored fuel availability with capacity for another endurance bout.
Limitations: Evidence focuses on short laboratory recovery, not recovery gadgets.
Recovery devices should be evaluated against the outcome you actually need. Sleep opportunity and fuel restoration address different parts of recovery; neither validates a gadget score. The newer perspective is placed alongside older intervention and nutrition evidence without promising a faster ultra finish.
Restoration of Muscle Glycogen and Functional Capacity: Role of Post-Exercise Carbohydrate and Protein Co-Ingestion (opens in a new tab) Thresholds, heat, equipment and fueling: what transfers? 16 October 2026 · Three new laboratory studies examine personal thresholds, dry versus humid heat, and women’s equipment combinations. A clearly labelled 7 October cycling trial adds catch-up fueling evidence. Useful findings remain bounded by who was studied, what was measured and how long the test lasted.
Within-participant laboratory comparison · 2026-10-15
Ventilatory thresholds are detectable using DFA-α1 at group level but not individual level during swimming, cycling and running. Source verification: checked. Read the source audit
In 17 triathletes (13 men, 4 women), average DFA-α1 heart-rate variability values at measured ventilatory thresholds were near proposed cutoffs, but individual dispersion was large. This was group correspondence, not individual threshold validation.
Limitations: Small mixed-sex laboratory sample, mostly men; modality-specific testing and substantial individual variation. No prospective individual agreement, trail or ultra-performance validation.
Supports the existing distinction between a useful group marker and a validated personal training-zone boundary.
PubMed (opens in a new tab) Crossover heat-acclimation laboratory study · 2026-10-12
CrossAcclimation and Endurance Performance Following Adaptation to Dry and Humid Heat. Source verification: checked. Read the source audit
After 8 days of heat acclimation, average 30-minute laboratory time-trial power generally increased in trained male cyclists, with uncertainty varying by regimen and test environment. Dry acclimation produced a larger improvement in the dry test; humid-test improvements were similar after either regimen.
Limitations: Small male cycling conditions (dry n=10; humid n=12), short laboratory endpoint and no women or trail-ultra outcome. The humid-acclimation gain in the dry test was 6 W (90% credible interval −1 to 13 W), including no gain. Matched heat-stress index did not make the climates identical. This does not set an individual exposure dose or safety threshold.
Supports retaining humidity and event context when interpreting heat research; the study is not an eight-day prescription for runners.
PubMed (opens in a new tab) Four-condition within-runner laboratory comparison · 2026-10-12
Combined Effects of Sports Bra Support and Running Shoe Cushioning Influence Breast and Running Biomechanics in Female Runners. Source verification: checked. Read the source audit
In 27 recreational female runners, bra support affected breast acceleration and perceived comfort, while shoe cushioning affected tibial acceleration and shoe comfort. Some vibration-frequency measures also showed bra–shoe interactions.
Limitations: Acute laboratory mechanics and comfort; practical effect sizes, participant ages, longer use and trail conditions were not established from the abstract. No injury-incidence or ultra-performance endpoint and no product ranking.
Supports considering the equipment combination and the outcome being measured; lower acceleration alone does not prove injury protection.
PubMed (opens in a new tab) Randomized double-blind crossover cycling trial · 2026-10-07
Carbohydrate Intake of 100 vs. 60 g·h⁻¹ During Prolonged Cycling Improves Durability Without Altering Muscle Glycogen Utilization in Male Endurance Athletes. Source verification: checked. Read the source audit
Published on 7 October, this crossover trial compared 100 with 60 g carbohydrate per hour in 15 trained men during 4 hours of intermittent cycling. Late 15-minute time-trial power was 9 W higher with the larger intake, while muscle-glycogen use did not differ detectably.
Limitations: Catch-up from the prior evidence window, not a new publication this week. Small male-only cycling sample after carbohydrate-rich preparation; no women, trail running, ultra-duration or individual gastrointestinal-tolerance rule. Study doses describe the experiment, not advice.
Adds outcome-specific nutrition evidence without changing existing individualized, rehearsed fueling guidance or prescribing the larger study intake.
PubMed (opens in a new tab) When does a measurement become a useful decision? 23 October 2026 · Three new papers examine running-fatigue signals, interval-model transfer and palm cooling. Their useful findings depend on the measure, comparison and test setting. Older negative evidence and unfinished source work remain visible; existing ultra guidance stays unchanged.
Repeated-measures treadmill study · 2026-10-19
Power-Based Running Durability in Trained Runners: Preliminary Evidence of Speed-Adjusted Mechanical Drift as a Marker of Fatigue. Source verification: checked. Read the source audit
In 12 trained trail runners, device-derived contact measures changed during a 216-minute treadmill protocol while running economy and several power measures remained largely stable. During the fixed-speed phases, heart rate and perceived effort increased. Some uphill power differences were no longer significant after adjustment for speed.
Limitations: Small sample:6 women and 6 men pooled, with no sex-specific conclusion. Laboratory running with standardized fueling differs from a technical ultra. Proprietary sensor measures lacked concurrent criterion validation in the fatigued uphill trials. Speed adjustment is model dependent, not an isolated causal effect of fatigue. No individual cutoff, ideal form or training dose was validated.
Supports checking what a fatigue measure actually represents and retaining terrain, effort and fueling context; it does not validate a watch-based readiness decision.
PubMed / primary full text (opens in a new tab) Within-participant field model comparison · 2026-10-20
Original W'-balance models do not transfer to high-intensity interval training in trained adult runners: Proposal of a single-coefficient linear alternative. Source verification: checked. Read the source audit
In 27 trained runners, establishedW′-balance models overpredicted the intervals completed in two specific track sessions. A refitted linear model fitted those sessions more closely. Its reported errors came from the same 54 sessions used to fit it, not an independent prediction test.
Limitations: Mostly men, one fixed intensity/rest design and voluntary stopping. The model's empirical coefficient is not an established physiological trait. Small in-sample errors do not establish accuracy for a new runner, different session or ultra race. No automated interval prescription or individualized coaching tool follows.
Reinforces the existing distinction between model fit and validation; retain the established plan while checking independent validation before using a model to change it.
PubMed / primary full text (opens in a new tab) Narrative review with a structured search · 2026-10-18
Palmar Cooling as a Thermoregulatory Intervention: Mechanistic Basis and Implications for Exercise and Clinical Applications. Source verification: checked. Read the source audit
A review of 24 reports found mixed results for palm cooling across exercise tasks. Its authors rated endurance-performance evidence low and resistance-volume evidence very low. Positive findings coexist with null results; an older 12-person running trial did not detect a difference in total exercise time including warm-up; time to exhaustion was shorter with cooling.
Limitations: Nonregistered narrative synthesis, mostly small studies and only one validated sham comparison. Devices, timing and environments differed; two reports reused the same 11 participants. The older running trial tested one device, not every cooling method. Ultra performance and heat-illness prevention remain unestablished. No product or cooling schedule is recommended.
Supports preserving the current context-dependent heat guidance and checking the actual performance outcome before adopting a cooling device. The older negative study is a foundation, not a new October trial: https://pubmed.ncbi.nlm.nih.gov/23444094/.
PubMed / primary full text (opens in a new tab) Sleep and readiness: what can the signals tell us? 30 October 2026 · Two reviews put sleep and readiness signals in context. Neither supplies a universal score or sleep target. Existing ultra guidance stays unchanged.
Systematic review, assessed from the primary structured abstract · 2026-10-24
Conceptual Frameworks and Assessment of Readiness to Train in Endurance Exercise: A Systematic Review. Source verification: checked. Read the source audit
A systematic review of 14 endurance studies found inconsistent definitions and varied tools for readiness to train. Many tools measured fatigue, recovery or adaptation rather than directly predicting performance; predictive ability was limited or not assessed.
Limitations: Primary abstract only; full methods were unavailable. Total participant count, sex distribution, study durations and study-level bias could not be verified. Eligibility was 18–65 years, not a verified sample-age distribution. Tool categories overlapped. Validation of a proprietary or combined score, individual clearance rule or ultra-specific cutoff was not available for this appraisal.
Supports the existing distinction between a signal, how recovered you feel and a training decision. It does not establish that monitoring is useless or validate an automatic score-based decision. Existing guidance and numeric planning examples are unchanged.
PubMed / primary structured abstract (opens in a new tab) Systematic review, assessed from the primary structured abstract · 2026-10-28
Sleep Strategies and Performance Outcomes in Ultramarathon Runners: A Systematic Review. Source verification: checked. Read the source audit
A review of 9 studies involving 2262 ultramarathon participants associated greater pre-race sleep with faster finish times. Greater intra-race sleep was associated with longer finish times; the review notes extra nonmoving time and greater sleep needs in longer events. These observational findings do not establish a benefit from changing sleep or show that sleeping less improves race performance.
Limitations: Primary abstract only; full text was unavailable. Review searches ended 25 July 2025. Sex, age, terrain and event/stage durations were not reported in the abstract; the authors’ low-risk-of-bias description was not independently checked. Association is not causation. No pooled time benefit or sleep schedule was available, and equal evidence coverage across ultra distances cannot be inferred.
Supports retaining existing sleep-opportunity and overnight-rest planning. It supplies no nap dose, sleep-loss practice or causal performance promise; duration, overnight exposure, rest access and stage format still matter.
PubMed / primary structured abstract (opens in a new tab) 
