Study note • PMID 33870188
Effect of the Depth of Cold Water Immersion on Sleep Architecture and Recovery Among Well-Trained Male Endurance Runners.
How to use this page
This note summarizes one study record. Check the participants, methods, results, and limitations before applying it to training.
- • Design signal: randomized trial.
- • Population relevance: athlete/trained context.
- • Consistency: single-study evidence.
- • Practical recommendation depends on tolerance, context, and whether it protects training consistency.
ELI5
In plain language
Introduction: The aim of the present study was to investigate the effect of the depth of cold water immersion (CWI) (whole-body with head immersed and partial-body CWI) after high-intensity,… (randomized trial; n=12 well-trained runners).
The abstract doesn’t indicate a clear change in Recovery speed under the tested conditions. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: Introduction: The aim of the present study was to investigate the effect of the depth of cold water immersion (CWI) (whole-body with head immersed and partial-body CWI) after high-intensity,…
- • The abstract doesn’t indicate a clear change in Recovery speed under the tested conditions.
- • Population: n=12 well-trained runners.
- • Protocol cues (title/abstract): 10 min • 48 h • 80 min • 180 min.
Protocol
Protocol (as reported)
- • Intervention/exposure: cold water immersion, recovery (vs control condition).
- • Dose/time/duration cues in abstract/title: 10 min • 48 h • 80 min • 180 min.
- • Outcomes: Recovery speed.
- • Replication note: abstracts often omit adherence and timing; confirm details before changing training or supplementation.
Fit
Who it may help, and who should be cautious
Who it helps
- • Athletes similar to the study population (n=12 well-trained runners) working on recovery.
- • Athletes who can measure Recovery speed with a repeatable workout or time-trial effort.
Who should be cautious
- • If you have symptoms or conditions that make the intervention risky, get professional guidance.
- • If you’re near race day and can’t safely test, defer the experiment.
Methods
What the study actually did
- • Design: randomized trial.
- • Population: n=12 well-trained runners.
- • Comparator: control condition.
- • Outcomes measured: Recovery speed.
- • Protocol cues mentioned: 10 min • 48 h • 80 min • 180 min.
- • Source: PubMed PMID 33870188 (2021) — Frontiers in sports and active living.
Results excerpt
What the abstract reports
“Slow-wave sleep (SWS) proportion was higher (p < 0.05) during the first 180 min of the night in WHOLE compared with PARTIAL.”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations and bias
- • Abstract-only summaries can miss critical details (population, protocol, adherence, and context).
- • Single studies often don’t generalize to your event, history, and training load; treat results as a starting point.
- • If your context differs (elite vs recreational; cycling vs running), adjust expectations and be conservative.
- • This is performance information, not medical advice.
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