Study note • PMID 25756657
Smartphone-Derived Heart-Rate Variability and Training Load in a Women's Soccer Team.
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: controlled study.
- • Population relevance: mixed/unclear athlete specificity.
- • Consistency: single-study evidence.
- • Practical recommendation depends on tolerance, context, and whether it protects training consistency.
ELI5
In plain language
This study evaluated the 7-d mean and coefficient of variation (CV) of supine and standing ultrashort log-transformed root mean square of successive R-R intervals multiplied by 20 (lnRMSSDx20) obtained… (controlled study; participants).
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: This study evaluated the 7-d mean and coefficient of variation (CV) of supine and standing ultrashort log-transformed root mean square of successive R-R intervals multiplied by 20 (lnRMSSDx20) obtained…
- • The abstract doesn’t indicate a clear change in Recovery speed under the tested conditions.
- • Population: participants.
- • Protocol cues: abstract may omit dose/timing; use the full paper to replicate accurately.
Protocol
Protocol (as reported)
- • Intervention/exposure: smartphone, derived (vs comparison group).
- • Dose/time/duration: abstract doesn’t include enough detail; use the full paper’s methods section.
- • 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 (participants) working on monitoring.
- • 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: controlled study.
- • Population: participants.
- • Comparator: comparison group.
- • Outcomes measured: Recovery speed.
- • Source: PubMed PMID 25756657 (2015) — International journal of sports physiology and performance.
Results excerpt
What the abstract reports
“The 7, 5, and 3-d supine CV and the 7-day standing CV were moderately lower during the low-load than the high-load week (P .003-.045, effect sizes 0.86-0.92), with no significant changes occurring in the other measures.”
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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