Study note • PMID 34334774
Superior On-Ice Performance After Short-Interval vs. Long-Interval Training in Well-Trained Adolescent Ice Hockey Players.
Low risk + high feasibility for most athletes.
ELI5
In plain language
Ronnestad, BR, Haugen, OC, and Daehlin, TE. (randomized trial; n=9 well-trained participants).
The abstract doesn’t indicate a clear change in VO₂max 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: Ronnestad, BR, Haugen, OC, and Daehlin, TE.
- • The abstract doesn’t indicate a clear change in VO₂max under the tested conditions.
- • Population: n=9 well-trained participants.
- • Protocol cues (title/abstract): 9 weeks • 5 minutes.
Protocol
Protocol (as reported)
- • Intervention/exposure: aerobic, endurance (vs comparison group).
- • Dose/time/duration cues in abstract/title: 9 weeks • 5 minutes.
- • Outcomes: VO₂max, Lactate threshold.
- • Replication note: abstracts often omit adherence and timing; confirm details before changing training or supplementation.
Fit
Who it helps, and who should skip it
Who it helps
- • Athletes similar to the study population (n=9 well-trained participants) working on endurance.
- • Athletes who can measure VO₂max, Lactate threshold with a repeatable workout or time-trial effort.
Who should skip
- • 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=9 well-trained participants.
- • Comparator: comparison group.
- • Outcomes measured: VO₂max, Lactate threshold.
- • Protocol cues mentioned: 9 weeks • 5 minutes.
- • Source: PubMed PMID 34334774 (2021) — Journal of strength and conditioning research.
Results excerpt
What the abstract reports
“No significant differences were observed between SIs and LIs in change of maximal oxygen uptake (SI: 3.8 +/- 6.1% vs.”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations & 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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