Skip to content

Effects of Heat Acclimatization, Heat Acclimation, and Intermittent Exercise Heat Training on Time-Trial Performance.

PMID 34706597 (2022): heat acclimation, heat acclimatization — Performance in heat (study note for endurance athletes).

Last updated/Feb 23, 2026, 10:34 PM

Study note • PMID 34706597

Effects of Heat Acclimatization, Heat Acclimation, and Intermittent Exercise Heat Training on Time-Trial Performance.

Sports health2022 • DOI 10.1177/19417381211050643
Evidence C60/100
Action 2: Consider

Worth trying if it fits your goal and context.

ELI5

In plain language

BACKGROUND: The purpose of this study was to investigate effects of heat acclimatization (HAz) followed by heat acclimation (HA), and intermittent heat training (IHT) on time-trial performance. (controlled study; athletes).

The abstract suggests a positive effect on Performance in heat 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: BACKGROUND: The purpose of this study was to investigate effects of heat acclimatization (HAz) followed by heat acclimation (HA), and intermittent heat training (IHT) on time-trial performance.
  • The abstract suggests a positive effect on Performance in heat under the tested conditions.
  • Population: athletes.
  • Protocol cues (title/abstract): 10 days • 5 days • 4 weeks • 8 weeks • 60 minutes • 2.51 minutes.

Protocol

Protocol (as reported)

  • Intervention/exposure: heat acclimation, heat acclimatization (vs comparison group).
  • Dose/time/duration cues in abstract/title: 10 days • 5 days • 4 weeks • 8 weeks • 60 minutes • 2.51 minutes • 3.06 minutes • 3.12 minutes.
  • Outcomes: Performance in heat.
  • 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 (athletes) working on heat.
  • Athletes who can measure Performance in heat 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: controlled study.
  • Population: athletes.
  • Comparator: comparison group.
  • Outcomes measured: Performance in heat.
  • Protocol cues mentioned: 10 days • 5 days • 4 weeks • 8 weeks • 60 minutes • 2.51 minutes • 3.06 minutes • 3.12 minutes.
  • Source: PubMed PMID 34706597 (2022) — Sports health.

Results excerpt

What the abstract reports

Percentage change in time trial was faster in IHT(MAX) (-3.9% +/- 5.2%) compared with IHT(CON) (11.5% +/- 16.9%) (P = 0.020) and approached statistical significance with large effect (effect size = 0.96) compared with IHT(MIN) (1.6% +/- 6.2%; P = 0.059) at post-IHT8.

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.

Coaching beta

Get a plan that adapts to your life.

Join the 26weeks.ai TestFlight beta for adaptive coaching, recovery-aware adjustments, and race-week reminders.

Keep going

Sources