Skip to content

Caffeine increases strength and power performance in resistance-trained females during early follicular phase.

PMID 32681596 (2020): caffeine — Time-trial performance, Time to exhaustion (study note for endurance athletes).

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

Study note • PMID 32681596

Caffeine increases strength and power performance in resistance-trained females during early follicular phase.

Scandinavian journal of medicine & science in sports2020 • DOI 10.1111/sms.13776
Evidence B73/100
Action 2: Consider

Worth trying if it fits your goal and context.

ELI5

In plain language

The effects of 4 mg.kg(-1) caffeine ingestion on strength and power were investigated for the first time, in resistance-trained females during the early follicular phase utilizing a randomized, double-blind,… (randomized trial; n=3 trained athletes).

The abstract doesn’t indicate a clear change in Time-trial performance, Time to exhaustion 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: The effects of 4 mg.kg(-1) caffeine ingestion on strength and power were investigated for the first time, in resistance-trained females during the early follicular phase utilizing a randomized, double-blind,…
  • The abstract doesn’t indicate a clear change in Time-trial performance, Time to exhaustion under the tested conditions.
  • Population: n=3 trained athletes.
  • Protocol cues (title/abstract): 4 mg • 60 minutes • 72 hours.

Protocol

Protocol (as reported)

  • Intervention/exposure: caffeine (vs placebo).
  • Dose/time/duration cues in abstract/title: 4 mg • 60 minutes • 72 hours.
  • Outcomes: Time-trial performance, Time to exhaustion.
  • 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=3 trained athletes) working on supplements.
  • Athletes who can measure Time-trial performance, Time to exhaustion 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 (double-blind, placebo-controlled).
  • Population: n=3 trained athletes.
  • Comparator: placebo.
  • Outcomes measured: Time-trial performance, Time to exhaustion.
  • Protocol cues mentioned: 4 mg • 60 minutes • 72 hours.
  • Source: PubMed PMID 32681596 (2020) — Scandinavian journal of medicine & science in sports.

Results excerpt

What the abstract reports

Caffeine significantly improved squat (4.5 +/- 1.9%, effect size [ES]: 0.25) and bench press 1RM (3.3 +/- 1.4%, ES: 0.20), and squat (15.9 +/- 17.9%, ES: 0.31) and bench press RTF (9.8 +/- 13.6%, ES: 0.31), compared to placebo.

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