Digestery
Longevity supplements › Urolithin A and Muscle › Studies

Randomized trial · measured other health measures

4-week trial in 42 runners: no clear gain in 3000 m time trial

Whitfield and colleagues · Sports medicine (Auckland, N.Z.) · 2025

Original title: Evaluating the Impact of Urolithin A Supplementation on Running Performance, Recovery, and Mitochondrial Biomarkers in Highly Trained Male Distance Runners.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

No difference

The 3000 m time trial did not improve in either group (UA p = 0.116, placebo p = 0.771). Aerobic capacity gain did not differ between groups (p = 0.138). Muscle damage marker CK was lower with UA (p < 0.0001).

The study at a glance

Type of study
Randomized trial
Who or what was studied
42 people · 42 young, highly trained male distance runners at an altitude camp
What was tested
1000 mg urolithin A a day for 4 weeks, vs placebo
What it measured
Several kinds of outcomes
Daily amount
1000 mg a day
How long
4 weeks
Trial registration
NCT04783207
Who has a stake
Company stake
Amazentis SA, maker of Mitopure (urolithin A), sponsored and funded the study; three authors are its employees and one got its travel support.
Journal
Sports medicine (Auckland, N.Z.), 2025
Source
PubMed record 40839339. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • ✓Compared with a placebo, a dummy treatment.
  • –Small: 42 people. Small trials can miss real effects or find chance ones.
  • –Short: 4 weeks. Longer-term effects are unknown.
  • •Measured several kinds of outcomes.
  • –Company stake: Amazentis SA, maker of Mitopure (urolithin A), sponsored and funded the study; three authors are its employees and one got its travel support.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: muscle strength and endurance

    0

    Not done yet. This is the step that would answer the question.

  2. Trials in people: other measures

    4

    3 mixed, 1 no difference

    ↑ This study is the ringed dot

  3. Trials in people: lab tests or safety

    0

    None among the papers we read.

  4. Population studies

    0

    None among the papers we read.

  5. Blood levels and genes

    0

    None among the papers we read.

  6. Animals

    2

    2 benefit

  7. Cells in a dish

    1

    1 no direction

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Does urolithin A improve muscle health with age?”

Unclear: small trials, mixed results.

Confidence: very low. Based on 9 on-topic papers.

Read the full answer

Of the other 3 papers on the same step: 3 mixed. This one found no difference. It differs from most of them.

  • Quoted in “What we found”: Four placebo-controlled trials in people tested urolithin A on muscle: two in middle-aged or older adults (one with 66 people) and two in trained male athletes (20 and 42).
  • Quoted in “What we found”: Three trials gave 1000 mg (1 g) a day; one compared two doses with placebo. Trials lasted from 4 weeks to 4 months.
  • Quoted in “What we found”: Three of the four trials had employees of Amazentis SA, maker of Mitopure, among their authors. Amazentis sponsored two of them.
  • Part of the finding “No race gain in trained runners”.
  • Part of the finding “Markers moved, but energy output did not”.
  • Marked as a key paper in the research timeline: Elite runner trial: no race time gain.
  • Open item for a person: Whitfield 2025 (young runners) and Pierre 2025 (sepsis mice) are indirect for aging; kept relevant because they test urolithin A on muscle.

Other papers on the same step

See all 9 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The reviewer corrected 2 fields after reading the abstract. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
Not yet. Required before search engines may list this page.

Spot an error? Email a flag with a link to your source, or use the form on the question page.