Singh · Cell reports. Medicine 2022 · randomized placebo-controlled trial · n=?

Urolithin A improves muscle strength, exercise performance, and biomarkers of mitochondrial health in a randomized trial in middle-aged adults.

Level 2 - randomized trial

Individual randomized, placebo-controlled clinical trial

PubMed 35584623 · doi:10.1016/j.xcrm.2022.100633 · record verified 2026-08-26

What was done

Middle-aged adults were enrolled in a randomized, placebo-controlled trial (NCT03464500) evaluating oral administration of the mitophagy activator Urolithin A (Mitopure) at two doses over 4 months. Assessed outcomes included muscle strength, peak power output (primary endpoint), aerobic endurance (peak VO2), physical performance (6-minute walk test), plasma biomarkers (acylcarnitines, C-reactive protein), and skeletal muscle expression of proteins linked to mitophagy and mitochondrial metabolism.

What was found

Urolithin A intake led to a statistically significant ~12% improvement in muscle strength, alongside reported improvements in peak VO2 and the 6-minute walk test. The primary endpoint, peak power output, showed no significant improvement. Plasma acylcarnitines and C-reactive protein were significantly lower, and skeletal muscle expression of mitophagy and mitochondrial metabolism proteins was significantly increased. Specific numerical values for sample size, doses, and secondary endpoint effect sizes were not reported in the abstract.

Why it matters

This study provides randomized human clinical evidence that pharmacological activation of mitophagy via Urolithin A can enhance mitochondrial biomarkers and certain functional muscle measures in middle-aged individuals.

Limits

The abstract omits sample size (n), precise dosing values, and numerical data for most clinical endpoints. Crucially, the intervention failed to achieve statistical significance on its prespecified primary endpoint of peak power output.