Urolithin A for Hikers

Reviewed by SOMA HEALTH's Medical Research Team

Long trails are an endurance problem before they are anything else. Hour after hour of climbing under a loaded pack asks your muscles to keep making energy long after the novelty wears off. Urolithin A is being studied for exactly this layer of the picture: how efficiently the mitochondria inside working muscle produce and sustain energy.

This guide looks at where the human evidence for urolithin A actually stands, where the research is still early, and how a hiker might think about it honestly. We separate what has been shown in people from what has only been observed in cells and animals, because that distinction matters more than any marketing headline.

Why hikers care about mitochondria

Sustained hiking, especially multi-day travel with elevation and a heavy pack, is dominated by aerobic metabolism. Your slow-twitch muscle fibers rely on mitochondria — the tiny structures that turn fuel and oxygen into usable energy — to keep producing power at a walking cadence for many hours. The healthier and more numerous those mitochondria are, the longer you can hold a steady output before your legs feel heavy and your pace drops. Real-world backcountry fatigue is multifactorial: cumulative load, sleep debt, underfueling, dehydration and terrain all stack up. Mitochondrial quality is only one input, but it is the input urolithin A is designed to address.

Over time, and with repeated hard efforts, some mitochondria become worn out and less efficient. Cells normally clear these damaged units through a recycling process called mitophagy, making room for fresher, better-functioning ones. Urolithin A is being investigated because of its apparent ability to support that cleanup process.

What urolithin A is

Urolithin A is not something found directly in food. It is a gut postbiotic: your gut bacteria produce it from ellagitannins, compounds concentrated in pomegranates, walnuts and some berries. The catch is that only some people carry the right microbial mix to make meaningful amounts, which is why two hikers eating the same trail mix can end up with very different urolithin A levels. Supplementing the finished compound directly sidesteps that lottery. If you want the deeper background, our urolithin A guide and our page on foods high in urolithin A cover the source chemistry in more detail.

The human evidence, from strongest to newest

Established human safety and a mitochondrial signature

The first-in-human study by Andreux and colleagues (Nature Metabolism, 2019) established that urolithin A was safe and well tolerated at single doses up to 1,000 mg per day, and reported a mitochondrial gene-expression signature in muscle consistent with the mechanism seen in the lab. This is foundational: it is why later performance studies could be run at all, and why the 1,000 mg figure recurs.

Muscle endurance and strength in people

In a randomized trial in older adults (Liu, D'Amico and colleagues, JAMA Network Open, 2022), roughly four months of supplementation was associated with improvements in measures of muscle endurance. A separate randomized trial in middle-aged adults (Singh and colleagues, Cell Reports Medicine, 2022), which tested 500 mg and 1,000 mg arms over four months, reported benefits for muscle strength and aspects of exercise performance. For a hiker, muscle endurance — the ability to keep contracting without fading — is the trait that most directly maps onto a long climbing day.

Newer human findings

More recent human work has widened the picture. An eight-week randomized trial in resistance-trained men (Journal of the International Society of Sports Nutrition, 2024) examined urolithin A in already-active people, which is a more relevant population than sedentary volunteers if you are a conditioned hiker. A 2025 trial in distance runners looked at endurance athletes specifically. And a 2025 randomized controlled trial published in Nature Aging reported that about four weeks of urolithin A supported the mitochondrial health of immune cells in midlife adults, part of the emerging research on so-called inflammaging. These are promising and directionally consistent, but they are still a modest body of work with varied designs and endpoints.

What is still preclinical

It is important to be clear about which claims rest only on cells and animals. The original mechanistic work by Ryu and colleagues (Nature Medicine, 2016) showed that urolithin A induced mitophagy, extended lifespan in the worm C. elegans, and improved muscle function in rodents. That study is the reason anyone is interested in urolithin A at all, but worm and rodent results do not automatically transfer to human hikers. Separately, D'Amico and colleagues (Aging Cell, 2022) reported effects on joint and cartilage tissue in osteoarthritis models — relevant-sounding to knees under downhill load, but this is preclinical work in disease models, not evidence that the gummies do anything for your joints. Treat joint, skin, gut, heart and brain claims as early, exploratory research only.

A 2024 systematic review in Ageing Research Reviews on targeting aging with urolithin A in humans summarized the situation fairly: the human evidence is still emerging. That is the honest headline. Urolithin A is a plausible, mechanistically grounded ingredient with a real and growing human dataset for muscle and mitochondrial endpoints — not a finished, settled story.

Practical guidance for hikers

Human studies have used 500 to 1,000 mg per day, with 1,000 mg at the top of that range. Benefits in the trials accrued over roughly four months of daily use, so this is a base-building supplement, not a pre-hike stimulant you take at the trailhead. If you are training toward a big objective, the practical move is to start well before your season, not the week of your trek. Our pages on how long urolithin A takes to work and urolithin A for muscle go deeper on timelines and mechanism.

Urolithin A supports the cellular machinery behind endurance; it does not replace the things that actually build a hiker: progressive mileage, load carriage practice, adequate fuel and sleep, and smart pacing. Think of it as one supporting input inside a training and mitochondrial health plan, layered on top of the fundamentals rather than substituting for them.

A note on your body: mobility, joint and other health concerns are not something a supplement treats. Urolithin A is not a treatment for any medical condition, and nothing here is medical advice. If you have knee pain, a health condition, or you are pregnant, nursing or on medication, talk with your doctor before starting anything new.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This guide is educational and is not a substitute for advice from a qualified healthcare provider.