The sun had stolen below the horizon, leaving dozens of weary warriors to continue their race bathed in artificial light. I’d watched from the margins as the energy and enthusiasm they’d exhibited at the start had slowly drained from their exhausted bodies, and after 18 hours, each new circuit of the track edged the group toward further despondency. Despite the uniqueness of the challenge and the camaraderie shared by the runners, I was relieved not to be among them. Instead, I embraced my role as a one-man support crew. Camped on a grassy area near the start/finish line, cloaked in the kind of frosty air that only flourishes in the dead of night, I turned to my coffee and notepad—my only semblance of civility in the madness we’d all accepted as normal.
When the clock had eventually run down, the overall winner was a man in his early 40s. But the bulk of the plaudits went to the first-place female: a record-breaking, 68-year-old grandmother who’d rounded the track 467 times and clocked up 116 miles. I’d watched in awe for 24 hours as she’d marched down men and women half her age with relentless vigor, her slight frame bent at the waist propelled by thickset legs that may as well have been mechanical pistons. On another day, in another place, she was a mother, grandmother and friend—just little old Ann. On that track, she was a force of nature, growing in strength and spirit as those around her faded.
Such inspirational performances from “aging” athletes are rare in any sport but less so in ultrarunning. Documented trends show that the age of peak performance increases with the race distance, from 100 miles to the longest of ultras. That makes ultrarunning an option for many runners long after they’d have retired from more conventional and less arduous contests.
Look at track and field events, especially sprinting and throwing. Success depends largely on explosive power—generating as much force as possible and channeling it through carefully refined technical skills. This coordination between the nervous system and the skeletal muscles, so-called neuromuscular efficiency, becomes highly developed by the mid-20s, hence the average age of peak performance in these events (1).
In standard “endurance” sports, from 1,500 meters to the marathon, performance depends less on explosive power and more on sustainable power, underpinned by aerobic metabolism—that is, the efficient use of oxygen. In fact, 90-95% of the variability in marathon performance can be predicted with just three laboratory-based metrics: maximal oxygen uptake (VO2max), lactate threshold and running economy (2). Physiologically, aerobic endurance hangs around longer than explosive power, so the range of peak performance in marathon running tends to be broader, between 25 and 35 years (3).
In ultrarunning, athletes reach their physical peaks later than in any other sport. That was the conclusion of a large study from researchers in Switzerland who analyzed data from nearly 100,000 time-limited ultramarathons that took place between 1975 and 2013. In 6-hour events, the average age of peak performance was 33.7 years, with the true range being 32.5 - 34.9 years. In 48-hour events, peak performance occurred at 46.8 years (46.1 - 47.5 years), and in races lasting longer than 48 hours, athletes reached their peaks in the mid-40s or early 50s (4,5).

What underpins greater longevity in ultrarunning?
Ultrarunning is marathon’s more enigmatic older sibling. Unlike the 42.2k distance, there’s no magic formula to success in ultras, nor can we explain performance with a convenient set of metrics. Aerobic metabolism, of course, plays a role, but VO2max is considerably less important with as race distance increases (6,7), at which point other factors become more performance-limiting. Anybody who’s ever sullied their sneakers in a relatively long ultra (say, more than 50 miles) will have firsthand experience of the various difficulties: managing nutrition, maintaining gut function, mitigating muscle damage, avoiding injury, needing to reach repeatedly into the depths of their souls in search of the dogged determination they need not to give up when the wheels fall off. All these factors are heavily influenced by experience and temperament and are usually seasoned by the years. That’s why performance in any given race is significantly related to the number of previous race finishes (4).
But only to a point. In ultrarunning, experience may be your closest ally, conferring an advantage against younger runners, but eventually, the scales will be tipped by the ever-falling sands of time. When does that happen?
For non-elites, individual performances typically drop off once you hit your 50s, with variability based on genetics, training and nutrition history, family history and sociocultural factors. Menopause is a wildcard. Typically occurring between 45 and 55 years old, it brings with it new challenges in an already challenging sport: changes in hormonal status, substrate efficiency and injury risk, all affecting the average age of peak performance in females.
None of this means that ultrarunners should hang up their trail shoes when they reach their 50s. On the contrary, many ultrarunners continue racing into their late 70s (8) and occasionally, we even encounter a treasure like little old Ann. It simply means that, as we age, we must give more consideration to how we train, how we recover, and how we plan to maintain running longevity into the future.
Age like Wine, Not Fruit
The year after witnessing Ann’s inspiring performance on the track, I was back in my trail shoes, taking on England’s green and domesticated countryside in a 3-day east-to-west footrace. It was my second time at the event, and I still had no reverence for the frigid air or the trails that’d been turned the consistency of pancake batter by relentless rain. Still, I’d remained in the top 10 as other runners dropped off the pace. Mingled with the white noise of rain on leaves, I heard a set of plodding footsteps at the rear. As the old guy passed me, I first noticed his mop of silvery hair and then the red backpack strapped across his naked torso—something conspicuous at any time of year, but more so in the freezing temperatures.
“What happened to your shirt?” I asked, a little confused.
“I tend to run hot,” he yelled over his shoulder with a well-spoken, upper-class intonation, “I usually start my races like this. It saves time.”
In the hours that followed, we played proverbial tag on the trails, exchanging positions and broken conversation. He was a solid runner for an old chap, not easy to shake, and his eccentric mannerisms made him enjoyable company with whom to while away some time on the trail. I found out some days later I’d been talking with Sir Ranulph Fiennes—the renowned British explorer and adventurer known for his record-breaking expeditions to Earth’s most extreme environments. Fiennes was 72 years young when I met him. He was training to compete in the Marathon Des Sables the following year.
Fiennes is known in part for his ageless endurance—he became the oldest Briton to summit Everest at the age of 65. But in a 2016 interview with the Evening Standard newspaper (UK), he admitted to being stalked by the shadows of time:
“I look back on my adventures only to think it would be nice to think that I was still able to achieve like I did. Which it is not. Even in 2009 I could cope with big falls. You just look at yourself in a different light, you know, geriatric… It’s a real nuisance growing older. What it means is I have to really try my hardest to counteract it.”
Few people are fortunate enough to have Fiennes-esque longevity, and even the man himself admits he’s been blessed with a healthy dose of good luck. But assuming you’re not endowed with unassailable genetics, what recourse do you have to extend longevity in this arduous sport?
Focus on Reducing Your Risk of Musculoskeletal Injury
Hundreds of studies have examined the predictors of injury risk in runners. There’s no unequivocal signal, but older age tends to confer greater risk (9). You probably already know the basics of reducing injury risk: get adequate rest between workouts, especially after threshold, interval or other “hard” sessions. Don’t train while sore and vary your running surface to include relatively more trail, grass and treadmill (i.e., surfaces that give underfoot). Allow extra time for musculoskeletal adaptations by avoiding sharp increases in mileage, and replace your sneakers when they become worn. There are a few lesser-known strategies for minimizing injury risk. Try doing any interval or speedwork uphill (at a gradient range of 4-12%) instead of on the flat—it’ll evoke the necessary oxygen uptake without the same impact stress (10). Moreover, it’s never too late to engage in a strength training program as long as it’s tailored to your individual abilities. The National Institute on Aging takes a “use it or lose it” approach to strength training, advocating resistance exercise for older adults to reduce injury risk and improve quality of life (11).
Stop Fighting Your Physiology
There’s a natural, age-related decline in fitness. It’s driven mainly by maximal oxygen uptake, which falls by 1-2% every year after age 30. This is initially due to diminished cardiovascular capacity and later by peripheral factors like the ability of the muscles to fully utilize the oxygen they receive (12). You have a choice to make in the face of this inevitable truth. Your first option is to train harder, spend more time doing intervals and fight tooth and nail to retain your top-end fitness. This may work for a while, but it’s an exercise in diminishing returns—becoming more difficult with each passing year and requiring a lot of effort with little payoff. It may also increase your injury risk. The alternative is to redirect your efforts to training those aspects of your physiology over which you have greater control and which may confer greater performance benefits. As mentioned, maximal oxygen uptake isn’t as important for long ultras as we used to think (6,7), whereas running economy, lactate threshold and peripheral conditioning (13) can all be better maintained or even improved well into older age. So, pick your battles.

Refine Your Recovery
The recovery triarchy has reigned supreme over athletes for centuries and includes good rest, nutrition and sleep. If you’ve lasted this long in ultrarunning, chances are you’ve implemented this system quite well. But aging brings with it all kinds of unpredictable bodily changes. Chief among them is something called anabolic resistance—a decreased sensitivity to the amino acids you eat and a subsequent reduction in muscle protein synthesis (14). This has major implications for repairing damaged muscles and largely explains why aging brings delayed, prolonged and inefficient recovery from training and racing. This is one battle worth contesting. Counter the age-related decline in anabolic signaling by eating more high-quality protein (i.e., that contains leucine) and making sure you meet your daily protein needs of 1.2-1.4 grams per kilogram (15). Protein isn’t a cure-all—all the steak and whey in the world won’t get you back on the trails before you’re adequately rested. So, be prepared to take additional time between hard sessions and, above all, listen to your body. While you’re at it, pull the plug on ice baths: they suppress muscle protein synthesis and will hinder rather than help your recovery (16).

Kick the Tires Before Taking a Long Drive
How long a car can continue to run smoothly depends on many factors: the solidity of its construction, how well it’s cared for and maintained, and how many miles are on the clock. Before going on a long drive, it’s prudent to check the tire pressure and the oil and ensure there’s enough fluid in the radiator. This becomes more vital as it ages. We’d all probably agree that taking these basic precautions increases the vehicle’s longevity. Why should your body be any different? When you spend years contesting races that are hundreds of kilometers, it’s easy to normalize the absurdity when, in fact, ultramarathons are about as extreme as a sport can be. The physical and psychological strain is enormous. It’s vital that we take basic precautions like staying on top of simple health metrics (e.g., cholesterol, blood sugar, blood pressure), being familiar with family history to determine relative disease risk, following up on any symptoms, and checking in with your doctor so they can clear you to keep racing. Too many runners have had to hang up their trail shoes early because they ignored signs of wear and tear, allowed niggles to degrade, bones to become brittle or cardiovascular health to decline. If your car breaks down, you might be able to get a new one: that’s where this analogy ends.
So, how old is too old for ultrarunning? It’s true that training and racing don’t get any easier as we age and add miles to the counter. But assuming you periodically kick the tires, mitigate your injury risk and stay on top of wear and tear, you’re never too old to contest this weird and wonderful sport for as long as you feel able. And with hard work and a little of Fiennes’ good luck, who knows—there’s even a chance you’ll be breaking records into your 60s and 70s.
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