The Growing Appeal of Ultra Marathon Running
Ultra marathons—races exceeding the traditional 26.2-mile marathon distance—are experiencing unprecedented growth in popularity. After a quiet Thanksgiving weekend on the ultramarathon race calendar, things heat back up during the first weekend of December, with 55 exciting events scheduled. This surge reflects a broader trend: North American data shows significant participation, with unique runners increasing from 8,403 in 2000 to 97,733 in 2024.
Ultramarathons are run around the world with more than 600,000 people completing them every year. The sport has captured the imagination of runners seeking challenges beyond conventional racing, with participation increasing by 1676% in the last 23 years according to comprehensive race data. What was once a niche pursuit has become a mainstream phenomenon, with ultra-running continuing to surge while participation in 5Ks and marathons has largely leveled off, if not declined in recent years, with the growth rate of ultra-running participation surpassing that of marathons since 2009 and that of 5Ks since 2015.
What Defines an Ultra Marathon
An ultramarathon is a footrace longer than the traditional marathon distance of 42.195 kilometres (26 mi 385 yd). These races vary dramatically in format and distance. The shortest common ultramarathon is 31 miles (50 km), and around 100 miles (160 km) is typically the longest course distance raced in under 24 hours, but there are also longer multiday races commonly held as 48 hours, 200 miles (320 km), or more, sometimes raced in stages with breaks for sleep.
Recent events showcase this diversity. Founded in 1985, the Hunter S. Thompson Fear & Loathing urban ultramarathon is back on the streets of San Francisco for its 41st edition, taking participants on a tour of the city’s major landmarks, including the Golden Gate Bridge, China Town, City Hall and Fisherman’s Wharf. Meanwhile, the PPTC Endurance Fest, organized by Prospect Park Track Club, emphasizes community, accessibility, and inclusive running in NYC, offering a supportive, beginner-friendly ultramarathon experience.
The Health Considerations and Challenges
Ultra marathon running presents unique health considerations that distinguish it from shorter distances. Ultra-marathoners were healthier compared to the general population and less often absent at school or at work, with serious diseases such as cancer (~4.5%), coronary heart disease (~0.7%), strokes (~0.7%), diabetes (~0.7%), and HIV (~0.2%) being very rare.
However, there are many health benefits of participation, and ultra-endurance running rarely evokes serious adverse events, though there is a growing body of evidence suggesting that it may have implications for long-term health, particularly affecting the cardiovascular, respiratory, and musculoskeletal systems. Running, even extremely long distances, can be done with minimal long-term health impacts for most people.
Training requirements are substantial. Ultra-marathoners are older and have a larger weekly training volume, but run more slowly during training compared to marathoners, with previous experience, specific anthropometric characteristics (low body mass index and body fat), and training characteristics (high volume and running speed) being the most important predictor variables for successful ultra-marathon performance.
The Future of Ultra Marathon Running
The ultra marathon movement shows no signs of slowing. Over the last decade, the average age of ultra-runners has dropped by nearly two years as younger participants tackle races beyond the marathon distance. Additionally, women are embracing ultra-running, with just 14 percent of ultra-running participants being female in 1996, but women now representing nearly one-quarter of ultra participants.
For prospective ultra runners, the key message is clear: for those who train smartly, pay attention to their body’s signals, and balance running with rest and recovery, ultra marathons can be a healthy endeavor, however, without proper preparation and awareness, they can pose significant health risks. As this extreme sport continues to grow, it offers both seasoned athletes and newcomers an opportunity to test their limits while joining a supportive global community of endurance enthusiasts.
