At 65, Susannah Dyson, an electrical engineer from the Indianapolis area, ran more than 66 miles during a recent backyard ultramarathon, highlighting the growing popularity of this demanding race format. The event, known as Prairie on Fire, took place outside Indianapolis and required participants to complete a 4.167-mile loop every hour. Runners must finish each loop within the hour or face elimination, with the last person remaining declared the winner. Dyson’s pace was slower than typical marathons, but endurance and strategy, rather than speed, are central to these races.

Backyard ultramarathons typically extend beyond 100 miles and often run continuously over several days. The format has seen significant expansion; in the past year, at least 500 backyard ultras were held worldwide, with more than 700 scheduled for the coming year. Events are organized in various locations, including parking lots and trails across the United States and about 80 other countries.

Prairie on Fire attracted hundreds this year, starting with a few hundred runners, many local, who camped on site with friends and family providing support. Throughout the event, runners rested between laps, either napping or preparing for the next loop. Dyson described the event as bringing “a nice feeling of accomplishment,” even if participants anticipated soreness afterward.

The backyard ultramarathon concept was created in 2011 by Gary Cantrell, also known as Lazarus Lake, who is famous for founding the Barkley Marathons, a notoriously difficult ultrarun. Cantrell designed the backyard ultramarathon format to fit on his 140-acre farm, beginning with a casual first race. He noted the format’s unexpected surge in popularity. Its appeal lies in the manageable pacing requirement—the cutoff time for each loop is slower than many marathon paces—allowing runners to push themselves for extended periods. The hourly restart also fosters a social atmosphere, differing from ultramarathons where participants are often isolated.

TJ Dailey, organizer of Prairie on Fire, said the simplicity and compact nature of backyard ultras make them easier to stage than traditional ultramarathons, which often require complex logistics through challenging terrain. The simplicity proved advantageous during the COVID-19 pandemic when socially distanced virtual events were more viable.

Participants employ a mix of running and walking, balancing energy expenditure with rest between laps. Competitors consume high-carbohydrate drinks and comfort foods while managing aches and injuries, with some tapering stimulants like caffeine and avoiding painkillers to remain attuned to their bodies. Carly Trulock-Quinn, a competitor who withdrew before reaching her goal due to pain, emphasized the risks of overexertion common in the ultrarunning community.

At Prairie on Fire, Majel Wells, 48, covered 129.1 miles, becoming the last woman standing, while the overall winner, Matthew Sandlin, 42, completed 179.1 miles before finishing the race early Monday morning. Sandlin described the challenge as an expression of personal grit and faith beyond his everyday life, noting that he was prepared to continue running indefinitely when others had dropped out.

The backyard ultramarathon tests physical and mental limits in a unique, community-based endurance event, with the winner determined by who can endure the longest in this repetitive, grueling format.