Although marathoning and ultramarathoning may sound similar, the shift from one to the other is anything but transparent.
Marathons are typically run on paved roads, whereas ultramarathons can span across a variety of terrains, demanding a shift in focus from pure aerobic power to energy management and technical skill. While a road marathoner’s aerobic engine and running economy provide a strong foundation, navigating nutrition, gear and uneven terrain becomes critical for an ultra.
2020 Olympic marathon medallist Molly Seidel is one athlete making the jump from the road to the trails. After competing in this year’s TCS New York City Marathon on Nov. 2, she is set to compete at the Black Canyon 100K in February 2026. With the change in distance comes a major shift in training as well, now guided by American ultrarunning coach Cliff Pittman.
In an interview with TrainingPeaks, Pittman shared some tips and insights into how he is helping the 31-year-old 2:23 marathoner prepare for her first ultra.
Don’t treat an ultra like a long marathon
According to Pittman, the biggest mistake he sees beginners make in ultrarunning is approaching it as just an extended marathon.
“Marathoners can often get away with mild dehydration or underfueling, but in an ultra, these mistakes can have catastrophic consequences,” he said. “Additionally, the gear and terrain at these races can significantly alter biomechanics and muscular load. Becoming familiar with these elements is critical for performance in longer events.”
For Seidel, her training plan gradually integrates these aspects so that when she lines up at Black Canyon 100K, nothing feels foreign.
Keep building on your strengths
Seidel has historically excelled on challenging courses and in tough conditions. The Olympic marathon in Tokyo, where she won bronze, was hot and humid, and the 2020 US Marathon Trials in Atlanta, where she finished second, featured a lot of elevation gain.
Pittman said the approach they’ve taken from a marathon to a 100K is rational: focus on threshold training and fatigue resistance. “Her sessions now progress from threshold efforts to sub-threshold paces (e.g., Zone 3 to Zone 5) to improve durability for the long run,” he said. “She is also completing much longer runs, moving from two to three hours on the road to four to five hours on the trails.”
To begin her Black Canyon build, Seidel will tackle longer steady-state efforts, such as 2 × 30 minutes in Zone 3 during long runs. As the race approaches, these efforts will shift to the back end of her runs, training the body to run fast when glycogen is depleted and mental fatigue sets in.
Train for resilience
While speed is valuable, Pittman says ultrarunning depends more on mental resilience than just raw pace. “Success in ultras requires more than talent,” Pittman said. “Runners need to know how to keep pushing when they think they have nothing left, and this is exactly the part of the sport that Seidel seems ready to embrace.”
Researchers and experts often say that running is about 80 per cent mental at the elite level, and for Seidel in particular, handling adversity when things go wrong has long been one of her strengths.
