At a time when “endurance running” no longer means mere marathons — and even 100-mile races are attracting the masses — Karl Meltzer, a former ski-resort bartender, has proved he can suffer longer and faster than almost anyone else.

When he staggered onto Springer Mountain in Georgia before dawn Sunday, Meltzer set a record for completing the Appalachian Trail. He covered the 2,190 miles over 14 states in 45 days 22 hours 38 minutes.

Meltzer, 48, is a little different from other titans of the newly booming ultra-running scene. He is six years older than Scott Jurek, who was featured in the best-selling book about almost-barefoot endurance running, “Born to Run” — and who set the former Appalachian Trail record last year (46 days 8 hours 7 minutes).

In a sport checkered with mantras like “clean living,” Jurek sustained his trek on a vegan diet. Staples of Meltzer’s diet, by contrast, included Red Bull and Tang. Jurek incurred a $500 fine and public outrage for opening champagne at the summit of Mount Katahdin in Maine during his record run. When Meltzer finished Sunday, he walked down the mountain, sat in a chair and sated himself with pepperoni pizza and a beer.

It was the latest milestone in an unusual professional racing career.

Meltzer moved to Utah to ski in 1989 and started running the next year. He came to long-distance racing in his late 20s. Primarily a skier, he worked as a bartender at the Snowbird ski resort but took summers off to run. Now based in Sandy, Utah, he became an ultra runner in 1996 after completing a 100-mile race nearby in just over 28 hours.

In a sport built on comparatives — faster, longer, more, more, more — his 100-mile trail race portfolio is formidable: He has won 38 of them, more than anyone else in the world.

But the Appalachian Trail was a particular challenge. This was Meltzer’s third attempt at the record, and his first since Jurek set it last year. He tried once in 2008, finishing a week off the record; in 2014 he dropped out with 600 miles left.

This time, he capped each night with one or two beers and left from rest stops with rainbow-colored Spree candy, Three Musketeers chocolate bars and bacon in his pockets. To save time and keep his energy up, he typically slept less than seven hours a night and instead had an energy drink every 10 miles, downing about five a day. When on another day his support crew found him napping, they gave him a pint of ice cream for a boost.

Though Meltzer averaged 50 miles in 15 hours of running a day, his pace faltered at times. At one point he slept on the trail instead of making it to his support van — and then he slept the next morning on the dirt again. But in the last two days, he gathered strength, running 83 miles nonstop in the final leg to finish Sunday morning at 3:38.

His support crew said Meltzer was not available for an interview immediately after completing his run. He was sleeping.