Sure, ultrarunning is impressive and all. Those 100-mile trail races can be brutal, as Karl Meltzer knows full well. After winning 29 of the 46 he's attempted, he respects the sport's rigors.
So what's beyond "ultra" for an endurance athlete driven to push limits?
Try multiday or, heck, multimonth feats on foot through all terrain and weather. Call it über- ultrarunning, a test of will and sanity.
On Wednesday morning, Meltzer, 42, took off from Old Sacramento on a 45- day, 2,000-mile retracing of the Pony Express for its 150th anniversary. Sponsored by Red Bull energy drink, Meltzer's run will take him over the Rocky Mountains and across the Great Plains – the same general path taken by the Pony Express for 18 months in the 1860s, before it was displaced by the telegraph.