InHouse Ultra

InHouse Ultra

InHouse Ultra is an indoor, last-one-standing treadmill event held inside Run Unlimited and Twenty One Run in St. Petersburg, Florida. Entry is limited to 33 athletes nationwide. The format requires competitors to complete 5 miles every hour, on the hour, repeating rounds until only one athlete remains.

Rules require each five-mile segment to be finished before the next round begins; missing a round results in a DNF. Athletes may not stack miles and may not stand on the side of a treadmill while the belt is moving. Participants must be self-supported for fuel and gear. One crew member is allowed per athlete but may not provide assistance during treadmill sessions. A recovery zone is available between rounds.

The event space is temperature controlled to 72 degrees. Movies and music will rotate during the event. Athletes are advised to bring a personal chair and cooler for specific nutrition needs. Family and friends may attend to cheer, though studio space is limited. A mandatory check-in is required before the event begins. The venue address is Run Unlimited, 2232 2nd Ave S, St. Petersburg, FL 33712. Visit the organization's website for the most recent information.