What was the method of the record holder for standing on one leg?

The method of the record holder for standing on one leg was to balance without resting. This describes the skill and endurance required to maintain a standing position on one leg for an extended period, showcasing physical balance and strength. Successfully achieving this record would necessitate continuous engagement of muscles and focus to avoid falling, making balance crucial to the endeavor. The option reflects the essence of the challenge, emphasizing the difficulty and physicality of maintaining a single-leg posture for a long duration.

The other options do not align with the nature of the record. Resting a leg against another or taking breaks would undermine the integrity of the challenge, while sitting would nullify the requirement to stand on one leg entirely. Therefore, maintaining a balanced position without any rest is the correct and definitive method to achieve this particular record.