Converts a significant percentage of slow-twitch muscle fibers to fast-twitch Type IIx fibers, dramatically increasing explosive speed, reaction time, and sprint velocity at the cost of endurance. Users gain 40–80% improvement in burst speed and 20–30% improvement in reaction time. The modification makes the user startlingly fast in short bursts but exhausts them rapidly — a sprinter, not a marathon runner. The conversion affects all skeletal muscles, including those controlling eye movement and fine motor tasks, resulting in faster visual tracking and quicker hand-eye coordination. Zheng-Dao Bioelectric's version includes fatigue-buffer genes from hummingbirds that extend the duration of peak performance from seconds to minutes. The modification is popular among couriers, fighters, and anyone whose survival depends on being faster than the other person.