Fine motor skills, which use dexterity and hand/eye coordination to perform precise movements (accurate shooting, for example) disintegrate at 115 heartbeats per minute. Complex motor skills, which help muscle groups perform a series of blunt movements (kicks and punches, for example) disintegrate at 145 heartbeats per minute. But most hand-to-hand combat causes the heart to surge to 200 beats per minute. In that frenzy of adrenaline, the combatant becomes one of two large furious deadly animals charging one another.