His capacity for physical strength is potentially limitless due to the fact that the Hulk's strength increases proportionally with his level of great emotional stress, anger in particular. The Hulk uses his superhumanly strong leg muscles to leap great distances. The Hulk has been known to cover hundreds of miles in a single bound and once leaped almost into orbit around the Earth. The Hulk can also use his superhumanly leg muscles to run at super speeds, although his legs have limitless strength he does not have limitless speed and once he reaches a certain speed his legs become too strong and destroy the ground giving him no friction to run on, therefore he jumps to travel. The Hulk can slam his hands together creating a shock wave, this shock wave can deafen people, send objects flying and extinguish fires. His thunderclap has been compared to hurricanes and sonic booms.