A really interesting article about pain in the magazine Wonderpedia explains how movement can help reduce pain.
Movement against pain
Researcher at University College London discovered that the somatosensory cortex also processes body movement and position. This means that when somebody chafes a wound and also crosses their arms or taps their foot, so much information arrives in the brain at once that the pain signals have competition and lose their intensity.
Source – Wonderpedia Magazine April 2014
This seems to make sense, I picture somebody who has burnt their hand and are jumping up and down waving it in the air. Looking at the UCL research I can really see how this reaction could be helping with that initial pain.
The article continued its reference to the UCL study:
An unusual arm or leg position can confuse your brain so much that it actually masks pain in your extremities. The experiment was conducted at University College London and found that participants with crossed arms were markedly more resistant to pain than those in a normal position. The research team concluded that the irregular limb position inhibits the transmission of painful stimuli
So next time you hurt yourself why not crossing your arms or jumping up and down, it has to be worth a try.