While performing however, a dilute sugar drink might give you an edge (3-6% solution). Just an odd bit of information, just swishing juice or Gatorade around in your mouth without swallowing will help. Kind of like a fake out (NOTE) on your physical self. Stay hydrated. Dehydration will increase your heart rate and stress level (Logan_Sprenger et al. 2012.) Stay cool as possible. High core and brain temperature and dehydration will slow you down or make you stop.