the sugar in the drinks stimulates insulin generation which helps in the use of fat stores for energy not to mention it gives endorphin boost which makes you feel better. Also it helps with recovery, you should drink these drinks about a half hour before working out/training and after. If you drink it before your body will divert blood to the digestive system to digest the sugars/electrolytes which will cause a drop in performance and will slow down the absorbtion of the liquids.