About 75 percent of the energy you put into exercise is converted into heat and is then lost. This is why exercise makes you feel warmer. Extra heat has to be dissipated to keep your core body temperature within safe limits – around 37-38°C. Your body keeps cool by sweating, which makes the replacement of fluids crucial. Fail to consume enough fluid, and your blood will thicken, reducing your heart's efficiency, increasing your heart rate, and raising your body temperature.
You need to start a run or race hydrated. By drinking 500ml of fluid two hours before a run – try water, a sports drink, or diluted fruit juice – and another 150ml of fluid just before you run, you'll have enough time for your body to clear what you don't need before you set off.
If you've been running for less than an hour, make sure to be sipping plain water ( not gulping!). If you have been running hard for longer than an hour, drinks containing sugar or maltodextrin (a slow-release carbohydrate) and sodium may speed your recovery.
After a run, aim for at least 16 ounces of water with food. Or, if you know your sweat rate, replenish with 20 to 24 ounces per pound lost.
1. Over drink! You do not want the blood to become diluted, which will lower sodium and will make you feel nausea, bloating and it can even be dangerous.
It's an excellent idea to use sports drinks that contain sodium.
2. Use aspirin or ibuprofen; they impair the body's ability to excrete water.
BE MOVING, BE WELL!
Raquel ( w.o.m.e.n running coach )