Pre-hydrate just before the start of a ride in hot weather. This can be accomplished by drinking 15-20 ounces of cold water or an electrolyte solution. Doing so will help delay the onset of dehydration.
The maximum rate of fluid absorption by the gastro-intestinal tract during exercise is approximately 30 fluid ounces (890 ml) per hour. The rate of fluid loss through sweating during exercise in the heat is close to 60 ounces per hour. This means that with prolonged intense hot-weather exercise, the onset of dehydration is inevitable. Drinking about 8 ounces of fluid every 15 minutes is the most effective way to delay dehydration during hot-weather cycling.
For some cyclists drinking this much fluid may cause discomfort or bloating. In addition, the more dehydrated one becomes, the harder it is for the GI system to absorb fluids. Besides a decline in riding performance, dehydration can cause a variety of unpleasant side effects that include nausea, cramps and diarrhea.
During hot weather follow a smart hydration regimen prior to exercise. A good way to start every day year round is with a large glass of cool water. This helps top off the fluid tank and it wakes up the body by stimulating the kidneys and the digestive process. It also gives a feeling of fullness, which is helpful in reducing excessive food intake. During the warmer months starting the day with two or three glasses of water is an even better idea.
Easiest way is to figure out your sweat rate. You shoudl basically replace the fluids you've lost thru sweating.
1. Weigh yourself naked before riding. 2. Go out for a short but exhausting ride on a hot day. 3. Weigh all the fluids you drank (1 Liter of water is approximately 1 kilo) 4. Weigh yourself again at home, naked, after towelling off your sweat. 5. Your sweat rate should be the amount of fluid you lost plus the fluid you took in divided by the duration of your ride.
So lets say you lost 500 grams of body weight but you also drank 1 liter of water so your sweat rate is 1.5 liters per hour. Then you'll know how much fluid to bring next time when you know how long your riding. Note, this doesn't inlcude rest stops.
its a given fact that man can last for several days without food...and not with out water... and even with food and not drinking water...i dont think we would still survive more likely if a food would clog to our digestive tract... but for me...when i know i'll be riding soon...i try to load as much as liquid as posible...for example on a regular day i consume 9-12 liters a day (that why my officemates ask me to chip in more for our H2O fund hehehehe)if i regularly use a glass which holds 400ML of water i'll use another glass which is bigger for my preparation to an upcoming ride... And on the day of the ride, i take a lil sip for every 5-10minute in order to replenish those fluids that turn into sweat ETC... Like what the prior post said...DON't WAIT FOR YOUR BODY TO ASK FOR IT... An engines radiator isn't filled with WATER not just because it's designed to be...it is ment to be filled because it's necesary for it and is a necessity for us humans.
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