Hydration guidelines for endurance athletes have been set at a 1:1 ratio. That is, 1 litre lost through sweating should be replaced with 1 litre of fluids. Runners participating in races or training runs lasting longer than 1 hour, should determine in advance their fluid needs. Using the following procedure during a 1 hour training run will help prepare you for a safe enjoyable workout.
- Make sure you are well hydrated before this test – your urine should be fairly clear.
- Do a warm-up run to a point where you begin to perspire, than stop.
- Strip down and weigh yourself in the nude. Record your weight in pounds.
- Go out for a 1 hour run at your targeted race pace.
- During the run it is important to keep track of the exact amount of fluid you ingest in ounces.
- Do not urinate during the test run.
- When returning from the run, strip down, towel off perspiration and weigh yourself using the same scale in step 3.
- At this point, you may urinate or drink more fluids as needed.
Calculating your requirements
A. Enter your pre workout body weight in pounds. (Step 3) ________
B. Enter your post workout body weight in pounds. (Step 7) ________
C. Subtract B from A. ________
D. Convert your total in C to fluid ounces by multiplying by 15.3 =________
E. Enter the amount of fluid ounces you consumed during the run. +________
F. Add D total to E total. =________
The final figure is the number of fluid ounces you must consume per hour to remain well hydrated. It is important to note that the results of this test will be accurate to the weather and intensity of your workout. For runs longer that 1 hour, electrolyte replenishment is also needed.