Your sweat rate is the amount of fluids that you lose per hour through sweating during exercise. Sweating is the body's thermoregulatory defence mechanism to ensure that we don’t overheat and expose our bodies to the risks associated with excessively high core temperatures.
As we are all different, we sweat at different rates and your sweat rate can give an indication of how much fluid our body has lost through sweat and give us an indication of how much fluid we need to drink to replace this.
Proper hydration is important in order to prevent dehydration as dehydration decreases your exercise performance.
It must be noted though, that weight loss is not just sweat loss. Glycogen consumption weight loss can be up to 600g and this can occur over anywhere from 90min to 8 hours depending on the intensity of exercise.
Other factors to consider:
Different environmental conditions can have an effect on your sweat rate. In hot, dry or humid conditions you're likely to sweat more than you would on a cold winters morning.
Sweating is a normal physiological process that varies from person to person and is not an indication of overall health.
Calculating your Sweat Rate:
1. Weigh yourself after using the bathroom, just before heading out on your ride, ideally with minimal clothes or cycling kit on.
2. Go for your ride and record exactly how much fluid you drank, this is easy to measure if you drink from a single bottle or two. E.g 500ml bottle = 500 grams and 750ml bottle = 750 grams.
3. After your ride, jump back on the scale and weigh yourself again wearing minimal clothing, preferably the same clothing as worn when weighing in pre-ride.
4. Now subtract your post-ride weight (B) from your pre-ride weight (A) to get the weight you lost during the session.
Fluid lost (C) = A – B
5. Also subtract the weight of the bottle(s) before (X) and after (Y) to find the amount you consumed (Z).
Volume of fluid consumed (Z) = X - Y
6. Now you can calculate your sweet rate.
(C+Z) / time.