Like (I am sure) many of you, I have spent much of my training time over the past few months on an indoor bike trainer. I love my indoor bike sessions on Zwift. Pure bang for buck training, the bike is set up, I grab a towel, some water and some entertainment and off I go. No faffing with pumping tyres, checking brakes, trying to decide what to wear, finding snacks, sorting a route etc… But as much as I love Zwift and the many benefits it brings over the winter, you can’t beat getting out on your bike on a lovely sunny day and of course the stop for tea and cake!!!
What has become very apparent to me over the weeks when we have experienced sunny weather but been unable to ride out has been the amount I sweat! I am amazed each time I see pools of sweat on the end of my saddle, pouring on to the floor. When I finish and get in the shower, every single piece of clothing is entirely drenched. I always ensure I have plenty of bottles beside me – water with salt, commercial sports drink and homemade sports drink, but there are times when I have definitely come off the bike and suffered with dehydration for the rest of the day. My thoughts raised the questions:
- Am I sweating too much / do I have a high sweat rate?
- Am I pre-hydrated sufficiently?
- Should I only use commercial sports drinks, or is drinking too much sports drink bad for you?
An easy way to see if you sufficiently hydrating to meet your exercise demands is to go to the toilet – urine colour can be an immediate visual sign that you’re hydrated or not.
I got this image from https://www.nhs.uk/NHSEngland/keogh-review/Documents/quick-guides/background-docs/5-Birmingham-urine-analysis-tool.pdf, but if you’re looking for something more specific I have found a couple of articles relating to this issue that are interesting and go some way to answering my questions.
- Asker Jeukendrup, Zwift and my nutrition plan talks about measuring your sweat rate.
- Asker also gives more details about measuring your sweat rate here.
- For a different – yet similar perspective, Andy Blow from Precision Hydration has this article.
I did carry out the little home experiment and it was good to put my thoughts into numbers and normalise the results. To get the best results, you need to repeat the experiment with different activities and in different environments. This data could then be used to help improve / maintain high levels of performance.
Hydration / sweat rate – as with nearly everything in training / coaching – is an individual matter. The requirements of that individual also change over time; particularly for females; but also change with environment, effort, fitness levels and activity. The key to getting the best out of your body, when training and sweating, is to talk to your coach about your physiological and psychological adaptations that are occurring before, during and after your sessions. These conversations will all contribute to developing a bespoke plan – training / hydration / nutrition – for you in different situations.