I had never labelled myself as a sweaty person until I started riding a bike a few years ago – working with FLOWBIO as a Beta Athlete has been an amazing experience, but has only served to confirm just what a heavy sweater I am.
What is the FLOWPATCH?
The FLOWPATCH from FLOWBIO is a biosensor platform that collects and analyses fluid and electrolyte losses through sweat in real time. This will allow athletes like me to enhance their training, and recovery as well as plan a personalised hydration plan for their races.
I’ve been working with FLOWBIO since 2020 – the very first trials involved collecting sweat in pipettes and posting it back to the Lab for analysis. Since then I’ve been to their offices to test the first iterations of the biosensor and was lucky enough to be one of the first to get the beta FLOWPATCH and app to test.
As a business FLOWBIO has recently gone through an investment round, to get the funding to be able to launch the product to the market, which is really exciting.
So what?
I’ve been using the version 2 biosensor, pictured above, now for a few months and have been amassing a lot of data. But data is nothing if you don’t use it. So I’ve been downloading and crunching numbers to create a tailored approach to hydrating my training. I just wanted to share a little bit of that in this blog, by looking at the last 10 indoor, high-intensity workouts I’ve completed.
The feed from the FLOWPATCH gives a range of data markers, which I’ve shown in a couple of images below using last nights 5 x 15sec all out sprinterval session, courtesy of Coach Pav Bryan. The image on the right shows the session summary, which is guiding you on what you’ve lost and what you need to replace in order to optimise your recovery. The left image gives you a session based summary of all the data markers, which I’ve been analysing to see what makes a difference and what variables I can control and change to affect my performance and recovery.
Reviewing these data markers, I can summarise a few things immediately;
- Sweat Rate – for higher intensity sessions, such as V02 Max and Sprint Intervals that I’ve completed indoors, I will sweat out an average of 1 litre of fluid per hour,
- Sodium Loss – as you’d imagine, the more I sweat, the more sodium I lose. However, this doesn’t always correlate because if the sodium concentration of my sweat is lower then, naturally I will have less sodium to lose. My loses range from 1200mg/h down to 500mg/h but averages out to around 800mg per hour.
Why this matters?
I spoke to the guys at FLOWBIO to give me the low down on sweat. Sophie Killer told me that “dehydration by as little as 2% can have a significant impact on your performance – reducing your aerobic performance and hand-eye coordination, which are pretty important in cycling.”
So, taking that point further – I’m about 64% water (using the Watson calculation), so losing a litre of fluids over the course of an hour’s workout would be that 2%. So, not replacing it at all would dramatically affect my performance and my ability to continue riding. Go beyond an hour’s ride and you can see how poor management of your fluid and sodium losses could actually become a real problem.
Everyone sweats differently and everyone loses a different amount of sodium in their sweat too – from as little as 200mg per litre up to as much as 2000mg. In science terms, a 2015 study found that athletes who were on top of their sodium loses, replacing what was lost through sweat, finished a middle-distance triathlon an average of 26mins faster than those who didn’t.
So, what have I changed?
The FLOWPATCH biosensor and the data collected has meant I’ve been able to make some immediate and easy changes to how I train
- I’ve now switched to Precision Hydration tablets – knowing how much I sweat and the amount of sodium I lose as a result means I do need to be using a tablet with a much higher sodium content than I had been. So, for most sessions I’m using the PH1000 tablets during but also for the very long rides, I’ll pre-load with a PH1500 tablet the night before,
- I’m much more conscious of my need to rehydrate properly for recovery – I was a bit footloose with rehydration, but the data gives me a guideline of what to drink post-session, so I’m giving my body the best chance of recovering ahead of the next session,
- I’m drinking a lot more on and off the bike – If you watch GCN videos or most coaches talking about hydration, the rule of thumb of 500ml bottle per hour on the bike is always a good one. But seeing just how much I’m losing in volume has prompted me to be more mindful of what I’m drinking during the day but also when I’m on the bike
All interesting, but the point of collecting all this data is to understand just how I sweat – volume and concentration – so that I can build a truly personalised hydration strategy that will support my ambitions of completing the world’s toughest bike race – the 3,000mi Race Across America – in 2024.
More immediately, however, it’s about collecting more outdoor data so we can work on building a hydration plan we can test at my next race in June – the inaugural 1,000km self-supported Solstice Sprint.
So, time get go A La La La La Long….and sweat, because #Sweatisdata
Finally just a word of heartfelt thanks to Stefan, Sophie and Will particularly from FLOWBIO who’ve been incredibly helpful and supportive and put up with my endless questions and limited tech-savvyness. I genuinely believe this is going to be a game changer for so many athletes, but on a personal level it will be one of the key factors in me completing Race Across America in 2024.
Find out more about FLOWBIO at https://www.flowbio.com/
Guy Stapleford Ultra 