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Body Battery

by Mark Jardine 8 Feb 2021 15:00 PST
INEOS TEAM UK racing in Auckland © Harry KH / INEOS TEAM UK

I've been a bit of a luddite when it comes to fitness tracking and smart watches, for many years just 'going with the flow' on my morning runs, going out sailing and, more often than not, recharging my batteries with a beer. No harm in that I hear you cry, and I tend to agree, but over the past year I've been using Strava and now have a Garmin Fenix watch to track my runs.

Sail-World.com's North American Editor David Schmidt has been urging me to get a fitness watch for some time. We both lead an active lifestyle and he's been raving about his since he bought one last year. He put it to me perfectly when he said, "Nobody goes big-boat sailing without real-time boat-performance data, so why would you train for sailing without real-time fitness and body-battery metrics?"

It's most likely a product of lockdown that led me to finally try the technology, as opportunities to go sailing or windsurfing aren't on the table and I was needing something to keep motivated when out running. I've only had it a few days and have to admit it is fascinating looking at the data that is coming out of a small device strapped to your wrist, which I used to only use for telling the time and counting down to the start of a race. The most enlightening information is that on 'Body Battery'.

Garmin describe the Body Battery as using a combination of Heart Rate Variability, Stress, and Activity to estimate a user's energy reserves throughout the day, displaying a number between 1 and 100 that represents the individual's energy level - the higher the number, the more energy the user should have. So far it does seem to tie in with when I'm either bouncing or feeling run down.

So, what's this got to do with sailing? Why, when I've concentrated so much time writing about fun in sailing, am I now harping on about fitness monitoring? Please bear with me...

This Saturday is a big day in Auckland as the America's Cup challengers INEOS Team UK and Luna Rossa Prada Pirelli lock horns in the PRADA Cup final. There is much talk about the 'engine room' of an AC75, which is the grinding pack who provide the power for the mass of hydraulics throughout each boat. Fitness tracking for these sailors is taken extremely seriously, making sure that everyone is in peak condition on race day. With the intensity that is required for the 30 minutes or so of each race, it's essential that they can perform at 100% when called upon.

Every team has dedicated performance coaches and the fitness tracking goes way further than measuring pulse rate, but the principles a smart watch is using are along the same lines and, used correctly, can monitor your body battery.

Here's where it links in with the fun. We all know that when we're energised, we enjoy an activity more, so if your body battery is charged ahead of a sail then the likelihood is that you'll have a better day on the water. You'll execute those roll tacks better, make decisions faster and generally feel more connected with the water - it's when you feel 'in the groove'.

So, can we use the technology to control our sleep and exercise prior to a sail to be fully charged going into the day? Unfortunately, the practicalities of life often get in the way: a hard day at work, a bad night's sleep or just feeling a bit under the weather. But maybe just the awareness that your body battery isn't at 100% can help you understand when a race isn't going to plan, so instead of getting down on yourself about it, you can look at things in context.

Is this some kind of epiphany for me? I'd say yes and no, as I generally know how I feel at any given point, but having the data presented in a clear format is useful, particularly when it comes to sleep. This is the first time I've seen how much deep, light and REM sleep I have each night. I need to read up on what it all means, and how much I should actually be getting, but I'm fascinated by the details.

The old adage of 'knowledge is power' applies very well, and if you're heading out for a sail, knowing your body battery is down, then trying to fit in a rest beforehand could turn a bad day on the water into a good one. We're going out on the water to enjoy ourselves, so any tools we can use to help us achieve that goal must be worth it!

For the British and Italian teams in Auckland, come Saturday they'll be looking to have their grinders at 100%. The power they generate enables the tacticians to make the decisions they want to on the racecourse. As we saw in the Round Robins, the racing between the two teams can be incredibly close, so points can and will be won and lost by tactics, and the ability to pull off manoeuvres quickly.

For us mere mortals, the weekend warriors and beer can racers, I'm hoping this technology will helps us enjoy our sailing more. Then, after a good day's sailing, we can charge our glasses and enjoy chatting over it all again in the bar. It may be a different kind of recharging, but in my opinion it's just as important and an integral part of sailing.

Mark Jardine
Sail-World.com & YachtsandYachting.com Managing Editor

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