So first of all, when I swim, bike, run, I do so with heart rate being a measure that I train to. I subscribe to the Maffetone method (basically 180 – your age being your maximum aerobic training heart rate – good summary by 6 time Ironman Kona champ, Mark Allen).
I’ve been having some problems with it spking when I first start my workouts for a month or so. I was wondering if it was me and my heart rate was escalating rapidly when I didn’t take the time to do a good warm up, or if the batteries in my HRM strap were going or if there was something else wrong. After googling a bit a while back, I started to think the problem might be caused by static electricity from tech shirts. I’d read that could be the problem and in line with those articles, my heart rate typically dropped back down as I got sweaty and the wetness trumped the static.
Today, I verified that this was certainly the case in my situation.
I had a tech shirt on and as it had gotten remarkably cold today, I was also wearing a tech jacket. When we started the run, my heart rate zoomed up to 230+ and I wasn’t running hard at all. I’ve gotten used to the spiking at the beginning of workouts but I’d never been near this. I walked and ran a few times without much effect & then I took of my jacket. When I did that, my heart rate immediately dropped to 180/190. That was a pretty good indicator for me. Continuing to run, I pulled my tech shirt up and held it above my pecs. My heart rate dropped straight down to 130/140. I even pulled my shirt off for a bit and it remained low.
I didn’t want to run without a shirt the entire way so I put it back on and my heart rate jumped back up to 180+.
All the while, I’d been running at the same slow pace that I typically can do and keep my heart rate below 140.
It also makes sense that this is getting worse as we move into winter and the air gets dryer. I think for me that it’s back to cotton shirts. I also read that spraying your shirt around the heart rate strap area with Static Guard can prevent the issue. Going to give that a try.