I went for an easy 6 mile run today and was shocked to see that my heart rate spiked to 214 at mile 4. It averaged around 175 which is incredibly high for me, especially because this was an easy run. My watch typically reads my heart rate at the lower end of normal so I was pretty surprised by this. I made sure my watch was on securely and that the HR locked before I started. I’m also up to date on all updates. Is this normal for the watch or something I should be concerned about? 214 is extremely high and as a hypochondriac it really worries me.
I've had my 235 watch for a few months now. Great watch with some nice features, but the heart rate monitoring is at times noticeably off.
Today, for example the missus and I took the dog for a drive to a local lake so she could have a swim and a walk. A few minutes away from the destination I thought I'd record the walk on my watch so thought I'd get a gps lock and was surprised to see my heart rate displayed as +90 bpm. A quick check of my pulse and it was much lower...at a guess, mid-50s. I took the watch off, wiped sensor and where it sits on my arm, reattached securely and the reading was still way off. I decided to switch it off and on and it eventually settled.
I've noticed the same thing happens on runs sometimes too.
I do a lot of cycling as well and just in case the Edge fails, I tend to record on my watch too and more often than not, there are heart rate spikes on the 235 which are not recorded on the Edge/chest strap. On one occasion on a high intensity short ride, the 235 had my heart rate at about 120 bpm compared to 160 bpm from the chest strap. It did get more accurate after a while, but it shows that sometimes the heart rate accuracy from the 235 can be quite a bit over or under the correct values.
Personally, I wouldn't worry about it. Ask yourself if you felt ok when you were running. Did you feel light-headed, more out of breath than usual or in any discomfort/pain? If yes to any of those questions, that is when you need to question if there is a problem or not.
In the meantime, perhaps get a compatible chest strap. Pair it with the 235 and see if you get the same results.
Also, bear in mind that I'm not a doctor. My opinions on the 235 are based purely on personal experience. If in doubt, get checked out. I'm not adding this to worry you further as you stated that you're already somewhat worried, but again, ask yourself how you felt on the run.
So many factors affect heart rate. Diet, alcohol, stress, fitness levels. Some of these can result in differences between efforts in a short space of time, and this is before we consider the accuracy of the equipment we used to measure it.
Get a Chest Monitor, the wrist monitor just cannot cut it if you are doing ANYTHING even moderately active. Actually I have yet to find any Optical HR Monitor that is accurate during a relatively easy activity. Not my 235, not my Fenix 3HR, and not my Strava Rhythm Plus. They ALL exhibit the same behavior. Which is about 3 or 4 minutes after getting a "lock" they start estimating the heart rate using an motion based algorithm based on the responses of an "Average" individual, specifically they use someone with a BMI in the mid to high 30's because that seems to be average today. Yeah, I am really disappointed in the Optical Monitors and feel I have been sold a phony Bill of Goods by all those positive reviews online.
Good news is the electronic Chest Monitors are very accurate if you dab a bit of Aloe Vera gel on the contact pads and keep the straps clean They also are relatively inexpensive so if one goes bad due to sweat causing corrosion internally you can just grab a spare and snap it onto a strap. Note, by relatively inexpensive I mean specifically they only cost about 1/3 the price of a pair of good running shoes and last 3 to 4 times as long as those shoes. As for the "discomfort". try waking up with Plantar Fasciitis every single day. Once you get there you won't find the strap the least bit uncomfortable.
I started the habit of restarting my watch before I run each day, which has helped quite a bit. First I sync with my phone so I get my HR data is up to date. I also create my activity a few minutes before I hit start, so the HR can stabilize. A few minutes of extra work, but I find my HR is now 90% on par with what it should be ... still the odd HR spike, but the average is more or less correct.
