My new Fenix 5x is giving me wildly lower calorie burn than my previous 4 sevices, which included a Garmin 610, 630, vivo smart and a tracker from another company. While doing the same tennis workouts/drills, and volleyball tournaments, the calories burned are coming out considerably lower than my previous workouts - less than half of the previous calculations. For instance, a two hour tennis drill session used to burn about 1200+ to 1800 cal. The calorie burn according to the Fenix 5x for the same drill session is about 650-750 cal. My other trackers read a significantly higher calorie burn, and according to MyFitnessPal and Livestrong, those activities should be bruning about 1450 calories (and actually, the drills should burn many more calories than actual match play). For volleyball, the readings are similarly low. These are high level, competitive workouts. I played both sports in college and professionally, and am still competitive even at my age (54). I spoke with the Garmin people, and they said that it was because my heartrate was very low and my vo2max was very high, meaning I'm in very good shape. However, I'm in worse shape than I've probably ever been in, and definitely much worse shape (after coming back from a few surgeries) than 1 year ago when the other readings were taken. Anyone have any ideas? Stats: 54yo, 6'1", 190 lbs, RHR 47-50, (yesterday's workout) Ave BPM 96, Max HR 146. This was a a workout with a college player and he gave out before I did. Lots of sweat, changed shirts twice. Just seems odd, all things considered. Help please.
Make sure that before you start your activity, your little heart rate heart symbol is no longer flashing but a solid heart. This means it's fixed onto your heart rate and is getting a good signal.
Be sure your watch is snug so that it's not prone to jiggle while your working out and letting light out that would produce incorrect readings.
Wrist heart rate has limitations. You might wanna wear a chest strap instead. The more dynamic the activity, the less accurate wrist HR seems to be due to wrist flexion and how light is used to read your HR vs chest based systems that read electrical signals instead of blood flow.
I do tend to agree with Garmin in the fact that the higher your vo2 Max and lower your resting HR, the less you burn per workout because your body adapts to the activity and figures out how to burn less in the same workout over time(commonly called "plateauing" in fitness and weight loss circles). So while you shouldn't see a ton of decrease in cal burn, you should see some as time goes on. Halfsies? No, probably not, but 1/8 to 1/4 less isn't out of the question for couch to marathon people. Granted, you said you were fit throughout life, then had surgery, and are coming back but aren't there yet, but still, I'd think you can expect some adaptation to your workout via a lower cal burn.
I'll agree. The OHR on the Fenix's is great for average daily activities but once you start getting 'vigorous' their readings go sideways. Case in point last week I forgot my chest belt so the watch used the OHR. 20 seconds in it had me at 140+BPM and at some point I allegedly hit 172BPM. It takes me 6-8 minutes to break into Z2 on a easy pace long distance run at least. And I never get above 132BPM. My RHR is around 42.
That your average BPM was so low points to either a lack of accuracy on the case of the OHR or a high level of fitness or some breaks in the action. Combine that with a high VO2 and that's why you're getting such low calorie burn rates.
My VO2 max on the new F5 after 5 runs is 18 points lower than my F3. I don't know if it's still 'learning' me, the calculations are different or my F3 was just wonk. So without a lab test, take the VO2 max reading with a grain of salt it may not reflect reality exactly.
I am finding my heart rate and calorie burn is very low with the fenix 5x during high intensity workouts? It seems to work fine for hikes or runs. Is the solution to simply start using a chest strap?
I think a strap is really needed if more accuracy is needed. I find on rides I get reasonable readings - happy enough with it - but it doesn't track as quickly as a strap. I'll stop for a brief moment - my HR will dropped but the watch will sometimes take a minute or so to catchup - at which point I've moved on again.
For instance, a two hour tennis drill session used to burn about 1200+ to 1800 cal. The calorie burn according to the Fenix 5x for the same drill session is about 650-750 cal.
1800 calories for a couple hours of tennis drills is insanely unrealistic.
If anything it looks like it's counting calories closer to reality now than before.
People tend to way overestimate their calories burned during a workout. To get that kind of result you'd need an intensity level equivalent to running 15 miles in 2 hours.
I tend to agree that caloric output seems way low. My most recent weights workout saw me lift a total of 7,491 kg for a 26 caloric burn. Best of all I was supersetting.
I am finding my heart rate and calorie burn is very low with the fenix 5x during high intensity workouts? It seems to work fine for hikes or runs. Is the solution to simply start using a chest strap?
The OHR should do fine for steady high intensity workouts. If you have the watch loose, the more vigorous arm movements of higher intensity workouts can cause problems with the watch "bouncing" and interfering with the OHR readings. The solution to this is ensuring the watch band is snug, and positioned on the fleshy part of the wrist away from the wrist bone. I find I have to have the band one notch tighter for running than day-to-day measurement, but it tracks higher intensity runs just fine. Poor positioning and fit of the watch on the wrist is the most common cause of poor OHR readings.
However, when it comes to INTERVAL workouts, OHR is slow to respond to changes in heart rate, and that is when you are better off with a chest strap.
