Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

TorontoSS

macrumors 65816
Original poster
Nov 9, 2009
1,093
397
When I run, my avg heart rate is around 160 and in about 30 min I burn about 200 -210 active calories. Today I swam and the avg heart rate was 118 and in 30 min I burned 285 active calories.

So my question is, does the Apple Watch over report/inflate swimming calories?
 
Swimming requires less work from the heart since it doesn't have to pump blood up to your head so it pumps at slower rate.
 
When I run, my avg heart rate is around 160 and in about 30 min I burn about 200 -210 active calories. Today I swam and the avg heart rate was 118 and in 30 min I burned 285 active calories.

So my question is, does the Apple Watch over report/inflate swimming calories?
That sounds like the ballpark. Garmin shuts off HR, so it cannot use HR for calorie estimates. That said, my Garmin gives me about 600 total calories/hour for a pretty intense swim workout. Just based on RPE relative to biking and running workouts, I estimate that my HR is probably in the ~120 range for longer intervals (>500 yards) and ~130 range for 50 yd to 100 yd intervals. So, if you swam around 1,500 yards in 30 minutes, and you were not gasping for air, then 300 total calories and <120 HR sound about right.

Also, I recommend looking at Apple's total calories for a workout, because it under-reports active calories for many people (inaccurately shifts calories from the active to the BMR category in presentation).
 
Last edited:
Thanks for your insights. I didn't know that - I always assumed if your heart rate is higher, you're working more and therefore more calories burned (and assumed running burned more).

Thanks!
 
I always assumed if your heart rate is higher, you're working more and therefore more calories burned (and assumed running burned more).
If you have a strong engine, you can burn more calories per minute biking or running. It is pretty hard to burn more than 10 calories/minute swimming simply because it is difficult to get the oxygen intake. However i think an average swimmer can burn more calories/minute than an average runner.
 
  • Like
Reactions: TorontoSS
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.