# Calories burned with and without power meter

If I ride the trainer with power or my road bike with power Strava or Garmin Connect will tell me I’ve burned around 600 calories per hour.

If I ride my gravel bike that doesn’t have a power meter, both Strava and Garmin Connect tells me that I’ve burned around 275 calories per hour.

How do I reconcile it? Just assume that 600 calories per hour is closer to reality?

I’m also trying to lose weight during my base mile phase and if I give myself 600 extra calories of food for every hour of riding, it feels like too much food.

The data based on power is more reliable, it is calculated from your actual mechanical output. Without power data Strava has to guess your energy expenditure and apparently it assumes you to be way more efficient than you are. Especially with gravel that is not surprising, if their algorithms assumes road riding instead.

For tempo and endurance rides something like 600cal an hour is roughly what I see as well.

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Gravel rides tend to under report because they are assuming a smooth road surface for the rough calcs, but you are obviously riding on a rough loose surface instead

It’s not just gravel. Any ride without power is under reported by about half. I’m actually surprised Garmin/Strava can’t do a little bit better.

Two weeks ago I was traveling for business and rented a bike. Had my Edge 530 and heart rate monitor. Two tempo/sweet spot rides:

• 2 hours 20 minutes (2.33 hours) @ 1517 calories = 650 calories/hour
• 2 hours 10 minutes (2.17 hours) @ 1366 calories = 630 calories/hour

Last week on trainer:

• 630 calories/hour for 60 minutes with 3x10 (30 min) sweet spot
• 660 calories/hour for 60 minutes with 4x8 (32 min) sweet spot and 16 short sprints (~550W for 5 seconds)

The heart rate only ones seem a bit high on cals/hour. Those rides had average HR around 139bpm and the trainer rides were 3-4bpm higher.

Don’t know if matters, I’ve configured my Edge with correct LTHR and FTP.

I’ve had the opposite. Did the same 45km ride over 2hours on the road.
With HR only, it tells me I burned 1750 calories but then I did the exact same ride with HR and Power meter and it says only 980 calories burned.
Rides were 1 week apart.

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Ive had this same situation. On a 2hr 25mile ride with HR only, i would often see 1500-1800 Cals burned.
Recently bought some power pedals, rode the same route and it said that it was a 685Cal ride… its most frustrating because I have been fueling based off of the calorie reports along with my BMR and could not figure out why, with my food tracking, i was not seeing the weight loss I expected.

Why guess? Just use whatever Kj’s you did. A 2h 25m ride at 685 cal would be really really low intensity. 1500 cal seems about right for high Z2 low Z3 ride (500 cal/hr)…

Heart Rate will depend on the inputs (max, resting etc.) at least being ball park. Different computers and apps also calculate it differently. Personally, I’ve found I’ve had expected weight loss using Garmin calculated calories (across several devices at this stage).

My Wahoo Bolt has been off (compared to Garmin) that it made a significant dent in my weekly deficit trusting it. I did initially trust it, and revisited as I wasn’t seeing expected results. That was with the same heart rate data, and even with reducing my wahoo weight by 4 kg! I believe they’ve updated their calculation, but I haven’t had a non-power meter ride to compare since that update.

Where I have power, i use kj. I would wonder whether 685 for 2.5 hours was a single sided not doubling maybe?