Wahoo records my rides, Strava is social media, both give me calories burned so adjust my diet.
Not very well versed w/ caloric expediture, but usage of a power meter is indeed more accurate for caloric expenditure vs HR only.
Even so, i believe it’s not 100% and Calorie calc are based on the Average/NP of the session, so in the above 2 screenshots, I see 145w NP and 138w
What difference are you referring to? KJ / Total Work is really the only field that is in both screenshots and it’s basically the same in both (330 vs 328).
KJ is average power times duration in seconds, then divided by 1000. To convert from KJ to calories you have to do some more conversions and make an assumption about gross mechanical efficiency. It looks like Wahoo uses KJ = calories, which is the most conservative assumption meaning your efficiency for the ride is right around the highest that’s been documented in research. Strava uses something like calories equals KJ plus 10%, which is going to be more realistic for most people in most situations.
I’d use Wahoo (KJ = calories) if KJ are relatively small (<1000) and I’m trying to lose weight. I’d use STrava if I want to maintain weight and make sure I fuel and recover from my training properly.
Just checked my last few rides on Strava, and for me it uses kcal burned = kJ of work done. This is based on the approximation that conversion of fuel into work is roughly 25% efficient and roughly 1kcal = 4 kJ. It’s rough and ready but probably vaguely accurate for most people.
In the past, when I didn’t have power data, I think Strava was overestimating kcal burned, sometimes up to double.
if strava uses their “virtual power” to calc calories then yes, it would be overly inflated
A professional athlete will be closer to 25%, at a certain intensity, while is mere mortals would be closer to 20%. The values printed on food labels are also not exact numbers and there can be acceptable variances in the amount of calories.