My average watt output on my power computer on my bicycle is about 150W. When I do the conversion from watts to kcal I get a number of about 100kcal/hour. When I look at various websites including this one the average calories burned in one hour with my intensity is 700kcal. Why are my numbers so off? Am I missing something?
Bike Cafe · Public discussion
watts to kcal
Thread details
What we know about this thread
- Original section
- Bike Cafe
- Published
- 13 October 2010
- Last activity
- 14 October 2010
- Original author
- mnaten
- Posts
- 3
- Discussion status
- Public discussion
- Total views
- 9,143
- Views / 30 days
- 0
The navigation and discussion metadata provide context. Posts remain in their original chronological order.
-
-
1 watt = 1 joule/second
4.187 joules = 1 calorie
1000 calories = 1 kcal
1 kcal = 1 CalorieThe human body is roughly 20 to 25 percent efficient. This means that for every calorie used turning your rear wheel, at 25 percent efficiency you are using a total of 4 calories. The extra calories mostly appear as heat.
So.....putting it all together and assuming a ride duration of one hour
kcal burned per hour = 150 joule/sec * 3600 sec/hr * (1/4.187) cal/joule * (1/1000) kcal/cal * 1/0.25 (efficiency) = 516 kcal/hr= 516 Cal/hr
A simple way to do this is to note that 4.187*0.25 is about equal to 1 so you can ignore that part of the conversion. You can then multiply your average watts by 3.6 and then multiply that again by however many hours you have ridden.
-
thank you, that makes sense.
Active in the last 60 minutes
Active in this thread
0 users · 0 guests ·0 bots ·0 total
No signed-in users are active right now.
No known search crawlers active right now.