Calorie Burn Feedback

Hi,

Would love some feedback/help on calorie burn if anyone has a moment to spare.

I've been trying to get an idea of how many calories I burn on my exercise bike, I use a fitbit to record my activities, I've tried wearing the fitbit on my ankle and on my thigh, the fitbit measures the steps accurately both ways as one revolution a step, but the ankle is twice the calories burned as the thigh.

If I put the activity in MFP it comes up with calorie burn about the same as wearing the fitbit on my ankle.

However it seems very high.

I have also tried to google this topic but I have found conflicting information.

Using this site http://www.healthstatus.com/calculate/cbc I get a result similar to wearing the fitbit on my ankle, and to MFP.

Now for some figures.

I currently weigh 313 lbs. I do 30 minutes on the exercise bike without dipping below 20km/hour. I push the resistance as high as I can handle. It is hard work, for the same of the calculator on healthstatus I called it moderate.

The results I get are usually between 500-600 calories burned. I can't help but feel this is too high.

When I first started using the exercise bike I did struggle to do 10minutes. If I push it I can do 40 now.

I realise for an accurate figure I would need a HRM, but I just want to know if the figure is in the ballpark or should I wear it on my thigh, effectively halving the calorie burn.

Any feedback would be greatly appreciated.

Thanks,

Brett