Manually Logging Activities and Accuracy

[Alcyon]

Here is my questions.

When manually logging activities, how accurate is the calorie burn?  Activities that appear in the Fitbit drop down menu appear* to underestimate calorie burn...  For example, if I use the elliptical at the gym for 30 mintues, it estimates a calorie burn of 385 cal, but the Fitbit dropdown selection suggests a burn of 248 cal...  Similarly, when I log a 40 minute spinning class, the calorie estimate is 247 cal, but I have read that high intensity spinning can burn upwards of 600 cal/hour.  So which estimate is more accurate?  I have a Fitibit Charge which is useless at accurately tracking calorie burn for these activities.  It is important for me to get an accurate reading since I have reached a plateau with my weightloss and need to determine if I am over-training or over-estimating my weekly calorie burn/consuming too many calories...   

Thanks for your input.  

[WendyB]

If you are getting the calorie burn off the machines they are notorious  for being wrong.

I think the smaller number looks correct. I use a Polar HRM and there is no way I come close to 600 calories for a spinning class

[USAF-Larry]

I have learned that unless the machines at the gym such as the elliptical, stationary bike, treadmill, etc., allow you to input you weight, height etc., the estimated calorie burn is way off.