hi

Question
I want to know if there's a way to calculate the calories I burn in a treadmill?

Answer
Jairo, there is a way. The best way is to go into an exercise physiology lab and have a mask put on you and have it tested via indirect calorimetry. That however is not practical. It is however how they determine if a formula is useful or not. The following is a formula that will allow you to calculate how many calories you are burning. A big benefit of this one is that it takes into account heart rate and your weight. Make sure you notice that the exercising time is in hours (not minutes).

Male: ((-55.0969 + (0.6309 x heart rate in beats/minute) + (0.1988 x Weight in kilograms) + (0.2017 x Age))/4.184) x 60 x time exercising in hours

Keytal, et al. Prediction of energy expenditure from heart rate monitoring during submaximal exercise. J Sports Sci. 2005 Mar;23(3):289-97.

Please let me know if I can be of any more assistance.