What method is used in calculating the calories burned for a given exercise at a certain weight... duration... etc... I have usually used MET values and it seems that those numbers and your numbers are not even close. For example... walking, 3.5 mph, level, brisk, firm surface, walking for exercise... 157 lbs... 30 minutes... 123.38 calories. If I use my MET values it comes out to 161.10 calories. Just curious what method of calculation you use. Thanks.