The numbers are based on the assumption that each of these was done for 30 minutes, except where different time is mentioned. Hopefully it will help us. The order is from most calories to least calories.
you should have a carb rich meal half an hour before ur workout and protein meal right after ure done working out, because thats the most crucial time when ure body needs protein.
These numbers are, skewed is not the right term. but they are presented in a very general way to the audience. The different levels and variations of each machine and the potential of individual resistance will determine how many calories is each person burning.
On the other hand, playing cards for half hour is stamped in as 59 and kissing at 36. Can't complain now, can we? :p
Yeah of course these numbers are not 100% accurate. The number of calories burned would depend on how much you put into the exercise. These are just estimates to tell us what we need to do more of.
Calorie burning is not an exact science and should never be taken as such. It's at best an educated guess.
For example, it says jogging for thirty minutes burn 338 kcal but it really depends on speed, your weight, where you are jogging and even your own body. People who run all the time, will probably burn less than someone who is running the very first day.