It is a satisfying feeling to sweat during and after a workout; it makes you feel like you did a nice calorie burning, thorough work out.
However it is a misconception that the more you sweat the better your work out. In fact experts say that is not a good idea to induce heavy sweating, which could have detrimental effects on health.
Sweating and the amount you sweat depend upon a variety of factors, external as well as internal. Sweat does indicate that you had a good work out, but more sweat does not necessarily mean a better work out of more calories expended. There are other factors at play:
The climate: Obviously the hotter it is the more you will sweat. So you will sweat more in summer than in winter. Does that mean you burn more calories in summer than winter? Not quite!
Your fitness levels and all other things being equal, you will burn the same amount of calories in winter as in summer doing the same exercises even if you do sweat more in summer.
So in that sense, sweat does not ‘melt’ the fat away from your body. It is however possible that you may lose a few more calories if your body temperature is more elevated.
The Kind of exercise: If you are on a stationary bike indoors, you will probably sweat more than if you were outside on an actual bicycle with the wind in your face and the air cooling your body.
However merely the emergence of more sweat on the stationary bike is not an indication that you are getting a better work out. Yes you may get a better work out if you increase the resistance of the stationary bike or its difficulty level, but sweat is not the indicator.
Similarly jogging on a tread mill may make you sweatier than jogging outside in the cool air, but that does not mean you get a better work out simply by being on a treadmill. [treadmill exercise]
You may lose more water not more fat: If you are sweating more during a work out and find that this helped you lose some weight as against a similar work out which did not have to sweating as much, then you have to understand that that weight loss was from water lost during the workout. It was not more fat burnt, but more water lost, which is not necessarily a good thing.