And sure, when you picture a 'good work out', what usually comes to mind is being red in the face, dripping profusely and feeling hyped enough to bounce off the walls.
But is how much you perspire a true indication of how much fat you might be tearing through, as you train?
'Sweat is an indicator of your body’s temperature regulation, rather than how hard it is working – and these can be connected, but are different,' says sport scientist for Auster Fitness, Harry Aitken. Think: hitting your deadlift PB probably destroyed you, but you likely didn't sweat as much as when you were coasting in your last spin session.
As to any apparent weight loss effects that seem to be down to how much you've been sweating? They're not really legit. Karen Austin, Founder of Topaz Fitness Academy, explains that 'sweating is literally a loss of water instead of a loss of fat, therefore [any apparent weight loss] will be temporary – until your next glass of water'.
Sweating and weight loss: cardio versus strength training
Okay. So you are likely to sweat less at the weight rack then you are on the treadmill. But what does that mean for torching calories? 'You will likely sweat a lot less doing weights as you take rest periods between exercises, allowing your body to cool down,' says Aitken.
However, that doesn't necessarily mean that you'll ultimately lose more weight doing cardio than strength training. This is a complex topic, so we'll direct you this way to read up on strength training versus cardio for weight loss.
Sweating and weight loss: Remember, everybody is different
It's also wise to remember that our bodies are all built a little differently. 'Some have more sweat glands than others,' says Austin. People with more sweat glands are going to perspire more, natch – but that does not mean that they're on track to lose more fat than a person with fewer glands who is working to the same intensity.
The upshot is that 'going by just sweating alone is not a good indicator of how much weight you're going to lose or burn.'
Does sweating help you lose weight: the verdict
Long story short, no. Sweat volume also does not indicate how fit you are, nor how many calories you're going to burn. A good sweat sesh can work wonders for getting glowing skin, by carrying grime out of your pores (just make sure you wash your face after working out, STAT, to stop any gunk resettling into your complexion) and can certainly help you feel like you've gone hard.
But, when it comes to weight loss, it'll always be how much you put in, rather than what you sweat out.