There's an old saying floating around that you may have heard if you've ever started working out and are trying to shed some weight.
How many times have you said to a friend, "I'm dieting and exercising but I'm not losing any weight!" and then said friend comes back to you and says, "But you're building muscle and muscle weighs more than fat"?
I'm currently in the middle of a 12-week transformation program where I cut out processed foods, alcohol and carbohydrates for the first two weeks.
But despite all that self-discipline (and boring nights out on the soda waters), weight-loss has been super difficult for me to achieve.
In fact, after I lost 1.8kg in my first week, I've either stayed the same weight, gone up a kilo or then fluctuated throughout the week.
And while my measurements have slowly started to drop, I just can't seem to get the numbers on the scale to move.
Over the last week, the intensity of my training has certainly increased. I'm fitter, stronger and my eating habits are healthier than they've ever been.
My body is toning up and my face has slimmed down, prompting ooh's and aah's from those around me.
But a recent conversation with a friend about weight loss made me question everything. Is there weight to the myth that muscle weighs more than fat?
Spoiler alert! It doesn't. And here's why.
"Your total mass is made up of your Fat Mass (FM measured in kg = body fat) and your Fat Free Mass (FFM measured in kg = everything else)," Nicholas Chapman, PT and director of Rushcutters Bay Health and Fitness explained.
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Nick used an average woman who weighs 70kg as an example. Her body fat was 30 per cent of that weight, therefore her FM is 21kg and her FFM is 49kg.
"Your FFM is mainly made up of your muscle mass," he added.
"For context, muscle mass is quite hard to put on. You require a high volume of intense strength training combined with a caloric surplus (eat more then you burn everyday) at the correct macro split."
In fact, your FFM is likely to be the same unless it's put "under serious duress to change".
So how come my weight is fluctuating if I'm eating all the right foods? The answer is in the water.
"Fluid levels shifting in the body cause the biggest swings on the scales," Nick told me.
"When you hear of massive weekly weigh in results, its fluid, not fat. This is due to changes in diet (i.e. being high carb and then going Keto for example) or for non exercises starting weight training (can make makes absorb more water for a little while).
"This all levels out after a few weeks if a consistent diet and excise approach is followed."
So basically, for some people (i.e. me), your weight might be a little all over the shop at first.
But if you stick to a consistent, sensible diet with a reasonable caloric deficit, and you incorporate strength and cardio training into your routine, over tim, the numbers on the scale will start to decrease.
Can I get a "Amen" up in here?