How to Tell If You’re Gaining Muscle without Weighing Yourself

You don't need to buy a special weighing scale to know if your weight gain is due to an increase in muscle mass or fat. Here's why.

Young content woman in black sport clothes standing on scales

You've been doing everything right: eating enough calories, hitting your daily protein intake, and training hard at the gym ?

The good news? The number on the scale is steadily climbing – from week to week.

Only … there’s this niggling thought at the back of your mind: What if you’ve got everything wrong? What if you’re gaining fat instead of muscle?

I mean, of course, muscle gain usually leads to weight gain. But then again, the same applies to fat gain?! So, unless you have a scale that can determine your body fat percentage, you wouldn’t be able to know for sure.

Don't sweat.

There are several ways you could ascertain if you're indeed packing on muscle mass – rather than all that chubby goodness – without forking out extra money for a new weighing scale. The dough could be put to better use, anyway (e.g. grocery bills for protein!)

By the way: these methods are also suitable if you're trying to avoid weighing yourself altogether, for your mental health’s sake.

Measure the circumference of your muscles

This is a pretty self-explanatory way to track muscle gain – without stepping on the scale.

A disclaimer: you'll experience the same shortcoming (i.e. you can't be 100% sure that you're gaining muscle instead of fat) when using this method.

Your circumferences are bound to increase if you’re packing on the pounds.

Thankfully, the following tips can help you be a little surer that your increases in muscle circumferences are indeed due to muscle instead of fat.

When you measure yourself:

  • Focus on your biceps: In general, men tend to store fat around their abdominal area – while women store fat around their hips and legs. So, an easy workaround that applies to both sexes to see if you’re indeed putting on muscle is to measure biceps circumference. This applies even if you aren’t doing any direct bicep work. That’s because other movement patterns (e.g. rowing, pulldowns) invariably involve the biceps.
  • Make sure to flex as hard as possible: This helps with consistency. Imagine if you took measurements of your flexed biceps one day, then measured the next day again with unflexed arms. That’s super misleading. So, remember to activate the mind-muscle connection even as you’re taking your measurements. You want it as accurate as you can get.
  • Average 3 measurements each time: Ensure you take your measures at the same spot every time. To make things easier, you might want to reference the peak of your biceps. And as for why you need to average out 3 measurements? Well, that's to reduce the 'error' of your measurements. It's a statistics concept that you needn’t worry yourself with too much.

Take progress pictures

Here’s something to ask your loved one: “Hey, am I gaining muscle or fat?”

Chances are, they’d be able to tell. One thing’s for sure. Muscle gain looks different from fat gain. And that's why one of the ways to know if your weight gain stems from an increase in muscle mass is to take progress pictures.

But of course, because of celebrities and fitness influencers, we’re all well aware of just how deceiving pictures can be.

This is why you're going to do the following when taking your pictures:

  • Wear the right clothes: This helps you get a clear idea of how your body’s changing over the weeks. But what is considered ‘right’? For women, that means a sports bra and biker shorts. As for men, it’ll be boxers. It all depends on your comfort level – but, in general, the less covered-up you are, the better.
  • Capture your front, side, and back view: This goes hand-in-hand with the point above; you want to get a clear idea of how your body’s transforming – from all angles. And that includes your side and back view (otherwise, how would you know if all that rear delt work has been paying off?!)
  • Take at the same time every day: While the best time to take progress pictures will always be the time you can stay consistent with, ideally, you should still take them right after waking up. That's because many different factors – including your meals, hydration levels, and NEAT – can affect how your body looks. And these factors vary daily.
  • Use the same lighting conditions: Ever seen your abs popping under specific lighting at the gym – then pull a disappearing act on you the moment you reach home? Lighting is everything. Just ask fitness influencers. So, no matter which lighting you choose, make sure you replicate it. In every single picture.

Log the weights you’re using for every exercise

Now, moving on to a non-aesthetic way to determine if you can indeed thank muscle gain for your recent weight gain: take a look at the weights you've been using.

Have you been progressively overloading? Or, in other words, using heavier weights?

If so … congratulations! You can be nearly 100% sure that you’re gaining muscle. Of course, as usual, here’s a caveat. This only applies to you if you’ve been consistently performing the movement pattern for at least 1 to 2 months.

That’s because any improvements you make when you first learn a movement pattern (e.g. barbell squat) are primarily due to neurological adaptations.

Your brain just got better at recruiting the muscles needed, and your muscles learned how to better coordinate with each other to generate the forces required. But these adaptations only last for a few weeks.

After that, your 'strength gains' are all due to muscle gains!

Thus, highlighting the importance of:

While the staying consistent bit largely falls on your shoulders … we can offer you help if you’d like to track your progress on weights used in the gym – across exercises.

How? With an AI-powered personal trainer app called GymStreak. Its sexy interface makes logging your workouts so easy; you'll wish you discovered it right when you ventured on your fitness journey. Thankfully, it's never too late to get started now:

Get GymStreak


Ahtiainen, J. P., Walker, S., Peltonen, H., Holviala, J., Sillanpää, E., Karavirta, L., Sallinen, J., Mikkola, J., Valkeinen, H., Mero, A., Hulmi, J. J., & Häkkinen, K. (2016). Heterogeneity in resistance training-induced muscle strength and mass responses in men and women of different ages. Age (Dordrecht, Netherlands), 38(1), 10.

Data Reduction and Error Analysis. (n.d.). Retrieved July 16, 2021, from reduction and error analysis/data reduction and error analysis.html