Remember: muscle weighs more than fat, but it takes up less space and gives you a more defined and attractive appearance.
Muscles are around 18% more dense than fats. Meaning one person can have less fat and more muscles, weigh the same but look differently from someone with the opposite ratios because fats are less dense and require more volume to weigh the same as muscles.
Muscle weighs more than body fat
But the reason for it is simple: Weight training builds lean muscle mass, which is denser than body fat. A pound of lean muscle mass and a pound of body fat tissue might weigh the same, but they take up different amounts of space.
People who have gained weight in muscle may appear slimmer than before, even though their weight has increased. This is because muscle tissue is denser and takes up less space than fat tissue, meaning that a person with more muscle mass may have a lower body fat percentage and a more toned and defined physique.
Muscle tissue is denser than fat, which means that even if you have a higher weight, you may still look leaner because muscle takes up less space (1). So, if you have a higher muscle mass, it can contribute to a heavier weight without necessarily looking fat.
If you've recently started dipping your toe (or your triceps) into strength training, that could have something to do with the discrepancy between the scale and the mirror. While it's a myth that muscle weighs more than fat—after all, a pound is a pound—it is denser, which means it takes up less space in the body.
The 30/30/30 is a weight loss method that involves eating 30 g of protein within the first 30 minutes of your day and following it with 30 minutes of light exercise. This morning routine is rooted in sound science, and it could be a good way to increase your capacity to burn fat while keeping lean muscle.
You're losing fat but gaining muscle
If you are eating well and going to the gym but aren't seeing a shift in the scale, it may be because you are gaining muscle, which is more dense than fat. This means you could weigh the same, even if your body composition has changed.
If you're asking yourself, “Why am I gaining weight when I barely eat,” several factors may be at play. Your body may be holding onto fat stores if your eating habits are inconsistent or restricted. Or, your weight gain may be the effect of a sedentary lifestyle, medical condition, or long-term stress.
If your clothes are looser but your weight is stagnant (or you're a little heavier), there's a chance you're undergoing body recomposition, a fancy term for building muscle mass and losing body fat, says Hamilton. While building muscle is a long game, focus on resistance training and upping your protein intake.
If you're wondering about weight gain from sleeping post-exercise, rest assured that sleep is a crucial part of recovery and does not directly lead to weight gain. Getting adequate sleep is essential to a healthy lifestyle and can contribute to overall well-being, including weight management.
The rule of thumb, Fernstrom says, is that losing 8 to 10 pounds translates to going down one size. Still, if you lose "up to 15 pounds, you may be OK in your old size," she says. But putting off buying new clothes until you really need them doesn't work for everyone.
Similarly, you may notice increased muscle definition, less softness, and an overall leaner physique. Checking in on how your clothes fit can be another useful rule of thumb. Since muscle is denser than fat, if you've gained weight but your clothes fit a little looser, that's a good sign you may have gained muscle.
Water retention may clear without treatment in a few days. However, if there is a health problem causing you to hold onto fluid, your swelling may worsen over time. You may find that the body parts retaining water become tight, swollen, and painful. If untreated, heart or kidney problems may get much worse.
Water weight is not usually a cause for concern, but it can be uncomfortable and recurring. Reducing salt and carbohydrate intake, keeping hydrated, and frequently exercising are all good ways to lose water weight and prevent it from returning.
Muscle is denser than fat, meaning a kilogram of muscle takes up less space in your body than a kilogram of fat. So, even if you gain muscle and your weight on the scale increases slightly, you can appear slimmer and more toned.
The diet doesn't have enough calories
Eating too little — say, 1,000 calories a day — can prevent you from losing weight, too. "When you don't eat enough, your body is starving and it's not going to lose any extra weight" because it needs those energy stores to keep you alive, Fakhoury said.
Just try to think of your meals in terms of balance. 80% healthy, whole foods, and 20% for fun, less-nutritious treats. The key is consistency over time, not perfection at every meal. So, if one day you have a pizza, no big deal—just aim to get back on track with your next meal.
There are just three steps to it: Eat 30 grams of protein at breakfast. Eat breakfast within 30 minutes of waking up. After breakfast, get 30 minutes of low-intensity, steady-state exercise.