Short answer: They weigh the same (a pound is a pound!). But they sure don't look the same. In other words, a pound of fat has a much larger volume. But a pound of muscle appears leaner and more toned.
If you're building muscle while losing fat, the scale might not go down. Despite weighing the same, you could potentially have an improved physique. That's why in addition to jumping on the scale, I would also encourage you to take progress photos.
Your body composition can change even if your weight remains the same. This can be due to factors such as a shift in the ratio of muscle mass to fat mass, changes in body water levels, or fluctuations in the amount of glycogen stored in the muscles.
The basic answer is yes, you don't have to put on a noticeable amount of fat to also gain muscle. You just need to work out, eat enough protein/nutrients and enough calories to supplement muscle growth.
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.
“Muscle tissue is denser than fat tissue, so it takes up less space,” says Barron. “This is exactly why your weight may not change, but your clothes are feeling looser.” This is one of those situations where you should keep doing exactly what you're doing.
The Scale is Going Up
You might not see your biceps pop right away. The first sign that you're building muscle may be an increase in body weight. The number on the scale goes up because muscle tissue is denser and heavier than fat. Therefore, it takes up less space for the same amount of weight.
Strength training helps you lose weight and keep it off by building muscle tissue. The more muscle mass you have, the higher your metabolic rate tends to be. More muscle also helps your body burn more fat than muscle, which is important if you want to lose weight and keep your strength.
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. This means that muscle and fat may look the same on the scale, but they'll look different on your body. While your clothes may feel looser, the scale may tell you otherwise. Count this as a win.
On average, one can expect to lose between 0.5 to 4 inches in a month. (up to 1.8 kg) It can be more or less also. It varies from one person to another.
The volumic mass of muscles is around 1.1 kg per liter, while it is 0.9kg per liter for fat. You probably confuse being muscular with being lean. Someone with little muscles, but with very low body fat will look muscular.
The key to losing belly fat is incorporating the right activity type, and strength training is one of the best ways to do it. When you lift weights, especially focusing on compound movements like Squats, Deadlifts, and Presses, you're engaging multiple muscle groups and boosting your metabolism.
So even though you may be losing fat, you're gaining muscle. You might feel slimmer, even as the number on the scale rises. “The scale doesn't tell the entire story,” said exercise physiologist Christopher Mohr, PhD, RD. “Since muscle and fat take up different volume, they look very different on the body.”
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.
The most accurate way to tell if you've gained muscle is to get your body fat percentage tested. You can do this by getting a DEXA scan or taking a hydrostatic body fat test (where you're submerged in water while sitting on a scale).
You're gaining muscle. The scale might be stuck because you're building up your biceps and glutes—and that's a good thing. The number on the scale is less important than the breakdown of how much water, muscle, and fat are in your body, Jovanovic says.