Hi Isabella,
Absolutely, it happens all the time. This is because muscle weighs more than fat but occupies less space. Imagine you are told to go and fetch one pound of feathers and you are also told to get a pound of metal. You would need a lot of feathers and not so much of metal. They would weigh the same but not occupy the same amout of space. Fat takes up a lot more space than lean muscle.
Look at the picture http://grouponefitness.com/8020body/projects/MuscleVsFat.jpg
to see an example.
If this is happening to you, it's a good thing! You are burning fat and building muscle. Keep at it! All the best.
Move Your Body, Move Your Life
Kenn Kihiu
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