I am a sporty person, 1.80 meters tall and weighing 78 kilograms. All my swimsuits are medium to large. I bought this one in large for safety, and it is tighter than all the mediums I had in the past. I cannot judge it as I cannot even take a step if I wear it. The size of this swimsuit seems to be extra large, which is unreasonable for a person weighing 78 kilograms. It's a pity that swimsuits cannot be returned - update: I ended up giving it to a friend of mine who is 1.69 meters tall and weighs 65 kilograms, and it fits him perfectly. He has never worn a large in his life, he always wore small