I suppose this means that at some point Chris Hemsworth will be back to his typical look in Thor: Love and Thunder.
It seems Thor might have needed the same training that Chris Hemsworth uses.
At the end of Avengers: Endgame, the last time we saw the character, he was still in his “Lebowski” shape.
We don’t really know exactly how soon after those events Love and Thunder will pick up; Hemsworth could still start the movie looking like that but then eventually get back in shape.