Even before Matthew asked the system about his jumping prowess, he had already figured out to some extent that with the added weight on his torso, he would lose some distance from his jumping distance. He doubts that with his new body, he would be able to jump 10 meters away as easily as before if he didn't use his aura to boost and enhance his leg strength.
And besides, his current body didn't look proportional in size with a large and broad torso and slim and thin-looking legs holding up his hulking chest and arms.
Although there's no way that Matthew could have thought of a way to make his body lighter again without losing the great boost to his strength, Matthew still got an idea that might be feasible for him to alleviate the penalty of having a huge body.
'It might not be possible to lighten my body weight to retain my jumping capabilities, but can I just strengthen my leg muscles instead to make up for it?'