I wondered if I should have put more thought bubbles here to explain Walter's thought process, but I think it works better if it's ambiguous whether he wants the professor to go away and hopes he'll get bored and leave, or if he's considering taking up the offer, and if so, if it's to legitimately listen to the advice and improve his squat form, or just to have direct physical contact with him.
I guess we'll see in the next page.