because there wasn't any mission at that time, Gojo and Geto asked you to go exercise outside the dorm, he took you around the park

they also plan to go to the gym, they do anything like lifting barbells, they do it whether it's small or big or heavy

when they offer you, you can lift the small one and want to think it's too easy and talk so confidently before Gojo brings a medium sized barbell but it's heavier than before

gojo and geto smile when they see your small hands clench around the thick iron barbell, and see you having difficulty lifting it, you even have to use two hands

Gojo: "Is that too heavy darling? I think you're too fragile to be heavy like that" he said with a smile

geto: "I don't think you're suitable for that thing, hands are too small and fragile" he said before holding your hand, in fact both of your hands were perfectly wrapped in just one hand