Lifting weights is not hard. It's literally one of the easiest and laziest things you can do.
What next? Gonna show him hitting bamboo trees for few days in order to "train" with Enma and claim that's hard work and justifies his asspull power ups?
Training yourself to the point of massive physical pain and still pushing through the pain while being just a normal human, THAT is hard work:
What a load of baloney
in order to tame that sword
he only needed to swing that sword against bamboo trees for few days.
"Hardest training" my ass. 10 year old Oden was wielding Enma with no problem.
Not to mention it was said that Wado is the reason why Zoro was able to handle Enma.
So in reality it's ANOTHER magic sword helped Zoro tame a magic sword.
It just proves once again Zoro gets carried by his swords. Even his swords have to do the training FOR him.