Derm told me to stop lifting while on accutane

Went to my derm today as I was experiencing bad side effects such as joint pain and dry eyes from my 20mg daily. Unrealted to these side effects she said that she recommends no exericise other than walking while on accuante. She said her simple explaination was that exercise releases creatine kinase which causes strain on the kidneys.

I can't stop lifting so its either I stop accutane or conclude that my derm doesnt know what shes talking about. From what I've read and from what I've seen on here lifting on accutane is perfectly fine.

Has anyone asked their derm about lifting on accutane, what did they say if you dont mind sharing?