No they dont. Realistically they would need years to get to the lvl these 40-60 year old men are at. No way their potentials are that high they reach it in their early 20s. But alas this is OP, and Oda wants to end it whilst they're still young. Thus he makes them as strong as need be. Sanji hasnt trained on-panel ever, yet he is ever-growing with new feats every few chaps. Theres nothing realistic about any of this. Its a damn fictional manga ffs lol. A badly written one at that.