Students are typically young, and make up for their lack of experience with the energy to work longer. Not necessarily more productively--I've certainly seen people with very counter-productive intense study habits that didn't seem to help them much.

Long, sustained hours are more of a problem; in the US we routinely overwork doctors to the point of risking deadly error--in part because the standards of long hours during residencies were developed by William Stewart Halsted, a cocaine addict who worked 100+ hours per week.

> Students studying for selective examinations (medicine, law, maths) routinely work more than 10 hours a day.

Yes, for a little bit. But one thing I've consistently noticed is they're operating on borrowed time. Once the exam passes and the semester is over, they go into full burn-out mode. Now they're not even doing their laundry, let alone studying medicine.

Human productivity is incredibly fickle. We can be pushed really, really far, but we have to pay an immense debt.

Studying for an exam is a short term, intense, focus with a defined end date. Once the exam is over it's over you get your reward, you rest, and then you're on to something new. It's not comparable to the decades long treadmill that is a career.

Not sure why medicine has such a cult of personality around it, people in that field are glorified flowchart operators.

Doctors can pull a 10 hour shift for the same reason a call center worker can do the same thing. They aren’t doing deep knowledge work. The people actually doing the knowledge work are at research universities setting up controlled trials, running simulations, and putting out papers.