[oh_sigh]

Can humans even effectively learn/train @ 80-100 hrs/week? 90 hrs/week + 8 hours sleeping(all-in) leaves 3 hours/day for "personal" non-(work|sleep). Or, alternatively, it leaves 1 full day free per week, with 6 days where there is only 1 hour/day for personal activities.

[s1artibartfast]

It depends on what you mean by effectively. Slaves routinely worked sun up to sun down 6 days a week. Long work weeks are common in some developing countries now.