"When we take a look at some of the most elite musicians in the world, they not necessarily practice more but instead, they practice intentionally. They spend their time to focus on the hardest task and spread their energy evenly. Instead of spending their energy over the whole day, they have intense periods of work followed by breaks. They rely on habit and strictly disciplined scheduling rather than rely on willpower. Some studies showed that the most elite violinists in the world commonly followed 90-minute intense work with a 15-20 minute break afterward." - Monster Box