"Footballers normally train for an hour and a half, but it doesn't mean they work for an hour and half. Some might be demonstrating a function while the others are watching. And then it's your turn. It's not how long you train, but what you put into it. If you train properly, 35 minutes a day might do. We built Liverpool's training on exhaustion and recovery with little areas of two-a-side, three-a-side and five-a-side in which you work like a boxer, twisting and turning. Training was based on basic skills, control, passing, vision, awareness."
Bill Shankly on training