Drawing from life is really key to become better drawers for illustrators, animators and painters. To me it’s a basic fundamental that often gets over looked by some people. It’s like not knowing the words of a song before you sing. When life drawing I prefer starting with 1,2 and 5 min poses for quick gestural poses and then working up to 10,15,20 and 30 min poses. If I am drawing or painting for more polished work however, its nice to have longer poses, a 1 hour or even the academic traditional long sessions like a 3-6 hr pose.