" For example, an optimal exercise week for a very devoted exerciser could include a two-hour hike, another easy cardio session of one hour, two full-body strength-training sessions lasting no more than 30 minutes each, a sprint session with an accumulated five minutes of maximum effort, and a challenging “play” day (e.g., a pickup soccer, basketball, or Ultimate Frisbee game). "

― Mark Sisson , The Primal Blueprint: Reprogram Your Genes for Effortless Weight Loss, Vibrant Health, and Boundless Energy