In this episode, Louis discusses the benefits of the 40-20 interval training split, which involves 40 seconds of high-intensity work followed by 20 seconds of rest. He explained that this method is effective in improving aerobic capacity, metabolic health, and work capacity, and can provide similar benefits to steady-state cardio in a shorter time. Louis also highlighted the mental toughness aspect of this training, emphasizing the importance of pacing and learning when to push without redlining. He suggested various ways to implement this training, including using a rower, skier, or kettlebell, and recommended it for athletes preparing for races, Crossfitters, Hyrox athletes, and strength athletes in a cutting phase.