Mixed

Polarized training (POL), characterized by high volumes of low-intensity exercise and short bursts of high-intensity intervals while minimizing time at lactate threshold, produces superior improvements in VO2peak, time to exhaustion, and peak velocity/power compared to threshold, high-intensity interval, or high-volume training in well-trained endurance athletes.

If you are an experienced endurance athlete, stop spending most of your training time at 'moderate' or 'threshold' intensity. Instead, structure your training so that roughly 80% of your time is at a very easy pace (where you can hold a conversation) and 20% is at a very hard pace (high-intensity intervals). Avoid spending significant time at your lactate threshold, as this yields diminishing returns for elite performers. This approach maximizes improvements in your aerobic capacity (VO2peak) and race performance.