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.
POL demonstrated the greatest increase in VO2peak (+6.8 ml·min·kg−1 or 11.7%, P < 0.001), time to exhaustion during the ramp protocol (+17.4%, P < 0.001) and peak velocity/power (+5.1%, P < 0.01)... With the exception of slight improvements in work economy in THR, both HVT and THR had no further effects on measured variables of endurance performance (P > 0.05).
Why this rating
Randomized controlled trial with well-trained athletes, clear protocols, and statistically significant results, though limited to 9 weeks.
Source
Polarized training has greater impact on key endurance variables than threshold, high intensity, or high volume training
Thomas Stöggl et al. · Frontiers in Physiology · 2014
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