Polarized vs. High Intensity Multimodal Training in Recreational Runners.

PURPOSE: This study longitudinally compared changes in running performance (5-km TT) and fitness (VO2max, body composition) between polarized training and CrossFit Endurance© in recreational runners.
METHODS: Participants (N=21) completed 12 weeks of CrossFit Endurance (CFE) or polarized endurance training (POL). Both groups trained 5 d·wk-1. POL ran 5 d·wk-1 while CFE ran 3 d·wk-1 and performed CrossFit© 3 d·wk-1 (run + CF 1 d·wk-1). Intensity was classified as low, moderate, or high (Zone 1, 2, or 3) according to ventilatory thresholds. POL was prescribed greater volume (295±67 min·wk-1), distributed as 85/5/10% in Z1/Z2/Z3. CFE emphasized a lower volume (110±18 min·wk-1) distribution of 48/8/44%.
RESULTS: POL ran 283±75.9 min·wk-1 and 47.3±11.6 km·wk-1, both exceeding the 117±32.2 min·wk-1 and 19.3±7.17 km·wk-1 in CFE (p<0.001). The POL distribution (74/11/15%) had greater total and percent Z1 (p<0.001) than CFE (46/15/39%), which featured higher percent Z3 (p<0.001). TT improved -93.8±40.4s (-6.21±2.16%) in POL (p<0.001) and -84.2±65.7s (-5.49±3.56%) in CFE (p=0.001). Body composition improved by -2.45±2.59 %fat in POL (p=0.02) and -2.62±2.53% CFE (p=0.04). The magnitude of improvement was not different between groups for TT (p=0.79) or BC (p=0.88). Both groups increased VO2 max (p≤0.01), but with larger magnitude (p=0.04, d=0.85) in POL (4.3±3.6 ml·kg·min-1) than CFE (1.78±1.9 ml·kg·min-1).
CONCLUSIONS: Recreational runners achieved similar improvement in 5-km performance and body composition through polarized training or CFE, but POL yielded a greater increase in VO2 max. Extrapolation to longer distances requires additional research.

RCT Entities:   Population Interventions Outcomes