Which Training Intensity Distribution Intervention will Produce the Greatest Improvements in Maximal Oxygen Uptake and Time-Trial Performance in Endurance Athletes? A Systematic Review and Network Meta-analysis of Individual Participant Data
IPD network meta-analysis of 13 studies (348 endurance athletes) found no overall VO2max or time-trial difference between polarized and pyramidal training intensity distributions, but a significant subgroup interaction suggested competitive athletes may gain more VO2max with polarized models while recreational athletes trended toward pyramidal distributions.
Design
SR + IPD NMA; Medline + SPORTDiscus to 11 Feb 2024; 13 studies, 348 athletes (296 male / 52 female); recreational n = 150, competitive n = 198; VO₂max and time-trial (TT) endpoints.
Headline contrasts (heart-rate zone quantification)
- POL vs PYR: VO₂max SMD = −0.06 (p = 0.68); TT SMD = −0.05 (p = 0.34) — interpreted as no pooled difference between polarized and pyramidal distributions in the primary models.
- POL vs other TID nodes: no statistically significant pooled differences reported in abstract summary.
Performance-level interaction (subgroup)
Recreational vs competitive athletes: significant VO₂max response difference for POL vs PYR (SMD = −0.63, p < 0.05)—abstract frames competitive athletes as potentially benefiting more from POL, and recreational athletes from PYR.
Evidence hygiene
TID labels depend on how zones were operationalised across contributing trials—this is endurance-sport physiology, not a medical training prescription for disease cohorts.
Publication
Rosenblat MA, Watt J, Arnold J, et al. Sports Med. 2025 Mar;55(3):621-639. PMID 39888556.
Outcomes
- Polarized vs pyramidal TID: pooled VO2max SMD ≈ −0.06 (p = 0.68) and time-trial SMD ≈ −0.05 (p = 0.34)—no significant overall difference.
- Subgroup (recreational vs competitive athletes): VO2max response differed for POL vs PYR (SMD = −0.63, p < 0.05)—competitive athletes trended toward larger gains with polarized training; recreational toward pyramidal.