Block periodisation gives at most a small advantage in VO2max and maximal power over traditional training, and no clear performance advantage when load is matched
Interpretation
Early small trials in trained male cyclists (19 and 15 riders) found larger VO2max gains with block periodisation (Rønnestad 2014a, 2014b). A meta-analysis of 6 pooled trials (107 mostly male athletes) found small advantages for VO2max (SMD 0.40) and maximal power (SMD 0.28), with prediction intervals crossing zero and low study quality (Mølmen 2019). The largest load-matched trial, 30 trained cyclists, found no difference in time-trial gains (Almquist 2022). Physiological markers modestly favour blocks; performance outcomes don't. Much of the evidence comes from one research group, and none from triathletes.
Practical implication
Total load, progression, consistency and recovery matter more than block versus traditional structure. Short concentrated blocks in one sport, followed by easier weeks, are a reasonable tool for variety or refreshing a stalled sport, but are not a proven advantage for triathletes, who must absorb three sports; extrapolated from cyclists and skiers.
Sources
7 sources, independently verified.
Describes block periodisation as consecutive specialised blocks of highly concentrated workloads targeting few abilities, and lists limitations of traditional mixed periodisation: conflicting responses, excessive fatigue, insufficient stimulus from medium and low loads, and difficulty producing multiple peaks. Conceptual review, not a trial.
Argues that periodisation models share historical assumptions that are no longer scientifically justified, that individual training responses vary widely, and that planning should be flexible and context-specific rather than rule-based.
Four weeks with similar total high- and low-intensity volume: block group (5 interval sessions in week 1, then 1 per week) improved VO2max 4.6%, peak power 2.1% and power at 2 mmol/L lactate 10%; traditional group (2 per week) showed no significant changes; VO2max gain greater with block. Small samples; published online 2012.
Volume-matched 12 weeks: block group (5 interval sessions every fourth week, 1 per week otherwise) increased VO2max 8.8% vs 3.7% with 1 session per week; power at 2 mmol/L 22% vs 10% (P = 0.054); moderate effect sizes (0.62-1.12) favouring block for several indices including 40-minute all-out power. Very small groups; published online 2012.
20 studies reviewed; 6 parallel-group trials (107 participants) pooled. Block vs traditional: VO2max SMD 0.40 (95% CI 0.02-0.79), maximal power SMD 0.28 (0.01-0.54); prediction intervals crossed zero; performance not pooled. Mean PEDro 3.7/10. Short, mostly pre-season interventions; several trials from the authors' own group.
Load-matched 12 weeks (same number of high-, moderate- and low-intensity sessions; ~92% adherence): no group difference in 5-min (~+9% pooled) or 40-min (~+8%) time-trial power, maximal power (~+6%) or power at 4 mmol/L (~+10%); VO2peak unchanged. Traditional group had larger capillary gains, block group larger red cell volume gain. Performance analysed in 11 block and 15 traditional riders.
Case study comparing two seasons of one world-class female cross-country skier: total load did not differ; the block season (seven high-intensity blocks of 7-11 days) had fewer hours (15 vs 18 h/week), fewer moderate sessions (13 vs 38 per year) and more high-intensity sessions (157 vs 77). Both seasons were successful. Single elite athlete.