The effect of training volume and intensity on competitive cyclists' efficiency
Participants
n=29 endurance-trained competitive male cyclists.
Protocol
Three lab visits over 12 weeks (cycling efficiency and VO₂max at each). After test 1, random split into group A (prescribed specific high-intensity sessions for the first 6 weeks) and group B (restricted in intensive work for the first 6 weeks, then allowed high-intensity training in the second 6 weeks).
Key Findings
Gross efficiency rose only after the high-intensity block, in whichever group did it: group A +1.6 ± 1.4% (p < 0.05) in weeks 1-6 while restricted group B did not change (+0.1 ± 0.7%); then group B +1.4 ± 0.8% (p < 0.05) in weeks 7-12 once it trained hard, while group A did not change further (+0.4 ± 0.4%).
Delta efficiency did not change significantly in either group.
Authors' conclusion: GE is increased following high-intensity training in competitive male cyclists over 12 weeks.
The abstract does not test a high-volume/low-intensity arm as an active alternative — the "restricted" phase was the control, and it produced no GE change.
Practical Application
Hopker et al. 2010 (n=29 competitive cyclists, randomized): gross efficiency improved by 1.4-1.6% only during the 6 weeks that included prescribed high-intensity sessions; restricting intensity produced no change (+0.1 ± 0.7% in group B's restricted first 6 weeks). Group A's +0.4 ± 0.4% is its later 6 weeks, after the prescribed block — no further gain, not an intensity-restricted phase.If efficiency is a target, the stimulus this study supports is high-intensity work on top of the riders' normal training, not low-intensity volume alone.
Companion result: in-season GE also tracked time above OBLA in the same lab's cohort (REF-487) — the two papers point the same way.
Inference, not tested: GE gains plateaued once the block ended (+0.4% in group A afterwards), so efficiency may need a repeated stimulus rather than a one-off block.
Limitations
Randomized, but the control was "restricted intensity", not a matched high-volume programme — the study does not show that volume cannot raise GE, only that it did not here
n=29, male only; training outside the prescribed sessions not described in the abstract
Session content and volume of the high-intensity work not given in the abstract; no dose-response
How this entry was checked and changed
Content correction 2026-09-27
Direction reversed: the entry said both low-intensity volume and high-intensity training improved GE and "no single intensity is responsible"; the abstract shows GE rose only after the high-intensity block in each group (+1.6% / +1.4%) and did not change when intensity was restricted (+0.1% / +0.4%). DE unchanged.
Practical advice "reject the GE-specific zone mindset" and "volume-driven GE via Z2 is sound for masters" removed as contradicting the paper; replaced with the abstract's finding. Added n=29, the randomized sequential design and the 12-week timeline. Type corrected from "observational" to randomized intervention.
Cross-references to duplicate stubs repointed to their canonical entries (REF-085->REF-303); the stubs were emptied on 2026-09-27.
2026-10-01: Practical Application corrected from the entry's own Key Findings: '+0.4%' is group A's later 6 weeks (no further change after the high-intensity block), not an intensity-restricted phase; only group B's first 6 weeks (+0.1 ± 0.7%) were restricted.