Changes in cycling efficiency during a competitive season
Participants
n=14 trained cyclists (34 ± 8 yr, 74.3 ± 7.4 kg, Wmax 406 ± 43 W, VO₂max 59.5 ± 3.8 mL/kg/min), at least 3 yr competitive experience.
Protocol
Five laboratory tests over a competitive season: lactate threshold (LT), OBLA, VO₂max, maximal minute power (Wmax) and gross efficiency (GE); repeated-measures ANOVA and Pearson correlations with training time in intensity bands.
Key Findings
GE changed significantly across the season (P < 0.05): 19.6% -> 20.6% over the pre-competition phase, held at 20.3% through the main competitive phase (n.s. vs 20.6%), then fell to 19.4% in the post-competitive phase (P < 0.05). The seasonal swing is about one GE percentage point (arithmetic on 19.6/20.6/19.4).
Pre-competition GE gains were related to total training time (r = 0.84) and to time spent above OBLA intensity (r = 0.80).
Riders who spent the most time between LT and OBLA (r = 0.87; P < 0.05) best maintained GE through the competitive phase; an inverse relationship linked GE change to the percentage change in training below LT over that phase.
Conclusion: GE tracks the volume AND intensity of training conducted — it is not a fixed trait within a season.
Practical Application
Hopker et al. 2009 (n=14 trained cyclists, 5 tests in one season): gross efficiency rose from 19.6% to 20.6% in the build-up, held around 20.3% through racing and fell back to 19.4% afterwards; the gain tracked total training time (r = 0.84) and time above OBLA (r = 0.80). Efficiency is a seasonal variable in its own right, gained with load and lost when it drops.
The riders who kept GE through the season were those with the most time between LT and OBLA (r = 0.87); shifting the mix toward sub-LT riding in the race phase went with GE loss.
Not from this paper; the base's own practice: keep some structured cycling-specific volume in the off-season to defend the GE gained; a pure cross-training off-season is the pattern this cohort's post-competitive drop warns about.
Inference, not tested: GE and VO₂max/FTP need not move together — track GE separately when a lab test is available.
Limitations
Observational, no controlled experimental manipulation
n=14, single cohort, no control group
"Competitive season" is sport- and discipline-dependent — generalise with care
How this entry was checked and changed
Why this level
regraded 2026-09-27 from B+: small observational cohort, n=14
Content correction 2026-09-27
Level B+ -> B: small observational cohort, n=14. Tier 2-3 -> 2 (VO₂max 59.5).
"~1-2% absolute GE" replaced by the abstract's values (19.6 -> 20.6 -> 20.3 -> 19.4%); added n=14, the cohort description and the training-time correlations (r = 0.84, 0.80, 0.87). "GE can rise while VO₂max plateaus" downgraded to inference (not in the abstract); off-season advice relabelled as the base's own practice. REF-444 byline 2018 -> 2012.
Cross-reference descriptions checked against the cited entries' current content; wrong years, wrong entries and claims the cited entry does not make were corrected.