REF-092 · Joyner & Coyle, 2008 · The Journal of Physiology, Vol. · Paper

Endurance Exercise Performance: The Physiology of Champions

Three determinants (VO2max, lactate threshold, efficiency)

B+moderate evidenceMeasured on a mixed groupWritten before October 2026, being re-checked

Performance Model

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Performance = f(VO2max, lactate threshold, efficiency)

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Model structure (Joyner & Coyle 2008):

VO2max — maximal oxygen consumption
"Lactate threshold" — together with VO2max it determines the performance VO2: the oxygen consumption that can be sustained for a given period of time
Efficiency — the oxygen cost of generating a given running speed or cycling power; it interacts with the performance VO2 to set the speed or power that can be produced at that oxygen consumption

Key Findings

The review covers how these three factors interact, their usefulness as predictors of elite performance, and where knowledge is thin: the physiological determinants of running and cycling efficiency are much less well defined than VO2max and lactate threshold, and information on genetic predisposition to elite performance is surprisingly limited and unclear.

The authors caution that complex motivational and sociological factors also decide who becomes a champion, so elite performance is likely to defy simple reductionist explanation.

Practical Application

Joyner & Coyle 2008 (review): endurance performance is set by three factors — VO2max and the lactate threshold together fix the oxygen consumption you can sustain for the duration (the "performance VO2"), and efficiency converts that oxygen into speed or power; the model explains why athletes with the same VO2max can differ widely in race performance.
Use the model diagnostically: if sustainable fraction of VO2max is already high, further gains must come from raising VO2max or from efficiency; if VO2max is high but the threshold fraction is low, the threshold is the lever. The paper names the levers; it does not prescribe how to train them.
Efficiency is the least understood of the three by the authors' own account, and in practice it is mostly addressed indirectly (not from this paper: heavy strength training improved cycling economy in REF-078 and running economy in REF-072).
Not from this paper; the base's own practice: assess an athlete on all three axes before choosing a block emphasis, rather than defaulting to "more VO2max" or "more threshold".

Limitations

Foundational review from 2008, not a trial: it organises a framework rather than testing it, and the framework has since been extended.
The three-determinant model is incomplete by modern standards — durability is now treated as a fourth dimension (REF-423, SYNTH-32, REF-477), and it is absent here.
Determinants are established mostly in trained male athletes; the relative weight of each varies by event duration, sport and caliber in ways the model does not specify.
Explains variance between athletes better than it predicts improvement within one — a high VO2max does not tell you which lever to pull next.
No prescription follows directly: the model says what matters, not how to train it.
How this entry was checked and changed
Why this level

regraded 2026-09-27 from A: authoritative narrative review from the leading group, not a systematic review or consensus statement

Content correction 2026-09-27
"Practical Example: VO2max ~54 ml/kg/min, %VO2max@LT2 ~97%, economy +4.8% via strength training" and "Strategy Implications: high threshold utilization (97%) → ceiling; primary lever VO2max" -> these were one athlete's own numbers and plan, not content of the paper; removed. The +4.8% belongs to REF-078 and is pointed there.
Added the paper's actual framing: "performance VO2" (VO2max × lactate threshold), efficiency as the converter, efficiency and genetics as the least understood areas, and the authors' caution about non-physiological factors.
Level A -> B+ (narrative review from the leading group); Sport "cycling, strength" -> running, cycling; Practical Application section added.