title: A 'ramp-sprint' protocol to characterise indices of aerobic function and exercise intensity domains in a single laboratory test.
abstract: OBJECTIVE
  The lactate threshold (LT), critical power (CP) and maximum oxygen uptake (VO₂max) together partition exercise intensity domains by their common physiological, biochemical and perceptual response characteristics. CP is the greatest power output attainable immediately following intolerance at VO₂peak, and the asymptote of 3 min all-out exercise. Thus we reasoned that a maximal 'sprint' immediately following standard ramp-incremental exercise would allow characterisation of the three aerobic indices in a single test.
  
  
  METHODS
  Ten healthy men (23 ± 3 year, mean ± SD) performed 9 cycle-ergometry tests on different days: (A) two ramp-incremental tests to intolerance (20 W min(-1)), immediately followed by a 3 min maximal, variable-power effort ramp-sprint test (RST) for LT, VO₂peak and sprint-phase power (SP) determination; (B) four constant-power tests for CP and VO₂max determination; (C) constant-power tests at 10 W below LT, and 10 W below and above SP to verify intensity domain characterisation. Capillary [lactate] and breath-by-breath VO₂ were measured.
  
  
  RESULTS
  Reproducibility of LT, SP and VO₂max measurements between RST repeats was within 5% or less (r ≥ 0.991, p < 0.001). CP (257 ± 46 W) was not different (p = 0.72) from SP (258 ± 42 W). Exercise 10 W below LT and SP resulted in steady state VO₂ and [lactate]. VO₂max (4.0 ± 0.6 L min(-1)), peak [lactate] (11 ± 2 mM) and intolerance were reached 19 ± 5 min into exercise at 10 W above SP.
  
  
  CONCLUSIONS
  These data suggest that the key indices of aerobic function may be accurately and reliably estimated during a single exercise test. This test may provide a basis for simplifying assessment and prescription of exercise training and experimental interventions.
authors.affiliation: School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
authors.forename: Scott R
authors.initials: SR
authors.lastname: Murgatroyd
authors.forename: Lindsey A
authors.initials: LA
authors.lastname: Wylde
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Cannon
authors.forename: Susan A
authors.initials: SA
authors.lastname: Ward
authors.forename: Harry B
authors.initials: HB
authors.lastname: Rossiter
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold; D015444:Exercise; D005080:Exercise Test / Q000379:methods*; D006801:Humans; D008297:Male