Affiliations: [a] Department of Biomedical Sciences, Missouri State
University, Springfield, MO, USA | [b] Department of Pharmacology and Physiology, Drexel
University College of Medicine, Philadelphia, PA, USA
Note: [] Address for correspondence: Benjamin F. Timson, Ph.D.,
Department of Biomedical Sciences, Missouri State University, 901 South
National Avenue, Springfield, MO 65897, USA. Tel.: +1 417 836 4145; Fax: +1 417
836 5588; E-mail: bentimson@missouristate.edu
Abstract: The purpose of this study was to investigate the plateau occurrence
rate in a cycle ergometer VO_{2max} test in two groups of
subjects, one biased toward low muscle strength relative to cardiovascular
fitness (low muscle strength/cardiovascular fitness ratio) and the other biased
toward high muscle strength relative to cardiovascular fitness. The subjects, 7
collegiate distance runners (DR) and 6 collegiate football linemen (FL),
performed a multiple stage cycle protocol ranging in power output from 60--484
W. VO_{2} was averaged over 15 sec intervals during each
stage. Stage VO_{2} was recorded as the average of the
steady state values on the VO_{2}/time curve. Each subject
performed a VO_{2max} test that consisted of two parts, a
continuous phase and a discontinuous phase. Leg strength was assessed by 1RM
leg press using a hip sled. Plateau occurrence rate was not different between
groups (6/7 DR and 6/6 FL; p = 0.538). Absolute
VO_{2max} was similar in DR and FL
(4.34 ± 0.4 vs. 4.63 ± 0.5 L/min;
p = 0.266), relative VO_{2max} was greater
in DR than FL (65.6 ± 5.6 vs. 38.9 ±
5.5 ml/(kg/min); p < 0.001). Absolute leg strength was greater
in FL than DR (342.0 ± 36.0
vs. 158.1 ± 31.8 kg; p < 0.001), as was
the leg strength to body mass ratio (2.85 ± 0.22
vs. 2.38 ± 0.37; p = 0.034). The leg
strength to cardiovascular fitness ratio, expressed in kg/(ml/min), was greater
in DR than FL (9.02 ± 2.2 vs. 2.46 ±
2.2; p < 0.001). These data suggest that leg strength does not
affect the occurrence rate of a plateau in VO_{2}/power
output curve.
