ISSN:
1439-6327
Keywords:
Respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio
;
Incremental exercise
;
Treadmill
;
Maximum oxygen uptake
;
Prediction
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary The purpose of this study was to define carefully the dynamic relationship between oxygen uptake (as% $$\dot V_{O_{2\max } }$$ ) and the respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio (R) during maximum progressive treadmill exercise in trained and untrained men, and to determine if this relationship could be used to predict $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ . Respiratory gases were continuously monitored and the % $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ /R time profile calculated at 15 sec intervals over the final 5 min of each test. Young sedentary men (controls,n = 122) and over −60y sedentary men (n = 30) shared the same % $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ /R relationship but the latter group had lower R values at $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ (1.06±0.03 vs 1.08±0.03,P〈0.01) than controls. Endurance trained men (n = 45) had a lower % $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ /R relationship and higher R at $$\dot V_{O_{2\max } }$$ (1.11±0.02,P〈 0.001), team athletes (n = 98) had a lower% $$\dot V_{O_{2\max } }$$ /R relationship but lower R at $$\dot V_{O_{2\max } }$$ (1.06±0.03,P〈0.001) and the weight trained (n = 19) had a higher% $$\dot V_{O_{2\max } }$$ /R relationship and lower R at $$\dot V_{O_{2\max } }$$ (1.01±0.02,P〈 0.001) all compared to controls. From the % $$\dot V_{O_{2\max } }$$ /R time profile, the following formulae were devised for the estimation of $$\dot V_{O_{2\max } }$$ ( $$\dot V_{O_{2\max } }$$ R): Young Sedentary, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (3.000 −1.874 R); Over −60y Sedentary, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (3.457-2.345 R); Endurance Trained, $$\dot V_{O_{2\max } }$$ = $$\dot V_{O_2 }$$ R (1.980–0.912 R); Team Athletes, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (2.805−1.726 R); Weight Trained, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (4.236−3.191 R). Comparison of recorded $$\dot V_{O_{2\max } }$$ and the estimated $$\dot V_{O_{2\max } }$$ R values showed no significant differences in any of the groups examined (r = 0.89–0.90,p〈 0.001). These results suggest the R response to maximum incremental exercise may be influenced by different types of physical training, and that specific formulae derived from the % $$\dot V_{O_{2\max } }$$ /R relationship can provide a precise estimate of $$\dot V_{O_{2\max } }$$ for individuals.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01075993
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