ORIGINAL ARTICLES   

The Journal of Sports Medicine and Physical Fitness 1999 September;39(3):202-6

Copyright © 2000 EDIZIONI MINERVA MEDICA

lingua: Inglese

Reproducibility of the oxygen uptake efficiency slope in normal healthy subjects

Baba R., Kubo N., Morotome Y., Iwagaki S.

Tokai University School of Physical Education and Research Institute of Sports Medicine, Hiratsuka, Kanagawa, Japan

Back­ground. To elu­ci­date the inter­test agree­ment of the oxy­gen ­uptake effi­cien­cy ­slope (­OUES) in com­par­i­son ­with ­those of the max­i­mal oxy­gen ­uptake (V.O2max) and the ven­til­a­to­ry anaer­o­bic thresh­old (VAT).
Meth­ods. Experi­men­tal ­design: A com­par­a­tive ­study. Set­ting: Insti­tu­tion­al prac­tice. A ­total of 19 ­healthy vol­un­teers under­went two ses­sions of max­i­mal exer­cise test­ing ­with an inter­val of no ­more ­than 7 ­days. The test­ing was con­duct­ed on a ­cycle ergom­e­ter ­with the ­work ­rate ­increased by ­either 20, 30, or 40 ­Watts (W)/min so ­that the sub­ject ­would ­reach exhaus­tion with­in 9 to 12 min of exer­cise. VAT was ­defined as the lev­el of oxy­gen ­uptake (V.O2) at ­which ­either an ­increase in the ven­til­a­to­ry equiv­a­lent for oxy­gen with­out a con­com­i­tant ­increase in the ven­til­a­to­ry equiv­a­lent for car­bon diox­ide or a ­change in the ­slope of the lin­e­ar rela­tion­ship ­between car­bon-diox­ide pro­duc­tion (V.CO2) and V.O2 ­occurred. ­OUES was deter­mined by the fol­low­ing equa­tion: V.O2=a log­V.E+b, ­where V.E was min­ute ven­ti­la­tion and “a” was the ­OUES. Inter­test repro­du­cibil­ity was ­assessed by coef­fi­cient of repeat­abil­ity (COR).
­Results. The inter­test repro­du­cibil­ity of V.O2max and ­OUES ­were excel­lent (COR=570 ml/min [16%] and 740 [20%], respec­tive­ly). VAT ­showed ­poor agree­ment ­between the two ­tests (COR=650 ml/min [31%]).
Con­clu­sions. ­Results ­show ­that ­OUES is repro­du­cible and reli­able, sup­port­ing the clin­i­cal use­ful­ness of ­this ­index.