Prediction of metabolic and cardiopulmonary responses to maximum cycle ergometry: a randomised study.
All of the most widely-cited studies for the prediction of maximum exercise responses have utilized either volunteers or referred subjects. Therefore, selection bias, with overestimation of the reference values, is a likely consequence. In order to establish a set of predictive equations for the gas exchange, ventilatory and cardiovascular responses to maximum ramp-incremental cycle ergometry, this study prospectively evaluated 120 sedentary individuals (60 males, 60 females, aged 20-80), randomly-selected from >8,000 subjects. Regular physical activity pattern by questionnaire, body composition by anthropometry and dual energy X-ray absorptiometry (n = 75) and knee strength by isokinetic dynamometry were also assessed. Previously reported equations typically overestimated the subjects' peak oxygen uptake (p<0.05). Prediction linear equations for the main variables of clinical interest were established by backward stepwise regression analysis including: sex, age, knee extensor peak torque, bone-free lean leg mass, total and lean body mass, height, and physical activity scores. Reference intervals (95% confidence limits) were calculated: some of these values differed markedly from those formerly recommended. The results therefore might provide a more appropriate frame of reference for interpretation of the responses to symptom-limited ramp incremental cycle ergometry in sedentary subjects; i.e. those usually referred for clinical cardiopulmonary exercise tests.
Neder
J A
JA
Dept of Medicine, UNIFESP-EMP, Sao Paulo, Brazil.
Nery
L E
LE
Castelo
A
A
Andreoni
S
S
Lerario
M C
MC
Sachs
A
A
Silva
A C
AC
Whipp
B J
BJ
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D002320:Cardiovascular Physiological Phenomena; D004734:Energy Metabolism / Q000502:physiology*; D016552:Ergometry; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange / Q000502:physiology; D012016:Reference Values; D012680:Sensitivity and Specificity; D012737:Sex Factors
D010100:Oxygen