CLINIMEX Aerobic Fitness Questionnaire: Proposal and Validation

Abstract

Background: Cardiorespiratory (aerobic) fitness is strongly and directly related to major health outcomes, including all-cause mortality. Maximum oxygen uptake (VO 2 max), directly measured by maximal cardiopulmonary exercise test (CPET), represents the subject's aerobic fitness. However, as CPET is not always available, aerobic fitness estimation tools are necessary. Objectives: a) to propose the CLINIMEX Aerobic Fitness Questionnaire (C-AFQ); b) to validate C-AFQ against measured VO 2 max; and c) to analyze the influence of some potentially relevant variables on the error of estimate. Methods: We prospectively studied 1,000 healthy and unhealthy subjects (68.6% men) aged from 14 to 96 years that underwent a CPET. The two-step C-AFQ describes physical activities with corresponding values in metabolic equivalents (METs)-ranging from 0.9 to 21 METs. Results: Application of C-AFQ took less than two minutes. Linear regression analysis indicated a very strong association between estimated (C-AFQ) and measured (CPET) maximal METs-r2 = 0.83 (Sy.x = 1.63; p < .001)with median difference of only 0.2 METs between both values and interquartile range (percentiles 25 and 75) of 2 METs. The difference between estimated and measured METs was not influenced by age, sex, body mass index, clinical condition, ß-blocker use or sitting-rising test scores. Conclusion: C-AFQ is a simple and valid tool for estimating aerobic fitness when CPET is unavailable and it is also useful in planning individual ramp protocols. However, individual error of estimate is quite high, so C-AFQ should not be considered a perfect substitute for CPET's measured VO 2 max.

Estimating VO2peak in 18–90 Year-Old Adults: Development and Validation of the FitMáx©-Questionnaire

“…More recently, the CLINIMEX aerobic fitness questionnaire (C-AFQ) was developed, as a questionnaire-based prediction model for CRF. 52 Despite a high correlation with CPET (r=0.91), C-AFQ leaves considerable inaccuracy in the estimation of VO 2max (SEE=5.39 mL·kg −1 ·min −1 ). Compared to the original C-AFQ study, correlation, SEE and bias with LoA are better for the FitMáx in the current study population.…”

“…Compared to the original C-AFQ study, correlation, SEE and bias with LoA are better for the FitMáx in the current study population. 52 Moreover, an interview was used to complete the C-AFQ in the validation study, this could have led to a high correlation (r=0.91). This phenomenon is also seen in the validation of the DASI.…”

Estimating VO2peak in 18-91 year-old adults: Development and Validation of the FitMáx© - Questionnaire

“…More recently, the CLINIMEX aerobic fitness questionnaire (C-AFQ) was developed, as a questionnaire-based prediction model for CRF. 34 Despite a high correlation with CPET (r=0.91), the C-AFQ leaves considerable inaccuracy in the estimation of VO 2max (SEE= 5.39 ml·kg -1 ·min -1 ). Compared to the original C-AFQ study, correlation, SEE and bias with LoA are better for the FitMáx in the current study population.…”

“…Compared to the original C-AFQ study, correlation, SEE and bias with LoA are better for the FitMáx in the current study population. 34 Moreover, an interview was used to complete the C-AFQ in the validation study, this could have led to a high correlation (r=0.91). This phenomenon is also seen in the validation of the DASI.…”

Physical Activity, Exercise and Sport: A Five-Star Path for a Better Cardiovascular Health

“…Two of these papers make very useful and practical contributions to those working with exercise in their daily practice. In one of these, the authors discuss the proposal and validation of a simple questionnaire for estimating aerobic fitness, 13 and the second one proposes aerobic reference standards derived from a large sample of Brazilian adults.…”