Related Experiment Video
Updated: Aug 16, 2025
Using Continuous Data Tracking Technology to Study Exercise Adherence in Pulmonary Rehabilitation
Published on: November 8, 2013
Estimation methods to detect changes in cardiorespiratory fitness due to exercise training and subsequent detraining
Tomoaki Matsuo1,2, Rina So3,4, Fumiko Murai4
1Ergonomics Research Group, National Institute of Occupational Safety and Health, Japan, Kawasaki, Japan. matsuo@h.jniosh.johas.go.jp.
Purpose:
To determine whether estimated maximal oxygen consumption ([Formula: see text]) can detect cardiorespiratory fitness (CRF) changes by behavioral modifications. This study compared changes in measured [Formula: see text]O2max (m[Formula: see text]O2max) through exercise intervention with e[Formula: see text]O2max using a multiple regression model (MRM) and linear extrapolation method (LEM).
Methods:
A cross-sectional analysis involving 173 adults was conducted to establish an MRM by including age, sex, body mass index, questionnaire score, heart rate (HR) from step test, and m[Formula: see text]O2max. Subsequently, 15 men participated in an intervention experiment comprising an 8-week, high-intensity interval training, followed by 8-week detraining, and completed anthropometric measurements, questionnaires, step tests, and m[Formula: see text]O2max tests. m[Formula: see text]O2max changes throughout the intervention were compared to e[Formula: see text]O2max changes calculated using the MRM and LEM. The LEM used the HR during the step test with constant values (predetermined [Formula: see text]O2), such as the Chester step test.
Results:
Inclusion of the step test HR in a questionnaire-based MRM improved the estimation power, although the MRM underestimated higher m[Formula: see text]O2max values. In the intervention, m[Formula: see text]O2max increased by 20.0 ± 14.1% (P < 0.01) and subsequently decreased by 9.5 ± 6.6% (P < 0.01) after exercise training and detraining, respectively. Significant method × time interactions were observed between m[Formula: see text]O2max and e[Formula: see text]O2max in the MRM but not in the LEM, i.e., an apparent systematic error (underestimation of high values) of the MRM was absent in the LEM, although the correlation between m[Formula: see text]O2max and e[Formula: see text]O2max using the LEM was moderate.
Conclusion:
e[Formula: see text]O2max, particularly using the MRM with HR as an explanatory factor, is not an appropriate method for detecting CRF changes along with behavioral modifications.
Clinical Trial Registration:
Registered number, UMIN000041031; Registered date, 2020/07/08; URL, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000046855.
