Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Jul 31;9(3):e001601.
doi: 10.1136/bmjsem-2023-001601. eCollection 2023.

Exercise intensity domains determined by heart rate at the ventilatory thresholds in patients with cardiovascular disease: new insights and comparisons to cardiovascular rehabilitation prescription recommendations

Juliana Goulart Prata Oliveira Milani  1   2 , Mauricio Milani  1   2 , Graziella França Bernardelli Cipriano  1   3 , Dominique Hansen  2   4 , Gerson Cipriano Junior  1
Affiliations

Exercise intensity domains determined by heart rate at the ventilatory thresholds in patients with cardiovascular disease: new insights and comparisons to cardiovascular rehabilitation prescription recommendations

Juliana Goulart Prata Oliveira Milani et al. BMJ Open Sport Exerc Med. .

Abstract

Objectives: To compare the elicited exercise responses at ventilatory thresholds (VTs: VT1 and VT2) identified by cardiopulmonary exercise testing (CPET) in patients with cardiovascular disease (CVD) with the guideline-directed exercise intensity domains; to propose equations to predict heart rate (HR) at VTs; and to compare the accuracy of prescription methods.

Methods: A cross-sectional study was performed with 972 maximal treadmill CPET on patients with CVD. First, VTs were identified and compared with guideline-directed exercise intensity domains. Second, multivariate linear regression analyses were performed to generate prediction equations for HR at VTs. Finally, the accuracy of prescription methods was assessed by the mean absolute percentage error (MAPE).

Results: Significant dispersions of individual responses were found for VTs, with the same relative intensity of exercise corresponding to different guideline-directed exercise intensity domains. A mathematical error inherent to methods based on percentages of peak effort was identified, which may help to explain the dispersions. Tailored multivariable equations yielded r2 of 0.726 for VT1 and 0.901 for VT2. MAPE for the novel VT1 equation was 6.0%, lower than that for guideline-based prescription methods (9.5 to 23.8%). MAPE for the novel VT2 equation was 4.3%, lower than guideline-based methods (5.8%-19.3%).

Conclusion: The guideline-based exercise intensity domains for cardiovascular rehabilitation revealed inconsistencies and heterogeneity, which limits the currently used methods. New multivariable equations for patients with CVD were developed and demonstrated better accuracy, indicating that this methodology may be a valid alternative when CPET is unavailable.

Keywords: Cardiology; Exercise rehabilitation; Exercise testing; Heart disease.

PubMed Disclaimer

Conflict of interest statement

Competing interests: None declared.

Figures

Figure 1
Figure 1
HR at first and second ventilatory threshold (VT1 and VT2) according to obtained percentages of peak oxygen uptake (%VO2peak), peak HR (%HRpeak) or HR reserve (%HRR) and different exercise intensity domains elicited according to cardiovascular rehabilitation guidelines. Data expressed as violin plots for individual values with vertical lines representing median and IQR values. The percentual number on the line above violin plots expresses the distribution of frequency of occurrence of individual responses in correspondence to recommended exercise intensity domains according to each set of guidelines (Brazilian, European and American20). HR, heart rate.
Figure 2
Figure 2
Study flow chart.
Figure 3
Figure 3
Correlations between heart rate at ventilatory thresholds (VTs) and peak heart rate (HR). (A) Correlation for HR at VT1 (expressed as absolute value) and HRpeak; B) correlation for HR at VT1 (expressed as %HRpeak) and HRpeak; C) correlation for HR at VT2 (expressed as absolute value) and HRpeak; D) correlation for HR at VT2 (expressed as %HRpeak) and HRpeak. HRpeak, peak HR; %HRpeak, percentage of HRpeak.
Figure 4
Figure 4
Forecasting accuracy calculated by mean absolute percentage error of exercise prescription using indirect methods for first and second ventilatory thresholds. Gold standard (MAPE equals zero) considered ventilatory thresholds identified by cardiopulmonary exercise testing. Guideline references: Brazilian, European and American. %HRpeak, percentage of peak heart rate, measured or predicted; MAPE, mean absolute percentage error.
See this image and copyright information in PMC

References

    1. Piepoli MF, Hoes AW, Agewall S, et al. 2016 European guidelines on cardiovascular disease prevention in clinical practice: the sixth joint task force of the European society of cardiology and other societies on cardiovascular disease prevention in clinical practice (constituted by representatives of 10 societies and by invited experts): developed with the special contribution of the European Association for cardiovascular prevention & rehabilitation (EACPR). Eur J Prev Cardiol 2016;23:1–96. 10.1177/2047487316653709 - DOI - PubMed
    1. Carvalho T, Milani M, Ferraz AS. Diretriz brasileira de reabilitacao cardiovascular - 2020. Arq Bras Cardiol 2020;114:943–87. 10.36660/abc.20200407 - DOI - PMC - PubMed
    1. Mezzani A, Hamm LF, Jones AM, et al. Aerobic exercise intensity assessment and prescription in cardiac rehabilitation: a joint position statement of the European Association for cardiovascular prevention and rehabilitation, the American Association of cardiovascular and pulmonary rehabilitation and the Canadian Association of cardiac rehabilitation. Eur J Prev Cardiol 2013;20:442–67. 10.1177/2047487312460484 - DOI - PubMed
    1. Fletcher GF, Ades PA, Kligfield P, et al. Exercise standards for testing and training: a scientific statement from the American heart association. Circulation 2013;128:873–934. 10.1161/CIR.0b013e31829b5b44 - DOI - PubMed
    1. Ambrosetti M, Abreu A, Corra U, et al. Secondary prevention through comprehensive cardiovascular rehabilitation: from knowledge to implementation. Eur J Prev Cardiol 2020;28:460–95. - PubMed

LinkOut - more resources