Different approaches to quantify moderate to vigorous physical activity yielded large discrepancies over 3 weeks, ranging from a mean of 448 minutes (novel equation) to 5753 minutes (%HRpeak).
Observational (n=24)
How do different approaches to quantifying moderate to vigorous physical activity compare in patients in primary and secondary CVD prevention?
Different approaches for deriving moderate to vigorous physical activity based on heart rate and accelerometry show considerable discrepancies, highlighting the need for standardized measurement methods in CVD prevention.
Abstract Introduction Physical inactivity is a prevalent risk factor for cardiovascular disease (CVD), the leading cause of death. Regular physical activity is an important lifestyle factor for CVD prevention, whereby moderate to vigorous physical activity (MVPA) intensity is particularly beneficial for cardiovascular and general health. The continuous measurement of MVPA under free-living conditions can provide valuable information to guide a patient in their physical activity behaviour. However, there are different approaches to measuring and categorising MVPA under free-living conditions. Purpose The objective of this study was to compare four approaches to derive the amount of MVPA from continuous heart rate and accelerometry measurements under free-living conditions. Methods As part of a larger study, 24 patients in primary and secondary CVD prevention (six using beta blockers) underwent maximal cycle ergometry and wore a heart rate monitor and an wrist-worn accelerometer during waking hours for a period of three weeks. We applied three approaches to derive daily minutes of MVPA from heart rate. Based on European Society of Cardiology guidelines, we calculated MVPA by heart rate above 55% of the maximum heart rate (%HRpeak) and by heart rate above 40% of the heart rate reserve (%HRR). As the third approach, we used a novel equation that derives heart rate at the first ventilatory threshold from HRpeak and resting heart rate 1. For accelerometry, we applied a validated cut-point for vector counts of 3,941 2. For each patient, we calculated daily minutes of MVPA based on these four approaches. We compared the total amount of MVPA over the three-week period and the daily average according to each approach. All data analyses were conducted in Python Pandas. Results The findings indicate large discrepancies in the proportion of time categorised as MVPA, depending on the approach. The total amount of MVPA over the three-week period was highest when categorised by %HRpeak (mean 5753 minutes, SD 4800, range 1100 - 17725), followed by accelerometry (mean 3980 minutes, SD 1825, range 667 – 6998), categorisation by %HRR (mean 513 minutes, SD 794, range 81-2846), and the novel equation (mean 448 minutes, SD 694, range 71 - 2549). Daily averages per participant are shown in figure 1. Conclusion Different approaches for deriving MVPA based on heart rate and accelerometry show considerable discrepancies. Robust and convenient measurement methods for MVPA under free-living conditions would be helpful to monitor and support physical activity in the primary and secondary prevention of CVD.
Seywald et al. (Wed,) conducted a observational in Cardiovascular disease prevention (n=24). Different approaches to quantify MVPA (%HRpeak, %HRR, novel equation, accelerometry) was evaluated on Total amount of MVPA over the three-week period. Different approaches to quantify moderate to vigorous physical activity yielded large discrepancies over 3 weeks, ranging from a mean of 448 minutes (novel equation) to 5753 minutes (%HRpeak).