Abstract
Previous studies have shown that a walking cadence of 100 steps/min corresponds with moderate physical activity intensity among the general population. However, less is known about the cadence-intensity relationship in individuals with low cardiorespiratory fitness (CRF) due to chronic disease.
PURPOSE: To explore cadence thresholds for absolutely-defined moderate to vigorous intensity (≥3 metabolic equivalents [METs]) in adults with chronic heart failure (HF).
METHODS: Adults with HF (n = 16, mean age = 60.3 yrs) completed treadmill-based cardiopulmonary exercise tests (CPET) across multiple time points (median = 2.5 per participant) while wearing ActiGraph-GT9X accelerometer on the ankle and waist. Cadence (steps/min) at both sites was recorded, and the corresponding intensity level (METs) was measured using indirect calorimetry throughout the CPET. A quadratic regression model was established to estimate cadence thresholds at 3 METs for each test. For participants with multiple CPETs, the estimated cadence thresholds were averaged across tests. Descriptive statistics including mean, standard deviation (SD), and range were estimated. A paired-sample t-test was conducted to compare the estimated cadence thresholds between the ankle and waist. To investigate factors influencing variability in the estimated cadence thresholds between sites, a linear regression analysis was performed with V̇O2 peak as the independent variable and the absolute difference in cadence (ankle-waist) as the dependent variable.
RESULTS: Ankle-based cadence corresponding to 3 METs averaged 85.4 steps/min (SD = 12.8; range = 59.5-101.3 steps/min), while waist-based cadence was significantly lower, with a mean of 65.5 steps/min (SD = 12.9; range = 37.9-88.8 steps/min), as determined by a paired-sample t-test (p < .001). The linear regression analysis demonstrated a significant relationship between V̇O2peak and the cadence difference (p = 0.0074), with V̇O2 peak explaining 46% of the variability in cadence difference.
CONCLUSION: Adults with HF achieved moderate-intensity walking at a lower cadence than the 100 steps/min threshold established for healthy adults, highlighting the need for tailored cadence guidelines for this clinical population.