Fujii K1, Kobayashi M1, Saito T1, Kasahara S1, Shimura T1, Tajima C1, Kurokawa K1, Sakai Y1, Shinohara T2, Usuda S3
1Geriatrics Research Institute and Hospital, Maebashi, Japan, 2Department of Physical Therapy, Faculty of Health Care, Takasaki University of Health and Welfare, Takasaki, Japan, 3Gunma University Graduate School of Health Sciences, Maebashi, Japan
Background: Stroke survivors participate in less physical activity than healthy adults. Physical activity can be measured using wearable monitors, such as pedometers, but it is in fact rarely measured. The intensity of physical activity can be estimated from heart rates and it is an important factor for promoting neuroplasticity and recovery following stroke. Nevertheless, little is known about the intensity at which inpatients with subacute stroke perform physical activity during rehabilitation.
Purpose: We aimed to clarify the intensity of physical activity among inpatients with subacute stroke using heart rate monitors during rehabilitation.
Methods: Heart rates (HR) of 19 inpatients with subacute stroke (mean age, 64.8 ± 10.9 years) during physical therapy were recorded every sixty seconds for three days using an H10 heart rate sensor (Polar Electro Oy, Kempele, Finland). We calculated the maximum HR (HRmax) for each inpatient using the predictive equation, HRmax = 206.9－(0.67*age). The intensity of physical activity was categorized based on the ratio of recorded HR during rehabilitation therapy to the calculated HRmax as very light physical activity (VLPA; HRmax 50%), light physical activity (LPA; HRmax 50% - 63%) and moderate-to-vigorous physical activity (MVPA; HRmax > 63%). We calculated the ratios of the amount of time spent participating in physical activity to that of the total amount of physical activity in a rehabilitation program (%VLPA, %LPA, and %MVPA) for three days and compared these values using Friedman test and post hoc tests. We also investigated relationships between age and %VLPA, %LPA, and %MVPA using Pearson product moment correlation coefficient and Spearman rank correlation coefficients. The intensity of physical activity was compared with sex, diagnosis (hemorrhage/infarction) and walking ability (independence /dependence) using unpaired t-test and Mann-Whitney U tests.
Results: Heart rates were recorded for three days in all patients (57 sessions; n = 19). The mean (± SD) (range) %VLPA, %LPA, and %MVPA were 56.3% ± 28.4% (5.3%-96.8%), 37.0% ± 21.6% (3.2%-71.1%) and 6.8% ± 10.0% (0.0%-36.3%), respectively. Friedman test and post hoc tests showed that %MVPA was significantly lower than %VLPA and %LPA (p 0.01), whereas %VLPA and %LPA did not significantly differ (p = 0.117). Age was not associated with %VLPA (r= -0.309, p = 0.198), %LPA (r = 0.287, p = 0.234), and %MVPA (rs = 0.045, p = 0.856). The intensity of physical activity did not significantly differ according to sex, diagnosis and walking ability.
Conclusion(s): Inpatients with subacute stroke participated in physical activity at very light (HRmax 50%) and light (HRmax 50%-63%) intensity for about 90% of a rehabilitation program, and at moderate-to-vigorous intensity (HRmax > 63%) for > 10% of the program. This comparison of physical activity intensity estimated by measuring heart rate, indicates that HR increases in few inpatients with subacute stroke during physical therapy.
Implications: The duration, intensity and frequency of physical activity should be considered to increase the HR of inpatients with subacute stroke when designing a physical rehabilitation program. Further study is required to determine which factors are associated with increased HR during physical therapy.
Keywords: Inpatients with stroke, Heart rate monitor, Physical activity intensity
Funding acknowledgements: Not applicable
Purpose: We aimed to clarify the intensity of physical activity among inpatients with subacute stroke using heart rate monitors during rehabilitation.
Methods: Heart rates (HR) of 19 inpatients with subacute stroke (mean age, 64.8 ± 10.9 years) during physical therapy were recorded every sixty seconds for three days using an H10 heart rate sensor (Polar Electro Oy, Kempele, Finland). We calculated the maximum HR (HRmax) for each inpatient using the predictive equation, HRmax = 206.9－(0.67*age). The intensity of physical activity was categorized based on the ratio of recorded HR during rehabilitation therapy to the calculated HRmax as very light physical activity (VLPA; HRmax 50%), light physical activity (LPA; HRmax 50% - 63%) and moderate-to-vigorous physical activity (MVPA; HRmax > 63%). We calculated the ratios of the amount of time spent participating in physical activity to that of the total amount of physical activity in a rehabilitation program (%VLPA, %LPA, and %MVPA) for three days and compared these values using Friedman test and post hoc tests. We also investigated relationships between age and %VLPA, %LPA, and %MVPA using Pearson product moment correlation coefficient and Spearman rank correlation coefficients. The intensity of physical activity was compared with sex, diagnosis (hemorrhage/infarction) and walking ability (independence /dependence) using unpaired t-test and Mann-Whitney U tests.
Results: Heart rates were recorded for three days in all patients (57 sessions; n = 19). The mean (± SD) (range) %VLPA, %LPA, and %MVPA were 56.3% ± 28.4% (5.3%-96.8%), 37.0% ± 21.6% (3.2%-71.1%) and 6.8% ± 10.0% (0.0%-36.3%), respectively. Friedman test and post hoc tests showed that %MVPA was significantly lower than %VLPA and %LPA (p 0.01), whereas %VLPA and %LPA did not significantly differ (p = 0.117). Age was not associated with %VLPA (r= -0.309, p = 0.198), %LPA (r = 0.287, p = 0.234), and %MVPA (rs = 0.045, p = 0.856). The intensity of physical activity did not significantly differ according to sex, diagnosis and walking ability.
Conclusion(s): Inpatients with subacute stroke participated in physical activity at very light (HRmax 50%) and light (HRmax 50%-63%) intensity for about 90% of a rehabilitation program, and at moderate-to-vigorous intensity (HRmax > 63%) for > 10% of the program. This comparison of physical activity intensity estimated by measuring heart rate, indicates that HR increases in few inpatients with subacute stroke during physical therapy.
Implications: The duration, intensity and frequency of physical activity should be considered to increase the HR of inpatients with subacute stroke when designing a physical rehabilitation program. Further study is required to determine which factors are associated with increased HR during physical therapy.
Keywords: Inpatients with stroke, Heart rate monitor, Physical activity intensity
Funding acknowledgements: Not applicable
Topic: Neurology: stroke
Ethics approval required: Yes
Institution: Geriatrics Research Institute and Hospital
Ethics committee: Institutional Review Board at the Geriatrics Research Institute and Hospital
Ethics number: 60
All authors, affiliations and abstracts have been published as submitted.
