Convenient and precise heart rate measurement in everyday life
The cosinuss° One measures the heart rate with high accuracy, which has been already validated in several medical and sports medicine studies (please see: Heart Rate). But what about in day-to-day life? How does the cosinuss° One behave during daily activities such as walking, cycling, chewing or talking? Wearing a chest strap in everyday life is certainly not the first choice of many. In order to investigate the accuracy and validity of the heart rate mesaurements of cosinuss° One in everyday life, we conducted a study, in which various everyday movements were examined.
Test protocol and execution
cosinuss° One was tested during activities such as slow and fast walking, slow and fast treadmill running and cycling on an ergometer with different intensities. In addition, talking, chewing, sitting and standing were examined. A total of 16 persons participated the study, which took place in the cosinuss° laboratory, under controlled conditions, to ensure the comparability of the results. A chest strap (Polar H7) was used as a reference. The cosinuss° LabClient served as a Bluetooth receiver for the °One and also for the chest strap, in order to record synchronized data from both measuring devices. The trigger function of the LabClient makes it possible to mark time points and periods in the recordings, so that we could differentiate between specific activities and phases.
The cosinuss° One enables measurement accuracy equivalent to gold standard chest strap
The comparison between the reference chest strap and the °One heart rate measurements during active movements demonstrates large overlap (Figure 1). Recordings started with a short resting phase while sitting (rest), followed by slow walking (walking_2) and then fast walking (walking_4) and subsequently by slow and fast running (running_7 and running_9, respectively) on the treadmill. After changing from the treadmill to the cycling ergometer, two different intensities of cycling were applied. Finally, recovery phase was recorded for each participant, to observe the decrease to the resting heart rate. The cosinuss° One heart rate measurement is shown in blue and the reference chest strap in red. Due to the high overtuning between °One and the chest strap, the red line is hardly visible.
Figure 1: Comparison between the cosinuss° One and the chest strap heart rate measurements during active movements (from 16 participants).
Heart rate measurements during the activities of sitting, chewing, speaking and standing also show a good match between the chest strap and the cosinuss° One (Figure 2), although the interpersonal variance was large particularly during chewing and speaking. The signal quality of the heart rate decreases significantly during these two activities, leading to unreliable results in individual cases.
Figure 2: Comparison between the cosinuss° One and the chest strap heart rate measurements (from 16 participants).
Conclusion
The examples underline the high accuracy and validity of the °One heart rate measurements during everyday movements. The °One is therefore an ideal companion in everyday life, whether you are walking, cycling or reading the newspaper.
