Exercise researchers at Johns Hopkins University recently performed a study regarding the effectiveness of using short-term heart rate variability (HRV) as a means to monitor the efficiency and safety of cycling activity. Though it had been previously shown that beat-by-beat heart rate data is a good indicator of physiological stress, the potential value of short-term HRV as an automated assessment of exertion level was unknown. The study was designed as such: subjects were asked to perform a 13-minute cycling exercise on an interactive Biking Exercise program, and HRV data was recorded with an electrocardiogram transmitter. Time periods denoting different levels of exercise before and during the program were classified as “rest,” “highest exertion” and “recovery.” A BIOPAC BN-RSPEC wireless ECG and Respiration transmitter/receiver pair was used to acquire appropriate heart rate data. Data from the wireless ECG amplifier was sampled by an MP150 data acquisition system connected to a standard laptop PC. From each subject, nine sets of ECG data were obtained—three each for rest, highest exertion, and recovery time periods. These data sets were recorded with AcqKnowledge software. Further analysis showed significant differences were found among seven HRV variables between time-domains characterized by differing levels of physical exertion. These data were shown to closely match their predictive model. This allowed researchers to conclude that the HRV coupled to time-domain indices separated by exertion level accurately reflected autonomic balance and stress levels during the exercise program. This suggests HRV data can be used short term to measure the efficacy of home-based exercise programs. BIOPAC Systems offers a variety of solutions for Heart Rate Variability and ECG extraction including wireless, wearable and MRI applications. Use of these physiological parameters can be utilized in further studies, continuing to examine and compare the benefits of home-based cycling and other exercise programs for subjects with differing lifestyles and clinical conditions.
