ACUTE EFFECT OF SMARTPHONE APPLICATION GUIDED BREATHING ON BLOOD PRESSURE, BAROREFLEX SENSITIVITY, AND AORTIC STIFFNESS
Joseph D. Vondrasek1, Brett L. Cross1,,2, Gregory J. Grosicki1, Andrew A. Flatt1. 1Georgia Southern University, Savannah, GA. 2Florida State University, Tallahassee, FL.
BACKGROUND: Blood pressure (BP), baroreflex sensitivity (BRS), and central arterial stiffness (carotid-femoral pulse wave velocity, cf-PWV) are health markers associated with cardiovascular disease risk, and cost-effective methods for optimizing these metrics are desirable. Previously, device-guided paced breathing improved BP, BRS, and cf-PWV, but there may be a cost barrier for some consumers. Free smartphone applications (app) with breathing guidance are widely available and may be a cost-effective means to improve BP, BRS, and cf-PWV. Therefore, we evaluated the acute cardiovascular effects of paced breathing using a cost-free app. METHODS: Twenty-one apparently healthy young adults (13M:9F; Age: 23.1 ± 3.7 yrs; body mass index: 23.5 ± 2.0 kg/m2) performed 10 min of spontaneous breathing (CTRL) and 10 min of app-guided paced (PACE) breathing (supine, 6 breaths∙min-1; 5-s inhale, 5-s exhale) in a counterbalanced order. Ten min of stabilization preceded both conditions, and 3 min of standing served as a washout period between conditions. BP and cf-PWV were measured immediately before and after each condition using a SphygmoCor XCEL. During each condition, R-R intervals were recorded via electrocardiography and beat-to-beat BP via a continuous non-invasive arterial pressure monitor. Cardiovagal BRS was determined using the sequence method (≥ 3 cycles, ± 4 ms, ± 1 mmHg, R2 ≥ 0.85). Two-way repeated measures analysis of variance was used to assess pre- and post-condition measures (BP, cf-PWV), and a paired t-test was used to compare BRS between conditions. RESULTS: There were no time×condition interactions for systolic or diastolic BP (P > 0.05). There was a time×condition interaction for cf-PWV (P = 0.02). Cf-PWV increased (P = 0.018, d = 0.25) from pre-PACE (5.8 ± 0.8 m/s) to post-PACE (6.0 ± 0.7 m/s), whereas no change (P > 0.05, d = 0.00) occurred from pre-CTRL (5.7 ± 0.7 m/s) to post-CTRL (5.7 ± 0.7 m/s). A total of 14/22 participants met criteria for BRS, which was higher (P = 0.02, d = 0.94) during PACE (26.4 ± 10.8 ms/mmHg) vs. CTRL (19.3 ± 7.5 ms/mmHg). CONCLUSIONS: In young adults, paced breathing guided by a free app promoted acute increases in BRS while minimally affecting BP. Arterial stiffness statistically increased during PACE, but the magnitude of change was well below previously reported clinical meaningfulness (± 0.5 m/s) or minimal detectable change thresholds (± 0.411 m/s).
Vondrasek, JD; Cross, BL; Grosicki, GJ; and Flatt, AA
"ACUTE EFFECT OF SMARTPHONE APPLICATION GUIDED BREATHING ON BLOOD PRESSURE, BAROREFLEX SENSITIVITY, AND AORTIC STIFFNESS,"
International Journal of Exercise Science: Conference Proceedings: Vol. 16:
2, Article 271.
Available at: https://digitalcommons.wku.edu/ijesab/vol16/iss2/271