Measurements were performed using the
SOMNOtouch™ (SOMNOmedics
®, Randersacker, Germany) at four time points: once at Pre and once at the end of each month of HDBR (M1, M2, and M3). This system allows a beat-by-beat estimation of blood pressure based on the measurement of the pulse transit time (Bilo et al., 2015 (
link)).
The
SOMNOtouch™ was placed a few hours (0–2 h) before bedtime and was removed the following evening. Brachial blood pressure for calibration was measured using an Omron
automatic blood pressure monitor. Cardiovascular variables (R-R interval, SBP, and DBP) and activity (wrist monitor) were recorded continuously for 21 h, from 21:00 to 18:00. The average values per hour were extracted.
To calculate “day” and “night” mean values, the 23:00–05:00 period was considered “night,” and 07:00–17:00 was considered “day.” The 22:00 and 06:00 points were excluded from the averages to avoid artifacts during these transition periods.
Robin A., Wang L., Custaud M.A., Liu J., Yuan M., Li Z., Lloret J.C., Liu S., Dai X., Zhang J., Lv K., Li W., Gauquelin-Koch G., Wang H., Li K., Li X., Qu L., Navasiolava N, & Li Y. (2022). Running vs. resistance exercise to counteract deconditioning induced by 90-day head-down bedrest. Frontiers in Physiology, 13, 902983.