Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Standard deviation of normal beat‐to‐normal beat intervals (SDNN) and root mean square of successive R‐R interval differences (RMSSD) in the control and sleep deprivation (SD) groups before and after 4‐7‐8 breathing control. Data are presented as mean ± standard deviation. *Significant difference compared with before 4‐7‐8 breathing control (p < 0.05).
