Skip to main content
. Author manuscript; available in PMC: 2013 Aug 1.
Published in final edited form as: Aging Cell. 2012 May 21;11(4):644–650. doi: 10.1111/j.1474-9726.2012.00825.x

Fig. 1.

Fig. 1

Mean heart rate variability (HRV) in caloric restriction (CR) (age, 51.5 ± 10.8 years) and Western diets (WD) (age, 52 ± 8.9 years) compared with previously published age-related norms. Curves show age-related norms for 24-h standard deviation of normal-to-normal (N-N) intervals in ms (SDNN), 24-h SD of 5-min-averaged N-N intervals (SDANN), 24-h average of SD of 5-min N-N intervals (SDNNIDX), and root mean square successive difference of N-N intervals in ms (rMSSD) (Umetani et al., 1998). Mean CR HRV values are indicated by filled diamonds and mean WD values by filled circles. See Table 2 legend for HRV definitions.