Metabolic energy correlates of heart rate variability spectral power associated with a 900-calorie challenge

We studied healthy males challenged with a 900 cal test beverage and correlated ee with the raw (ms2) and normalized units (nu) of total power (tp),low frequency/high frequency (lf/hf) and vlf spectral power of heart rate variability (hrv). the correlations were evaluated during 20 min of normal breathing (nb,control) and 20 min of paced breathing (pb) at 12 breaths ṡ min-1 (0.2 hz). ee was not significantly correlated with any of the hrv variables before the metabolic challenge. after the challenge,ee was positively correlated with lf/hf and with vlf; vlf was also positively correlated with lf/hf during both nb and pb. these findings suggest that ee may be a correlate of lf/hf and of vlf spectral power of hrv in healthy adolescent/young adult males. the association of lower resting energy expenditure with lower amounts of vlf spectral power may occur in individuals with predilections for obese phenotypes. © 2011 richard m. millis et al.