Weight status, heart rate variability and habitual physical activity in British Primary School children

Abstract

The purpose of this study was to examine the relationships between habitual physical activity (PA), weight status and heart rate variability (HRV) in British Primary School children. A total study population of 197 children (46% boys, 54% girls, mean age 9±1.4, 87% Caucasian, 11% Asian, 2% African-Caribbean) were recruited from a Coventry, UK primary school. Height and weight was measured to calculate BMI. Children were categorised in weight status (normal weight, and overweight/obese) using internationally accepted cut-off points. Heart rate variability was measured in the supine position for a 10 minute period, with the final 3 minute sample used for analysis in the time and frequency domain using Kubios HRV Pro (Kubios, Finland). Yamax Digiwalker SW800 (Yamax, Japan) pedometers were the chosen method of measuring habitual physical activity over a four day period (2 weekdays, 2 weekend days). Results from the study revealed a significant correlation between average step count and mean RR (p=0.016 r=0.218) and LF (p=0.047 r= .180) although no other significant correlations were observed (p>0.05). No significant weight status differences were found for HRV indices in the time and frequency domain (p>0.05), nor was weight status significantly correlated with average step count (p=.959). ANCOVAs revealed significant age differences for mean RR (p=.014), SDRR (p=.05), RMSSD (p=.022), but not for HRV indices in the frequency domain. In conclusion habitual physical in terms of average step count is a predictor of mean RR and LF in children independent of age. HRV indices are not influenced by weight status, and average step count does not influence weight status.

Date of Award	2012
Original language	English
Awarding Institution	Coventry University
Supervisor	Michael Duncan (Supervisor) & Samantha Birch (Supervisor)