Article

Measures of cardiac autonomic control in women with differing volumes of physical activity.

School of Life Sciences, Oxford Brookes University, Oxford, UK.
Journal of Sports Sciences (Impact Factor: 2.1). 06/2008; 26(7):781-6. DOI: 10.1080/02640410701836895
Source: PubMed

ABSTRACT In this study, we investigated heart rate variability in women who exercise regularly, but with differing volumes of physical activity. Forty women participated and were allocated to either a "high" or "moderate" activity group. Heart rate as R-R intervals was recorded during supine rest and analysed using time domain, frequency domain, and Poincaré plot techniques. All time domain and Poincaré analysis measures revealed significant differences in heart rate variability between the "high" and "moderate" activity groups. Frequency domain analysis also revealed a significant difference between the two groups in absolute measures of high-frequency and low-frequency power, but not between measures such as the low-frequency/high-frequency ratio, proposed to represent the sympathetic/parasympathetic balance of cardiac control. The results demonstrate that there is a significant difference in heart rate variability between women who engage in "high" compared with "moderate" volumes of physical activity, which may have implications for cardiac autonomic health.

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    • "Furthermore, the low frequency/high frequency ratio (LF/HF ratio) was calculated as a measure that might express sympathovagal balance. The R-R intervals were also used to produce Poincaré plot axes: the short diameter of ellipse (SD1) and the long diameter of ellipse (SD2) (Braun et al., 1998; Gilder & Ramsbottom, 2008; Mourot et al., 2004). Poincaré plot variables were normalized by dividing the absolute value by the mean R-R intervals and then multiplying by 1000 (SD1 nu, SD2 nu) (Tulppo, Makikallio, Seppanen, Laukkanen, & Huikuri, 1998). "
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    • "(Poincare´plots' descriptor: deviation of instantaneous beatto-beat R-R interval variability is the long diameter of ellipse) values (Braun et al., 1998; Mourot et al., 2004; Gilder & Ramsbottom 2008). Non-parametric (Fast Fourier transform) was used to obtain the frequency domain measures of HRV. "
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