Heart Rate Variability Characteristics in Sedentary Postmenopausal Women Following Six Months of Exercise Training: The DREW Study Article

Full Text via DOI: 10.1371/journal.pone.0002288 PMID: 18523583 Web of Science: 000262614300007
Open Access

Cited authors

  • Earnest, Conrad P.; Lavie, Carl J.; Blair, Steven N.; Church, Timothy S.


  • Background: Decreased heart rate variability (HRV) is associated with a higher risk of mortality. Overall, postmenopausal women have lower levels of HRV than premenopausal women, which may be additionally complicated by lifestyle related behaviors such as physical inactivity and obesity. Though cardiorespiratory exercise training increases HRV, little is known regarding the exercise dose necessary to promote this improvement.; Methodology/ Principal Findings: Our primary aim was to measure HRV in post-menopausal women following 6-months of exercise training. We examined supine resting HRV in 373 post-menopausal women (45-75 y) after 6-months of randomly assigned and double-blinded administered exercise training exercise training at 50%, 100% and 150% of the NIH Consensus Development Panel's recommended minimal physical activity level. This corresponded to 4, 8, or 12 kcal/kg per week (KKW) of energy expenditure. At baseline, we observed no significant differences in HRV or hormone replacement use between treatment groups. However, we did observe that Caucasian women and those taking antidepressant medications had lower levels of baseline HRV. After 6-months of exercise intervention, we observed a dose dependent increase in all parasympathetically derived time and frequency domain measurements across exercise groups after adjustment for age, ethnicity, antidepressants, and baseline rMSSD (all, P < 0.001). For example, the parasympathetic index rMSSD was greater than control (23.19 +/- 1.0) for the 4-KKW (25.98 +/- 0.8; P=0.14), 8-KKW (27.66 +/- 1.0; P < 0.05), and 12-KKW (27.40 +/- 0.0; P < 0.05) groups at follow-up.; Conclusions/Significance: Moderate intensity exercise training exercise is sufficient to improve HRV in previously sedentary postmenopausal women in a dose-dependent manner, as 4-KKW is insufficient to improve parasympathetic indices of HRV, while 12-KKW conferred no greater improvement than 8-KKW.

Publication date

  • 2008

Published in

International Standard Serial Number (ISSN)

  • 1932-6203


  • 3


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