1. Relationship between heart rate variability and the serum testosterone-to-cortisol ratio during military service
- Author
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Jukka Huovinen, Heikki Kyröläinen, Mikko P. Tulppo, Juuso Nissilä, Keijo Häkkinen, and Vesa Linnamo
- Subjects
medicine.medical_specialty ,Supine position ,Physical Therapy, Sports Therapy and Rehabilitation ,General Medicine ,Autonomic nervous system ,Basal (phylogenetics) ,Endocrinology ,Internal medicine ,Heart rate ,medicine ,Heart rate variability ,Orthopedics and Sports Medicine ,Psychology ,Testosterone ,Morning ,Hormone - Abstract
The autonomic nervous system and circulating hormones control a stress reaction through a complex interaction. We tested the hypothesis that changes in cardiac vagal regulation may be positively associated with the serum testosterone-to-cortisol ratio during the first week of military service in 24 conscripts aged 19.0±0.3 years. Cardiac autonomic function was assessed by measuring high-frequency (HF: 0.15–0.4 Hz) and low-frequency (LF: 0.04–0.15 Hz) power spectral indices of R-R intervals during supine rest and during a controlled standing condition (5 min for both) from the second to the seventh mornings at the beginning of military service. Blood samples were collected to analyse the basal serum testosterone-to-cortisol ratio on the seventh morning. Changes in heart rate and high-frequency power measured in the standing condition were positively correlated with the serum testosterone-to-cortisol ratio at day 7 (r= − 0.42 and r=0.45, respectively; P
- Published
- 2009