Heart rate variability, blood pressure variability, and baroreflex sensitivity in overtrained athletes.
OBJECTIVE
To assess the effects of abruptly intensified physical training on cardiovascular control.


METHODS
Retrospective longitudinal study.


METHODS
Research laboratory.


METHODS
Ten healthy athletes (5 men and 5 women) from track and field as well as triathlon.


METHODS
A 2-week training camp, including daily stepwise increasing cycling tests, running of 40 minutes, and additional cycling of 60 minutes.


METHODS
Time and frequency domain parameters of resting heart rate and blood pressure variability (HRV and BPV) and baroreflex sensitivity (BRS), before, during, and after the training camp.


RESULTS
We found significantly reduced HRV during the training camp (mean beat-to-beat interval: 1042 [937 to 1194] ms vs. 933 [832 to 1103] ms vs. 1055 [947 to 1183] ms, P < 0.01; root-mean-square of beat-to-beat interval differences: 68 [52 to 95] ms vs. 52 [38 to 71] ms vs. 61 [48 to 78] ms, P < 0.05). Further, BRS was significantly reduced: 25.2 (20.4 to 40.4) ms/mmHg vs. 17.0 (12.9 to 25.7) ms/mmHg vs. 25.7 (18.8 to 29.1) ms/mmHg, P < 0.05. These effects disappeared at a large degree after 3 to 4 days of recovery.


CONCLUSIONS
Abruptly intensified physical training results in an altered autonomic cardiovascular activity towards parasympathetic inhibition and sympathetic activation that can be monitored by means of HRV and BRS analyses and might provide useful markers to avoid the overtraining syndrome.
Baumert
Mathias
M
Department of Medical Engineering, University of Applied Sciences Jena, Germany. mbaumert@eleceng.adelaide.edu.au
Brechtel
Lars
L
Lock
Jürgen
J
Hermsdorf
Mario
M
Wolff
Roland
R
Baier
Vico
V
Voss
Andreas
A
D000328:Adult; D001265:Athletic Injuries / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D001794:Blood Pressure / Q000502:physiology*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006306:Health Surveys; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010806:Physical Education and Training; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D014142:Track and Field / Q000193:education*