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Updated: Aug 14, 2026

Implantation of Combined Telemetric ECG and Blood Pressure Transmitters to Determine Spontaneous Baroreflex Sensitivity in Conscious Mice
Published on: February 14, 2021
Aerobatic flight effects on baroreflex sensitivity and sympathovagal balance in experienced pilots
Jean-Claude Jouanin1, Caroline Dussault, Denis Tran
1Dept. of Integrative Physiology, IMASSA, BP 73, F-91223 Bretigny-sur-Orge Cedex, France. jcjouanin@imassa.fr
Background:
Aerobatic flights subject pilots to accelerations and, therefore, to heavy physical workloads.
Objective:
Our aim was to document changes in spontaneous baroreflex sensitivity and disturbances of sympathovagal balance after exposure to "push-pull" accelerations.
Methods:
During 30-min flights, five aerobatic pilots performed five series of descending spirals: first, 30 s under negative (-3 Gz max), and then 30 s under positive (+4 Gz max) G loading, climbing between each series to regain altitude. A stand-test was performed before (T0), immediately postflight (PF), 1 h (PF1), and 2 h after (PF2) the flight. A Finapres apparatus recorded heart rate (HR) and BP during the stand-tests.
Results:
Resting HR was higher at PF than T0 in supine (11.2 +/- 5.3%, p < 0.01) and standing (11.0 +/- 4.9%; p < 0.05) positions. Sequence analysis of spontaneous baroflex sensitivity (BRS) and spectral analysis of HR variability showed that: a) supine spontaneous BRS did not differ between preflight and postflight, while parasympathetic modulation of HR variability tended to increase; and b) supine spontaneous BRS was higher at PF1 than PF (PF: 0.011 +/- 0.0014 ms x mmHg(-1), PF1: 0.015 +/- 0.0012 ms x mmHg(-1); p < 0.05) and parasympathetic modulation of HR variability (high frequency component) was higher at PF2 than PF (PF: 0.014 +/- 0.007, PF2: 0.039 +/- 0.009; p < 0.001).
Conclusions:
These findings may reflect a change in the sympathovagal balance during the second hour of recovery from repeated push-pull maneuvers.
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