The influence of beta-blockade on cardiac output in a maximum exercise test

Fikenzer S1, Drechsler K4, Falz R1, Tegtbur U3, Thomas M2, Schulze A1, Bressau K1, Hoppe S1, Busse M1

1 Institute of Sports Medicine, University of Leipzig (Director: Prof. M. Busse, MD)
2 Orthopedic Clinic & Polyclinic, University of Leipzig  (Director: Prof. Dr. med. G. Von Salis-Soglio)
3 Center of Sports Medicine, Hannover Medical School (Leader: PD Dr med. U. Tegtbur)
4 Clinic of Cardiology, Heart-Center-Leipzig (Director: Prof. Dr. med. G. Schuler)

Summary

Fikenzer S, Drechsler K, Falz R, Tegtbur U, Thomas M, Schulze A, Bressau K, Hoppe St, Busse M. The influence of beta-blockade on cardiac output in a maximal anaerobic test. Clinical Sports Medicine International – Germany CSMI 4: 12-18

Objective: This study examines the changes in cardiac output (Q) during and after effort and assesses the extent to which β-blockade influences the development of cardiac output during effort. This was examined during and after a maximal anaerobic test.

Materials and methods: Five male students of the University of Leipzig (average age – 25.4 yrs, average BMI – 23.98 kg/m2, average RR – 141.2/80.8) with hypertension and pre-hypertension participated in a maximal anaerobic test. After four days’ rest, they began a three-day course of 5 mg/d of bisoprolol and, on the last day of this, they participated in a repeat test. We used the bioimpedance device Physio Flow™ to analyze Q. Variables were examined between 0% and 100% of maximum effort at 10% increments and in the rest periods after the first, third and fifth minutes.

Results:

• β-blockade does not influence Q during effort;
• β-blockade does not influence maximum effort;
• β-blockade does not influence maximum oxygen uptake.

Conclusion: It was possible to demonstrate that cardioselective β-blockers do not affect cardiac haemodynamics under maximum effort, or do they restrict cardiac performance regarding VO2max, VE and Watts.

Keywords: arterial hypertension, cardiac output, stroke volume, heart rate, exercise test, beta blocker, students