Non-invasive determination of stroke volume and cardiac output after high intensity playing exercise in elite female soccer players.

BACKGROUND: Stroke volume (SV) and heart rate (HR), determining cardiac output (CO), are crucial hemodynamic parameters determining training adoptions to endurance training. In soccer, aerobic power as well as intermittent exercise performance varies significantly among level of competition as well as playing position. In this study cohort study we thought to determine the hemodynamic changes following a standardized soccer-specific exercise in female soccer players at the soccer field using a portable non-invasive hemodynamic monitoring tool.

METHODS: A non-invasive, portable continuous wave (CW) Doppler-based ultrasound system (USCOM, Sydney, Australia) was used to assess HR, SV, CO, and cardiac index (CI) using a suprasternal approach after a soccer specific exercise (5-vs-2-gameplay over 5 min) in an elite female soccer team of the German Fussball Bundesliga (15 females, 22.3+/-3.6 years).

RESULTS: 30 s after the peak exercise the mean HR increased significantly (121+/-26 /min vs 56+/-11 /min, p<0.05), while SV did not change significantly (75+/-25 ml vs. 80+/-13 ml, n.s.). CO increased significantly (9.2+/-4.1 l/min vs. 4.5+/-1.1 l/min) as did CI (5.3+/-2.1 l/min/m(2) vs. 2.6+/-0.6 l/min/m(2), p<0.05).

CONCLUSION: Elite female soccer players increase cardiac output after 5-vs-2-gameplay on average to 10 l/min, in single cases up to 18 l/min 30 s after peak exercise. Therefore significant peak hemodynamic demands are encountered in soccer game play. The increase of cardiac output is by far more achieved by an increase of the heart rate than by stroke volume changes in most of the female soccer players. On field hemodynamic exercise testing is feasible using the USCOM in elite soccer.