Although several investigations have demonstrated that prolonged aerobic 
exercise results in decreased left ventricular (LV) function, few have examined 
the impact of an acute bout of high-intensity exercise on right ventricular (RV) 
and LV systolic and diastolic function. Cardiac magnetic resonance imaging with 
tagging was used to study the impact of high-intensity interval exercise on 
biventricular function in 9 endurance-trained (ET; Vo(2)max 69 +/- 7 ml/kg/min) 
and 9 normally active (NA; Vo(2)max 44 +/- 9 ml/kg/min) men. Subjects underwent 
baseline cardiac magnetic resonance imaging assessments (pre) and then performed 
an average of 14 1-minute intervals at 97 +/- 11% (NA) and 99 +/- 6% (ET) of 
peak power output, separated by 2 minutes of recovery at 21 +/- 6% (NA) and 21 
+/- 9% (ET) of peak power output. After exercise, 2 cardiac magnetic resonance 
imaging assessments (post 1 at 6.2 +/- 2.6 minutes and post 2 at 38.4 +/- 3.8 
minutes) were completed. RV and LV ejection fractions, twist, basal and apical 
rotation rates, rate of untwisting, circumferential strain, and timings were 
examined. No significant change in RV and LV ejection fractions, twist, 
untwisting rate, or strain after exercise occurred in the NA group. In the ET 
group, RV ejection fraction (pre 56 +/- 4%, post 1 54 +/- 4%, post 2 54 +/- 3%) 
and LV ejection fraction (pre 62 +/- 4%, post 1 59 +/- 4%, post 2 58 +/- 4%) 
were decreased at post 1 and post 2, while untwisting rate, apical rotation 
rate, and circumferential strain were decreased at post 2 (all p values <0.05). 
In conclusion, biventricular systolic and diastolic dysfunction occurred after 
14 minutes of high-intensity exercise in ET athletes, a phenomenon not observed 
in NA subjects.