Effects of sustained training on left ventricular structure and function in top level rowers

Abstract

The effects of vigorous training on left ventricular structure and function were evaluated in 15 top level rowers using electrocardiography, Doppler echocardiography and radionuclide angiography. All subjects were studied after 1 month of deconditioning and again after 5 months of vigorous training. After training there was an increase in the ventricular hypertrophy voltage criteria proposed by Sokolow-Lyon and by Friedman but not in that proposed by Casale; T wave amplitude in leads V5 and V6 increased in nine subjects, was unchanged in one and decreased in five; the mean values were also unchanged. Training induced a significant increase in left ventricular end-diastolic and end-systolic diameter and in left ventricular mass index, while peak systolic stress and mean wall stress index decreased. No change was detected after training in the mean values of Doppler echocardiographic and radionuclide angiographic data; nevertheless a significant relationship was found between changes in T wave height in V5 or V6 and in peak filling rate, and between changes in T wave height and ejection fraction. Our study confirms that the effect of vigorous training on left ventricular mass and dimensions does not include changes in mean values of systolic and diastolic function. The relationship between change in T wave amplitude and in peak filling rate values suggests that some metabolic or neurohumoral derangement occurs in the subset of athletes with T wave flattening, that is responsible for the slight reduction in peak filling rate and ejection fraction.

Physiological rules for the heart, lungs and other pressure-based organs

“…For example, the mismatch between cardiac and aortic sizing suggests that athletes will suffer an increasing outflow obstruction morphologically similar to aortic stenosis during heavy exercise. This may explain why chamber dilatation (30), myocardial microfibrosis (31) and exercise-induced troponin elevation (32) occur in athletes' hearts. Furthermore heavy exercise is associated with a worse prognosis than mild or moderate exercise (33,34), probably due to backpressure effects from the relatively small aortic sizing.…”

The Heart of Trained Athletes

“…1,26,46,47 However, the application of ambulatory (Holter) ECG monitoring to trained athletes unexpectedly documented substantial ectopy with frequent premature beats and complex ventricular tachyarrhythmias (including couplets and bursts of nonsustained ventricular tachycardia) in many such individuals. 48,49 These findings suggest that a variety of arrhythmias are part of the athlete's heart spectrum ( Figure 5).…”

The Effect of High-Intensity Rowing and Combined Strength and Endurance Training on Left Ventricular Systolic Function and Morphology

“…Similarly, there is a lack of research investigating the time course of the changes in LV morphology in athletes, such as rowers, who are involved in concurrent strength and endurance training programs. Some studies have found an increase in LV diastolic cavity size and mass after 5 months of training [5], while our group has shown an increase in LV diastolic cavity dimension but not LV mass index after 10 weeks of combined rowing and strength training in rowers [14]. Therefore, the aim of this investigation was to assess LV performance prior to, immediately after, and at 2 time points (5 and 45 minutes) during recovery from a simulated 2000-m rowing race both prior to and following 10 weeks of combined strength and endurance training.…”