SPORTS-SPECIFIC ADAPTATION OF LEFT-VENTRICULAR MUSCLE MASS IN ATHLETES HEART .1. AN ECHOCARDIOGRAPHIC STUDY WITH COMBINED ISOMETRIC AND DYNAMIC EXERCISE-TRAINED ATHLETES (MALE AND FEMALE ROWERS)

The differentiation of the physiological left ventricular (LV) hypertr ophy of the athlete's heart in opposition to a pathological finding ma y be problematic especially in both strength and endurance trained ath letes with simultaneously large body dimensions: 64 male and 71 female rowers of regional up to national level were examined by (Doppler) ec hocardiography. In addition, the rowers were compared by matched-pair procedures both with 32 mate and 30 female non-endurance trained (pair wise similar body surface area) and with 28 male endurance athletes (p airwise similar absolute heart; volume). The so-called critical heart weight of 500 g was exceeded by 63 % of the male and 11 % of the femal e towers. 9 % of the male rowers showed even an LV muscle mass above t he limit of 3.5 g . kg(-1) body mass. The individual maximal body surf ace area-related values were 170 g . m(-2) (men) and 133 g . m(-2) (wo men). The LV enddiastolic internal diameter was measured to be above t he upper clinical limit of 55 mm in 69 % or 23 % of the male and femal e rowers, although a maximal LV wall thickness of 14 or 13 mm, respect ively, was never exceeded. The systolic LV function as well as ECG and blood pressure did not reveal any pathological findings, the diastoli c LV function was measured within the (supra) normal range. The LV wal l thicknesses, internal diameter and hypertrophic index (relation betw een wall thickness and internal diameter) were significantly higher in rowers than in non-endurance trained subjects, but similar if compare d to the endurance athletes. The clinical limits, however, keep their validity until a body mass of about 70 kg. In conclusion, some upper a bsolute clinical limits, especially those referring to Volume measurem ents, so far considered critical (LV internal diameter, heart weight a nd LV mass), may be clearly exceeded by healthy strength endurance tra ined athletes presenting high body dimensions. The LV wall thickness, however, rather exceptionally exceeded the clinical limits. If referri ng to body dimensions, the cardiac dimensions in towers are still lowe r in comparison to highly-trained ''pure'' endurance athletes. A speci fic influence of the isometric exercise component on the LV hypertroph y cannot be observed.