Effect of training on left ventricular structure and functioning of the normotensive and the hypertensive subject.

OBJECTIVE: To review the literature on the effects of training on left ventricular structure and functioning of the normotensive and the hypertensive subject. METHOD AND RESULTS: Meta-analytical techniques were applied to selected echocardiographic reports on the effects of exercise training on the heart of normotensive subjects. The combined analysis of studies revealed that the hearts of competitive athletes may differ from those of nonathletes. Long-distance runners develop predominantly eccentric left ventricular hypertrophy, strength athletes predominantly concentric hypertrophy and cyclists a mixed type of hypertrophy. Relative to their respective controls, left ventricular mass was larger by 64% (P < 0.01) in cyclists, 48% (P < 0.001) in runners and 25% (P < 0.05) in strength athletes. There were no differences in left ventricular systolic and diastolic function at rest. The meta-analyses of longitudinal studies in which athletes or nonathletes were assessed in active and inactive periods showed that physical training per se can affect cardiac structure. The few reports concerning hypertensive patients suggest that dynamic physical training seems to reduce rather than increase left ventricular mass, in which effect the reduction in blood pressure might play a part. CONCLUSION: Cross-sectional and longitudinal studies indicate that physical training may increase heart size in the normotensive subject. In contrast, heart size in the hypertensive patient may decrease in response to dynamic training.

Optimal definition of daytime and night-time blood pressure.

OBJECTIVE: To review and categorize methods to define daytime and night-time blood pressures and to propose an optimal definition. METHODS: The methods can be divided into clock-time-independent and clock-time-dependent methods and, in addition, into wide methods, which use all pressure measurements for the entire 24 h period, and narrow methods, which exclude some of the measurements. RESULTS: The asleep and awake blood pressures, mostly defined as the in-bed and out-of-bed blood pressures, can be considered the optimum standard. Wide (square-wave fitting) and narrow (cumulative-sum analysis) clock-time-independent methods perform well with most subjects, but are problematic with reverse dippers because they identify periods of high and low blood pressure in these subjects that do not coincide with the day and the night. The results from fixed-time methods deviate from the awake and asleep blood pressures whens the predefined times do not coincide with the times subjects go to bed and arise; this is less of a problem for the narrow methods, in which data from morning and evening transition periods are discarded, than it is for the rigid time schedules of the wide methods. Reproducibilities of the various methods are roughly similar. CONCLUSION: We suggest that the optimal definition of daytime and night-time blood pressure is provided by the narrow clock-time-dependent method, in which data from morning and evening transition periods are excluded, because it is simple, reasonably accurate and reproducible and can be applied without disruption of the living habits of most subjects.