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Updated: Jul 10, 2026
Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
[Limits of cardiac functional adaptation in "top level" resistance athletes]
1CNR Palazzo LITA Via Fratelli Cervi, 93 20090 Segrate, MI. caru@itba.mi.cnr.it
Background:
Sports activity, particularly when performed at high level, provokes cardiovascular adjustments depending on the type of sport and on the level of the load.
Methods:
We evaluated 15 athletes from the Italian national team during a non-agonistic period of cross country skiing, with non-invasive tests including exercise test, color Doppler echocardiography, Holter monitoring, physical examination and standard rest electrocardiogram.
Results:
Physical examination, rest electrocardiogram, exercise testing and echocardiography were all within the range of the expected values for this type of subjects. Holter monitoring recorded during the periods of agonistic activity revealed significant hypokinetic arrhythmias such as severe bradycardia, pauses, I and II degree atrioventricular blocks, and complete atrioventricular block in 2 cases; these features were not observed on Holter monitoring recorded during the non-agonistic period.
Conclusions:
The perfect health status of subjects and their racing results may bring about physiological functional adjustments, but these observations suggest the need for a follow-up to evaluate possible pathologic outcomes.
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