In the study of Williams PT et al. 1, the risk of arrhythmias was similar in walkers and runners who spent similar amounts of energy during exercise. There was no significant increase in the risk of arrhythmias associated with distance traveled, exercise intensity or marathon participation.
The risk of arrhythmia was lower by 4.4% for each metabolic unit, MET (one MET equals resting resting oxygen (about 3.5 ml * kg-1 * min-1). The risk of arrhythmia was lower by 14.2% when spending from 1.8 up to 3.6 MET / day, 26.5% lower with expenditure 3.6 to 5.4 MET / day and 31.7% lower with spending more than 5.7 MET / day.
The risk was estimated in relation to spending less than 1.8 MET / day.
Running and walking are relatively safe in causing arrhythmia in athletes.
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