title: [Heart rhythm characteristics of boys undergoing physical loading].
mesh_terms: D000222:Adaptation, Physiological; D002648:Child; D004562:Electrocardiography; D006339:Heart Rate; D006801:Humans; D008297:Male; D010806:Physical Education and Training; D005082:Physical Exertion; D012420:Running; D013997:Time Factors
vernacular_title: Osobennosti serdchnogo ritma u mal'chikov pri fizicheskikh nagruzkakh.