Cardiovascular responses to static exercise in boys: insights from tissue Doppler imaging

摘要: Ventricular functional changes and mechanisms of the cardiovascular responses during static exercise have not been well delineated in children. In this study, Doppler echocardiographic techniques were utilized to assess adaptations bilateral isometric leg extension at 30% maximal voluntary contraction for three minutes a group 14 healthy boys (mean age 10.2 ± 1.5 years). Mean heart rate rose from 77 9 106 11 bpm, stroke volume fell 59 52 7 ml, cardiac output increased 4.58 0.58 5.62 0.81 l min-1 (P < 0.05). arterial pressure 86 109 mm Hg, with no significant change peripheral vascular resistance. By tissue imaging markers, inotropic function improved by 59%, while lusitropic 38%. These findings suggest that (1) are similar those adult men, (2) triggers modest increases both systolic diastolic function.