Moderate recovery unnecessary to sustain high stroke volume during interval training. A brief report

It has been suggested that the time spent at a high stroke volume (sv) is important for improving maximal cardiac function. the aim of this study was to examine the effect of recovery intensity on cardiovascular parameters during a typical high-intensity interval training (hiit) session in fourteen well-trained cyclists. oxygen consumption (vo2),heart rate (hr),sv,cardiac output (qc),and oxygenation of vastus lateralis (tsi) were measured during a hiit (3×3-min work period,2 min of recovery) session on two occasions. vo2,hr and qc were largely higher during moderate-intensity (60%) compared with low-intensity (30%) (vo2,effect size; es = +2.6; hr,es = +2.8; qc,es = +2.2) and passive (hr,es = +2.2; qc,es = +1.7) recovery. by contrast,there was no clear difference in sv between the three recovery conditions,with the sv during the two active recovery periods not being substantially different than during exercise (60%,es = -0.1; 30%,es = -0.2). to conclude,moderateintensity recovery may not be required to maintain a high sv during hiit. © journal of sports science and medicine.