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Abstract This study compared cardiovascular and metabolic responses during concentric and eccentric stepping. Eight participants (5 m, 3f; 22 ± 2 years) performed maximal concentric and eccentric ramp incremental tests on a modified stepping ergometer. Subsequently, three randomized 15‐min constant‐power tests were performed (1) concentric stepping at 90% of the concentric lactate threshold (LT), (2) eccentric stepping at the same power, and (3) eccentric stepping at the same oxygen uptake (V̇O2). At equivalent power (36 ± 6 W, p = 0.62), eccentric stepping resulted in 46 ± 8% lower V̇O2, 16 ± 6% lower heart rate (HR), and 11 ± 5% lower mean arterial blood pressure compared to concentric (p

Abstract Aims Heart failure with reduced ejection fraction (HFrEF) induces skeletal muscle mitochondrial abnormalities that contribute to exercise limitation; however, specific mitochondrial therapeutic targets remain poorly established. This study quantified the relationship and contribution of distinct mitochondrial respiratory states to prognostic whole‐body measures of exercise limitation in HFrEF. Methods and results Male patients with HFrEF (n = 22) were prospectively enrolled and underwent ramp‐incremental cycle ergometry cardiopulmonary exercise testing to determine exercise variables including peak pulmonary oxygen uptake (V̇O2peak), lactate threshold (V̇O2LT), the ventilatory equivalent for carbon dioxide (V̇E/V̇CO2LT), peak circulatory power (CircPpeak), and peak oxygen pulse. Pectoralis major was biopsied for assessment of in situ mitochondrial respiration. All mitochondrial states including complexes I, II, and IV and electron transport system (ETS) capacity correlated with V̇O2peak (r = 0.40–0.64; P

Abstract Background Menopause represents a turning point where vascular damage begins to outweigh reparative processes, leading to increased cardiovascular disease (CVD) risk. Exercise training reduces CVD risk in postmenopausal females via improvements in traditional risk factors and direct changes to the vasculature. We assessed the effect of moderate (MODERATE‐IT) versus heavy (HEAVY‐IT) intensity interval exercise training upon markers of cardiovascular health and vascular repair in postmenopausal females. Methods Twenty‐seven healthy postmenopausal females (56 ± 4 yr) were assigned to 12 weeks of either MODERATE‐IT or HEAVY‐IT, twice per week. MODERATE‐IT consisted of 10s work, and 10s active recovery repeated for 30 min. HEAVY‐IT comprised 30s work, and 30s active recovery repeated for 21 ± 2 min. Endothelial function (flow‐mediated dilation), arterial stiffness (pulse wave velocity), and V̇O2peak were assessed pre‐training and post‐training. Blood samples were obtained pre‐training and post‐training for enumeration of circulating angiogenic cells (CACs), culture of CACs, and lipoprotein profile. Results V̇O2peak increased 2.4 ± 2.8 ml/kg/min following HEAVY‐IT only (p 0.05). Peripheral pulse wave velocity reduced 8% with exercise training, irrespective of intensity (p 0.05). CAC adhesion to vascular smooth muscle cells (VSMC) increased 30 min post plating following MODERATE‐IT only (p