Myoglobin deficiency impairs maximal oxygen uptake and exercise performance: a lesson from Mb mice.

Myoglobin (Mb) plays an important role at rest and during exercise as a reservoir of oxygen and has been suggested to regulate NO bioavailability under hypoxic/acidic conditions. However, its ultimate role during exercise is still a subject of debate. We aimed to study the effect of Mb deficiency on maximal oxygen uptake ( ) and exercise performance in myoglobin knockout mice (Mb ) when compared to control mice (Mb ).

Exercise Training Decreases Nitrite Concentration in the Heart and Locomotory Muscles of Rats Without Changing the Muscle Nitrate Content.

Background: Skeletal muscles are postulated to be a potent regulator of systemic nitric oxide homeostasis. In this study, we aimed to evaluate the impact of physical training on the heart and skeletal muscle nitric oxide bioavailability (judged on the basis of intramuscular nitrite and nitrate) in rats.

Methods And Results: Rats were trained on a treadmill for 8 weeks, performing mainly endurance running sessions with some sprinting runs.

Body mass and V'O at rest affect gross efficiency during moderate-intensity cycling in untrained young healthy men: correlations with V'O.

Seventeen young healthy physically active males (age 23 ±3 years; body mass (BM) 72.5 ±7.9 kg; height 178 ±4 cm, (mean ±SD)), not specifically trained in cycling, participated in this study.

Training-induced impairment of endothelial function in track and field female athletes.

Professional athletes are often exposed to high training loads that may lead to overfatigue, overreaching and overtraining that might have a detrimental effects on vascular health. We determined the effects of high training stress on endothelial function assessed by the flow-mediated dilation (FMD) and markers of glycocalyx shedding. Vascular examination as well as broad biochemical, hormonal and cardiometabolic evaluation of sprint and middle-distance female runners were performed after 2 months of preparatory training period and compared to age-matched control group of women.

Age-related decrease in serum dihydrotestosterone concentration is accompanied by impaired vascular status.

Introduction: The effect of androgens on the cardiovascular system in humans is ambiguous. Moreover, still little is known about the effects of the most potent androgen, dihydrotestosterone, on arterial stiffness and endothelial function. The aim of this study was to evaluate whether age-dependent alterations in serum concentration of dihydrotestosterone and its circulating metabolite are accompanied by changes in endothelial function and arterial stiffness.