Effects of Iron on Exercise Capacity During Hypoxia

实验性的：Intravenous iron sucrose

Infusion of 200 mg iron sucrose (Venofer) in 100 ml normal (0.9%) saline.

药品：Iron sucrose.

Volunteers will receive an intravenous infusion of 200 mg iron sucrose, before exposure to 8 hours of alveolar hypoxia. At the end of the exposure, pulmonary artery systolic pressure will be measured and volunteers will undertake an exercise test while breathing hypoxic gas.

其他名称：

• Iron sucrose = Venofer

安慰剂比较：Intravenous normal saline

Infusion of 100 ml normal (0.9%) saline.

药品：Normal saline

Volunteers will receive an intravenous infusion of 100 ml normal saline, before exposure to 8 hours of alveolar hypoxia. At the end of the exposure, pulmonary artery systolic pressure will be measured and volunteers will undertake an exercise test while breathing hypoxic gas.

Maximal exercise capacity during hypoxia, assessed by maximal oxygen consumption.

Volunteers will receive either intravenous iron or saline placebo, before exposure to 8 hours of alveolar hypoxia. They will then undergo an exercise test while breathing an hypoxic gas mixture. The primary outcome measure will be exercise capacity as determined by maximal oxygen consumption during this test. Volunteers will receive both interventions, via a crossover design. Due to uncertainty about the duration of action of iron at a cellular level, all volunteers will receive saline infusion on the first study day, and iron sucrose infusion on a second study day, at least one week later.

Maximal exercise capacity, assessed by peak power output.

Pulmonary artery systolic pressure.

Blood levels of oxygen-regulated proteins.