This increase in myostatin following mechanical unloading may have been expected given the fact that exercise training (i.e. loading) results in decreased skeletal muscle myostatin in healthy humans and in several pathological states [17], including HF [9] and insulin resistance [18], as well as in decreased skeletal and cardiac muscle myostatin expression in a rat model of HF [15]. The gene discussed is MSTN; the disease is hydrops fetalis.