Moderate altitude but not additional endurance training increases markers of oxidative stress in exhaled breath condensate - Heinicke, I; Boehler, A; Rechsteiner, T; Jelkmann, W; Hofer, M; Rawlings, P; Araneda, OF; Behn, C; Gassmann, M; Heinicke, K (Eur J Appl Physiol, 2009)