Changes of ROS during a two-day ultra-marathon race - Hattori, N; Hayashi, T; Nakachi, K; Ichikawa, H; Goto, C; Tokudome, Y; Kuriki, K; Hoshino, H; Shibata, K; Yamada, N; Tokudome, M; Suzuki, S; Nagaya, T; Kobayashi, M; Tokudome, S (Int J Sports Med, 2009)