Behaviour of running (14-day and 28-day) and control mice during a 20-min open field test. In (A), (B) and (C), locomotor activity (distance moved), exploration (rearing) and anxiety-related behaviour (% centre time) are represented respectively. *p < 0.05, ***p < 0.001 vs. corresponding control. N = 14–16 per group. Data represent means ± S.E.M.