Maximum speed and distance traveled in response to saline (Days 1–2) and methamphetamine (Days 3–5) in the parental C57BL/6J (B6J) and C57BL/6NJ (B6NJ) substrains. (A) Sex-combined maximum speed (m/s) across training days. There was a significant increase in maximum speed in B6J versus B6NJ mice on Day(D) 3, D4 and D5 (*all p’sadjusted < 0.0001). (B) Maximum speed (m/s) across training days in females. There was a significant difference increase in maximum speed in B6J versus B6NJ females on D3 (*padjusted = 0.0005), D4 and D5 (*p’sadjusted < 0.0001). (C) Maximum speed across training days in males. There was a significant increase in maximum speed in B6J versus B6NJ males on D1 (padjusted = 0.03), D3, D4 and D5 (*p’sadjusted < 0.0001). (D) Sex-combined distance traveled (m) across training days. There was a significant increase in distance traveled in B6J versus B6NJ mice on D3, D4 and D5 (all p’sadjusted < 0.0001). (E) Distance traveled across training days in females. There was a significant increase in distance traveled in B6J versus B6NJ females on D3, D4 and D5 (*all p’sadjusted < 0.0001). (F) Distance traveled across training days in males. There was a significant increase in distance traveled in B6J versus B6NJ males on Day 3, Day 4 and Day 5 (*all p’sadjusted < 0.0001)