Now that’s muscle memory.

Scientists have found the earliest evidence of animal muscle on 565 million-year-old rocks bearing the marks of animal locomotion. On Canada’s east coast, 150 kilometres south of St. John's, the fossilized trails of soft-bodied creatures predate modern animals by 30 million years. It’s suspected that even these earliest bodybuilders at one point had posters of Arnold on their bedroom walls.

Source: CBC News