The Home Stretch

At the finale of a marathon (or half-marathon for that matter, as this one) the runners experience a spurt of energy that propels them over the finish line. In his case, some doping might have been involved. Weekly Prompts Weekend Challenge: Finale

It Didn’t Look Erratic

but the dictionary informs me that this is an erratic boulder. According to the plaque it is 30 million years old. And lo and behold! it checks out. FOWC with Fandango: Primordial