What is "runner's high"? And what happens in our bodies to create it?

ST. PAUL, Minn. — Tens of thousands of runners might still be in recovery mode today after this weekend's Twin Cities Marathon.

That doesn't mean they're not basking in the bliss of finishing a long race. What is "runner's high"? And what happens in our bodies to create it? It's hard to match the feeling of winning a marathon, but that doesn't mean those still miles from the finish line aren't finding joy. "I started feeling it about maybe 23, 24 miles into marathon," said runner Jose Perales.

"It was just pure accomplishment and adrenaline that I pushed through to the end," described another runner. Happiness from running some would describe as a high. Chris Lundstrom, a senior lecturer at University of Minnesota and long distance running coach, has experienced the unique feeling many times.

He said "runner's high" is a subjective feeling. "People describe a sense of euphoria, a feeling of wellbeing after finishing running especially," said Lundstrom. Do runners need to reach a certain distance to feel the high? One told us she definitely doesn't notice the high in the first few miles, describing that opening stretch as tough.

"That probably has some variability to it, too," said Lundstrom. "I think as a general rule, it's gotta be 20-plus minutes (of running)." What is happening in the body that creates the high when running? "The original theory was it was endorphins which our body produces.

these and they go throughout our body," said Lundstrom. Endorphins can help a ru.