"Wasn't sure if I could. But then I did. And now I'm suspiciously emotional about it," she wrote in the caption of the video.

That's why we chatted with Rachel MacPherson, CPT, a certified personal trainer and strength and conditioning specialist, who shares five essential core moves designed to strengthen and tone your core ...

Generally speaking, runners find their lactate threshold pace to be about a seven or eight out of 10 effort on a rate of ...