it's a hick ki. yes a kickey just like -- hickey just like teenagers give each other on the necks when tlair dating. -- they're dating. decorated olympian michael phelps made a splash on social media and it wasn't for winning another medal it was for a circumstance kl -- circle of a different kind. >> those are cup marks guys. i got cupped the other day. >> the swimmer has praised the techniques and many other athletes have caught on too. today i learned how it works. >> going for the areas of tension. >> stacey is working on jackie miller a try athlete. these cups -- triathlete these cups increase blood flow and it relaxes the muscles. the cups are left there from two to 15 minutes. if there's a lot of toxins in the muscles dark hickeys could they can remain for days. >> does that hurt at all? >> miller has been doing this for years and swears by it. >> she's kept me injury free. there's weeks i train upwards of 25 hours hour a week and i've never had a serious injury. >> cupping is the newest techn