The post has 6.7 million views, and social media users across platforms accepted the challenge. Many performed the test solo or in groups, at the office, or as a family or couple. #biologicalage feed ...

I'm sat in my living room and my legs are pulsating, my heart rate is pumping and the room is a little less steady than it was 10 minutes ago. It’s not that I’m feeling the ‘gains’ of an intense ...