Bryan Johnson· Author
as you get older for men yeah this gets bigger yeah this should stay the same I think it's the same ratio as my 17 year old on this one I think I'm gonna win is he here you know what we should get him in here we should really this is really all about beating challenge as you get older this number is going to be wider right because you lose sensitivity so a young person this should be small and that's what we're trying to get for Brian