Re: What has been your biggest obstacle?
I think for most "normal" people the biggest obstacles are life in general. I mean if you, like me, have a family and a job where you may be working 50-60 hours per week. You probably don't have the time to be one of those 3 hour a day gym guys or gals where you can really make leaps and bounds.
That said, I have been a CFer for 5 years and I make great progress when I go 5 times a week, eat the right foods and get at least 6 hours of sleep. That's my goal but rarely achieve it. I don't beat myself up for that as work and family are going to win the priority contest.
I'm 48. I love Crossfit and hope I can do it til my last days.