My experience is definitely not extensive. As I stated before I am 62 and like to run/walk half marathons, that being said I occasionally have strains and pains which goes with the sport.
A few years ago, I had some stiffness in my low back that was almost constant. I did a 21 day WF and did a very calming yoga routine twice a day. I continued to work at my office job and take a quick nap in my car at lunch each day.
The low back pain went away and my flexibility greatly improved with the yoga.
I tore my hamstring and sacrotuberous ligament over a year ago and that is why I was doing the extended fast in 2/2015 when I had the potassium scare. I felt like the hamstring was really improving and would love to have continued another week or so.
That is why I am now doing another WF hoping to go deep into the healing.
Donna