Seven months ago, Courtney Parker was working out at Club Sierra, as she had done off and on for more than 15 years. She began swimming in the club's pool when she was 7 years old.On this day, however, David Williams, a longtime trainer and retired professional body builder, approached her."She had a lot of will, and I don't see that in many people," said Williams. "When I do, I grab it and take it as far as I can."He asked her to give him a month to see what he could do.For Parker, it did not take that long."It …