Rob -- I tweaked my right upper quad the day before China Grove. It was fine until the finishing kick, made itself known, but didn't feel like I did any damage. It's been faintly tight since. Then it went completely OFF during some innocuous striders last TUE. Felt like a pulled muscle, not that I have much experience with that. Anyway, I've been resting it since -- I do not want any physical issues dogging me during late summer and fall marathon training.
Richard -- I use THIS AGE-GRADING CALCULATOR, which uses the most recent WAVA tables/factors. THIS ONE is nice, too.
“Everything you need is already inside.” -- Bill Bowerman