2old/chick/DD - I've been reading about boston and apparently the downhills trash your legs before the uphills. Is that right? Trying to do the 2 in 6 days means I'm trying to get a few more 20s than normal. Already done 2 This year. And I am doing regular squats and lunges to build the legs up which I never normally do. Fortunately I live at the top of the kennet valley so always have a long climb back home at the end of every run.