I've always been led to believe that it's fine to cross-train in that way. It's pretty rare I have a full day off. On my run rest days I weight train or do aerobics, pilates etc
I think it's just important to listen closely to your body and if you are fatigued be prepared to take an unscheduled day off all exercise to give your body a little respite.
Hope that helps x
try a different browser Tigerlily - the site seems fine to me.
all registered at 2.32am - fingers, toes and everything else crossed!
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