If you don't take a day off, your body can't repair and it will end up hindering your progress. Try one of Sparkpeoples pilate videos so that you are doing low intensity exercise-your body will thank you for it.
Interestingly, I read somewhere that Kenyans have extreme rest days, so important are they to training. On their rest days, they do NOTHING-napping mid day and moving as little as possible. www.guardian.co.uk/lifeandstyle/2011/feb/1
"For Kenyan runners, rest is a serious business. I spoke to some top British athletes who had come to Kenya to train, and I asked them what they thought the biggest difference was between the Kenyans' training and their own.
"Rest," they said, unanimously."