+1 to what Eden says.

It is crucial that you allow your body to recover. I always have 1 day off a week; rest week - sometimes 2. My training is in 4 week cycles, 1-3 being progressively harder, 4th week is recovery week where I still do workouts but with decreased volume and intensity. Physically, it helps to avoid injury and allows me to recover and mentally it makes me very, very happy!

I am on a rest week now..can you tell? happy, happy, happy....