apple bmr calories cellular diet eatinghealthy fasting fruit hgh hunger insulin intermittent juice maintenance meals rainbow repair routine sauce weightloss yazio accountability beginning business challenge children consistency course emotions excel expectations goals goalsetting googlesheets growth habits health journey learn learning limitations miband motivation music planning precisionnutrition progress starter status stepbystep stress struggle support thresholds tracking women xiaomi barefoot coachgreg equipment exercises fitness injury intensity muscles overload recovery rest rpe shoes steps training workout sleep