Everyone’s body is different but if you have already been sleeping on an all-foam mattress PerformaSleep believe you will adjust immediately and begin to notice a difference immediately. If you have been sleeping on any type of spring mattress it might take your body a little more time to adjust and this is why PerformaSleep ask that you sleep on the mattress for a minimum of 30 days to allow for this process to happen. Some people’s bodies are just a little more stubborn than others.