That is basically what we are supposed to do. Exercise is very hard to do when there is no gravity. This will lower the weight on the ship. We will also bring some other food up that we can grow up in our green house. That is how we will plan to survive the life up on mars.
Water is one of the many problems on mars to.
There is not enough water on mars too. There is an ice cap but the water will have to be defrosted and purified before we can drink it. We will also use th waste to purify it once then purify it twice with the plants that we have. That is how we will solve that problem. The problem with temperature is that it is way to cold there.