When creating your fitness null GetFit will take into account your:

Personal details and fitness level - height, weight, sex and fitness history
Fitness goals - you many want to lose weight, improve flexilibility, reduce stress, build muscle or train for specific sports.
Schedule - how much time do you typically have to train? GetFit will factor this into the null it creates for you
Equipment access - GetFit will create your null using the equipment you have access to. If you have no equipment GetFit will build your null using non-equipment based exercises.