when to increase workouts

starzluv94

So I have added walking 40 min a day and rowing 20 min a day three times a week. I am wondering when I should start increasing the number of workouts. My plan is to add days and time of rowing and then add pilates when I get in better shape because right now there is no way I could get on the floor to do an entire workout. I just am not sure when and how to add exercise. I dont want to go too slow but I dont want to go to fast. Any help???