I would base exercise during induction on your individual goals. When I started I didn't exercise on induction and I still lost weight during the first two weeks-quite a bit actually I was surprised. As I started to slow down then I decided to start taking long walks (5 miles or so) three times a week. It really depends on you. A friend of mine was on induction and his body was so used to the carb intake that when it didn't get any and he went out walking at the start of induction he had a really difficult time (he said he felt like he was gonna die). I also know from past experience that when I exercise the first few days of a diet that it is a bit much to put my body through. I believe this is because my body was used to so many carbohydrates, and then to have a sudden decrease on the amount of food and calories I was putting in my body, and then to exercise without first letting my body adjust I would get extremely tired and dizzy and my blood sugar had to have been about 50 because my body was used to pumping out all that insulin.
To make a looooooooong story short. It is an individual decision, but I wouldn't recommend strenuous exercise for at least the first week of atkins, especially if your body is used to lots of carbs and calories.
Hope I could help.
Christine