Eating according to your blood type sounds really quackish to me, no offense. Why not just eat sensibly and eat less to lose weight instead of going on some sort of "magic" diet that restricts you to x, y, and z?
And I think the exercise recommendations are really nonsense. All humans benefit from vigorous cardiovascular exercise. No one blood type is more suited to having a healthy heart than another. Yoga is great for everyone, as well. Why shouldn't it be?
If I were you, I'd stay away from it. You can go on the Atkin's diet if you think that'd help you or you want to, but don't go on it just because your blood doesn't have antigen markers on it.