I've read that to lose weight effectively you have to manage your heart rate. I have just started using this heart rate monitor to be sure that I am keeping myself in the right zone. It has an alarm on it that can be set if I start to drop out of that zone, or go to high. It is relatively comfortable and goes just below my bra, after I start working out I barely realize it's even there. Well worth the money (I did use a coupon code and still got free shipping!) (Posted on 5/15/12)