Many people turn to exercise and diet control in an effort to lose weight (Disclaimer: I am not one of those people). I was reading how sugar water equates to weight gain, which links to a on the subject.
Early research shows that your body does not feel full after consuming liquid calories, such as those in sodas, energy drinks, coffee, or juice. So, if somebody is trying to lose weight, then they should limit these types of beverages. The original article in the LA Times talks about the laws limiting the sales of soda in grammar schools, and argues that sports drinks should also be limited.
If your main focus on living a healthy lifestyle is to lose weight, then you probably do want to limit the beverages that you consume, other than water. Soda should already be limited, and it may not be a bad idea to limit sports drinks. However, while you are actually exercising and immiediately thereafter, I do not think that it makes sense to forgo the sports drink if that is what you are used to, especially if you will not be able to consume some solid calories immiediately thereafter.