Important: I'm not a doctor, have no medical or sports training or expertise and the information in this post has been mainly been gleaned from the internet. DO NOT follow any advice in this post blindly. You should seek medical advice or the advice of a sports specialist yourself.
One of the main reasons I have started doing indoor rowing is to lose weight. Ignoring fads, crash diets, etc. I'm adhering to the core concept that to lose weight you need to expend more calories than you consume each day. This can be done be eating differently, exercising or doing both. This isn't rocket science. If you don't change what you eat but you start exercising you'll expend more calories than you did before and either lose weight or, if you are still consuming more calories than you are expending, at least slow down your weight gain. Similarly, if you eat less or change your diet then you will either lose weight or at least slow down any weight gain.
On the eating side I'm trying to eat smaller portions, eat better foods (fewer processed and more fruit and veg) and cut down on snacking. I'm kind of keeping a food diary and doing some calorie counting too but this isn't the focus of this blog post. Instead I want to focus on exercise and, more specifically, effective exercise.