It is important to track your level of activity and try to increase it. This is not only because it will assist with weight loss but also because it is so good for you!
Some weight loss approaches do not give any credit for exercise, which I think is a mistake. The addition of regular exercise into your daily routine can definitely help with weight loss both directly (by burning additional energy) and indirectly by boosting your mood. The key here is to make exercise part of your daily routine. The once-in-a-while visit to the gym that leaves you feeling exhausted and deserving of a treat is definitely not helpful!