Energy balance

Sustained moderate-intensity exercise (approx. 2000 kcal/week) prevents weight gain in young overweight women but produces significant fat loss in young overweight men, independent of dietary changes.

If you are a young overweight man, doing ~45 minutes of moderate exercise (where you can talk but not sing) 5 days a week will likely help you lose fat, even if you don't change your diet. If you are a young overweight woman, the same routine will likely stop you from gaining weight, which is a significant health benefit compared to doing nothing, even if the scale doesn't drop.