Options:
(1) drink diet drinks; or
(2) drink your fizzy drinks at "optimal" times (PWO, AM, when glycogen depletion occurs)
(3) replace good carbs with these "poor" carbs.
Calories In v's Calories Out is main determinant of overall weight change, so therefore if for example you drank 1 litre of coke and ate no other carbs, you would probably be OK and not overfill glycogen stores. Reality is though that if your in calorie surplus/deficit, quality of carbs and food will matter as to whether changes in mass are loss/gain of muscle or fat, and further, if you drink 200g of coke carbs per day, its very unlikely that you will be full and not consume other carbs, not to mention risk be nutrient deficient and having gingivitis