If you've made the resolution to snuff out smoking this year, then one of your best allies in the fight can be exercise. It's great if you're already committed to a workout plan - after you quit, you'll see even better results because smoking and exercise have opposite effects on the body. While smoking hampers the inner workings of the heart and lungs by increasing blood pressure, phlegm buildup and heart attack risk, exercise reduces these risks. Within just one day of quitting, the benefits are apparent: blood pressure normalizes, heart attack risk declines and carbon monoxide levels in the blood decrease.