A calorie deficit is literally the only way to burn fat. Your body won’t touch its fat deposits if it’s getting enough energy from the food you eat. Working out has a limited effect on the amount of fat you burn. It’s all about how much you eat. If visible abs are what you’re after, that means dieting so that your body fat percentage gets low enough. The reason we lift while dieting is to preserve the muscle mass. By just dieting you’re going to lose both fat and muscle.