A heavier fitness routine means you need calories — and carbohydrates — more than ever. (iStockPhoto)

It’s a common tale. You want to lose weight and get fit, so you decide to work out more and cut calories, in particular all those starches — breads, rice, pasta and cereal — that we keep hearing are making us fat.

Except it doesn’t work. What gives?

Weight loss doesn’t always come down to calories in vs. calories out, especially when you are trying to find the balance between aerobic exercise and eating carbohydrates. It is essential to find the right mix for you.

You need carbohydrates to survive

There is so much negative information around sugar that often carbohydrates get mixed in, because technically sugar is a carbohydrate. It is essential to understand the difference. We do not need processed sugar, but the body absolutely needs carbohydrates for survival and a healthy metabolism. Especially if you are exercising, carbohydrates are needed — they are the fuel to assist our metabolism, feed our brain and manage our stress hormones.

So where do we find carbohydrates?

●Non-starchy vegetables.

●Fruit.

● Starches. This category includes bread, pasta, rice, corn, potatoes, peas, cereals, crackers and quinoa. Starches can be categorized as unprocessed, meaning they are whole and intact grains, or processed/refined, meaning they have a higher sugar content and less fiber, protein and fat after being stripped of nutrients during processing.

● Sweets, candy, refined sugar: Much of our carbohydrates are found in sweets and hidden sugars. Sugar is in a lot of condiments, packaged foods and beverages.

Finding a balance

It is very common to increase your exercise and decrease your calories and not see results. Why is this? It comes down to stress. When you create such a caloric deficit by eating less and exercising more, you may be putting your body into a stressed state. If the body thinks it is in trouble, it will lower its metabolic rate and hold on to weight. While it seems logical to eat less and exercise more to achieve results, often one has to eat more to fuel workouts.

Tip: Try slowly adding a serving of starch, balanced with protein and fat, within an hour after aerobic exercise. (Some options: a half-cup of oatmeal with cinnamon, a one-ounce slice of toast with 1 to 2 tablespoons of nut butter, or a half-cup of rice with 1 to 2 cups of vegetables and 3 to 5 ounces of protein.) Add a serving a day and monitor your hunger, energy and weight for a week to see whether another serving is needed. Take it slowly to prevent overeating and see how the body reacts. Everyone has his or her own ideal ratio of carbohydrates to exercise. Find the ratio specific for you.

The United States government once considered butter and margarine as one of seven food groups to consume daily. Look back at other advice that, sadly, is no longer a part of the USDA's dietary guidelines. (Jayne W. Orenstein/The Washington Post)

You might follow your new restrictive plan diligently, but as the day goes on, hunger and cravings take over and you overeat. This also goes back to stress. The body thinks it’s in trouble, so when food is finally served at dinner, it says, “This may be the last time I eat, so I’m going to take in all I can!” Not only that, it stores most of it as fat. You are holding on to your weight because dinners and late-night snacks are so large that your total calorie intake probably did not decrease, despite your efforts earlier in the day.

Tip: Spread calories out throughout the day and consider adding one to two servings of starch or fruit to your daily diet and notice how that affects evening hunger and weight.

Another common pitfall when decreasing starch intake is eating a lot of fruit throughout the day as a replacement. Because fruit is healthy and full of nutrients and fiber, we often think it is can be eaten in unlimited quantities, like vegetables. Fruit does contain a good amount of calories, and that needs to be taken into account.

Tip: One to two servings of unprocessed starch (for instance, oatmeal at breakfast or quinoa at lunch) may provide satiation instead of three to five pieces of fruit. Monitor servings of fruit and eat some starch and see how the body reacts.

Take a day or two to understand how your carbohydrate intake and workouts are fitting in with your goals. Keep a food log so you can get an idea of how many servings of carbohydrates you eat a day and how they are timed in your day. And notice whether a tweak in timing, portions or carbohydrate choice could support you in reaching your goals.

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Berman is a registered dietitian, a personal trainer and owner of Jae Berman Nutrition.