In the fitness community, carbs are vilified in one discussion, praised in another, worshipped on food blogs, and damned all the while. Of course, so many strong and contradictory opinions can’t all be completely right, but they each have some merit, even when it comes to reaching your fitness goals. So what are carbs? And what’s the best approach to fitting them into your diet (while still fitting into your favorite jeans)? Read on for the 411 on the sweet stuff.
Carbohydrate is the technical term for all sugars, including both single-molecule simple sugars (like fructose), double-molecule sugars (like sucrose aka table sugar) and those strung together to form complex carbs like starch and fiber.
Carbs provide about four calories of energy per gram (except for fiber, which is calorie-free), and are the body’s preferred fuel source for high-intensity activities (like sports, running and weight training). While carbs are important for optimal performance and recovery and are the preferred food of the central nervous system, they are not actually essential nutrients. Translation: You won’t run into serious health risks if you don’t get a certain amount over time (unlike proteins and fats, which are).
Carbs are most commonly found in sweet and starchy plant-derived foods, including all fruits and veggies, grains, and processed products (think French fries, fruit juices and breads). Every single source of carbohydrate falls somewhere on the Glycemic Index, which is a scale of how fast the carbs from that food enter the bloodstream. High GI foods, like Gatorade and white bread, enter the bloodstream quickly, whereas lower GI foods, such as most fruits and whole grains, enter the blood at a slower and steadier pace. In carb consumption, timing is important, and it can depend on the type of carbs consumed.
To be clear, carbs are by themselves neither good nor bad. However, eating certain types of carbs at certain times and in certain amounts can lead to some undesirable consequences. When high GI carbs are consumed in high amounts (especially all at once), they cause an increase in the secretion of the hormone insulin, which can trigger fat gain.
And when you find yourself reaching for that fourth or fifth cookie, it’s not just your willpower that’s to blame. Consuming high quantities of high GI carbs doesn’t always deliver the “I’m full” response the body needs to control appetite. Chronic consumption of high GI foods may even resemble addiction. Removing them rapidly from a diet can trigger the same intensity of cravings. According to insulin researcher and champion strongman Dr. Mike Caruso, that long-term over-consumption of high GI carbs can lead to insulin resistance, a condition that can increase the likelihood of cardiovascular disease and type II diabetes.
But that doesn’t mean we need to banish life’s simple pleasures for good.
While carbs (especially high GI ones) come with their costs, they certainly have their benefits (besides just tasting great). Some carbs, especially those found in fruits, vegetables and whole grains, are packed into nutrient-dense foods that also provide loads of health-enhancing fiber. And then there are the effects of carbs on exercise and sport performance and adaptation.
Whether you’re a marathoner or a CrossFitter, carbohydrates are considered the go-to fuel source for high-intensity sport competition and training. If your goal is to have the best workouts, practice sessions and games, carbs are indispensable. They provide fuel for the central nervous system, which helps with mental energy for long and tough workouts. Even more profoundly for the fitness buff is that carbs can prevent muscle loss during training, and help stimulate muscle growth and fat loss if consumed during and especially after training. But, as with most things, context matters.
To get those carbs working in your favor, consider the following factors:
Timing: Most of your daily carbs should be eaten around your workout window. A good place to start is by eating 15 percent of your daily carbs in the meal before training, 15 percent during training (though probably not necessary if you’re doing a four-minute Tabata), 30 percent in the meal after training, and 20 percent in the meal after that. That leaves you with 20 percent of your daily carb intake to have at other times of the day.
Quantity: Since we have established timing, quantity per meal really depends on the quantity of carbs eaten per day. This depends highly on the amount of total exercise you do per day, but can range between one and three grams of carbs per pound of bodyweight, with two grams being a good start for most people.
Types: Carbs consumed during and right after workouts should be of a higher GI variety (as they grow muscle and help recovery more than low GI carbs at these times). However, the further out you are from your workout, the more the focus should be on lower-GI carbs. This way, you get the benefit of high GI carbs and low GI carbs precisely when both are best used.
An example of a typical carb consumption for an individual who weighs 150 pounds and is consuming one gram of carbs per pound of bodyweight per day is detailed below. Keep in mind, this general formula is for someone on the lower end of daily physical activity and workout volume. Individuals who train harder and longer will need more carbs per day, often somewhere between two and three grams per pound of bodyweight.
8:00 a.m. Breakfast: 20 g carbs from oatmeal
12:00 p.m. Pre-Training Meal: 20 g carbs from white rice
2:00 p.m. During-Training Meal: 20 g carbs from Gatorade
4:00 p.m. Post-Training Meal: 45 g carbs from low-fat Fig Newtons
6:00 p.m. Dinner: 30 g carbs from brown rice
9:00 p.m. Nighttime Snack: 10 g carbs from a small apple
This meal plan would of course also contain protein and fat sources, but by keeping those out you can see the pattern of amounts, timing and Glycemic Index typical of proper carb consumption. For individuals on lower carb diets, just plug in the total number of carbs per day into the above percentages to determine per-meal carb amounts. Some very low carb diets will have only 0.5 grams per pound of bodyweight per day or less, while some people, especially those playing multiple sports or training for endurance races, may consumed upwards of 4 grams per pound of bodyweight per day!
An important point to remember is that in large part, carb consumption is determined per day, so that on days you train hard, you’ll be consuming much more carbohydrates than on days you train light or don’t train. This is the basis for most approaches to carb cycling.
The bottom line: Carbohydrates are neither good nor bad just by themselves. The key is choosing them wisely, and timing them properly. Used optimally, carbs can enhance your fitness regimen — not derail it!