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Sugar…the word conjures up images of cotton candy,
candies, and tooth decay. But there's more to this stuff, then meets your sweet tooth. Similar to the notion that there are "better" protein sources for you, suffice it to say that there are "better" sugar or carbohydrate sources for you, depending on the circumstance. Think of it, we've got sucrose (table sugar), glucose, ribose (performance enhancer?), and fructose. Further, we can subdivide carbohydrates into low versus high glycemic foods or types.
So let's start first on a macro scale and ask (and answer) the question of how much carbs to you really need? Certainly, the "conventional wisdom" holds that carbohydrates should be the majority of one's caloric intake. On that I agree. However, how much carbohydrates should take up in your total calorie count is debatable. And it certainly should not be as high as typically consumed by endurance athletes (e.g., marathon runners, triathletes).
Glycemic index -- What Should You Do With It?
When it comes to planning your training meals, should you worry about the glycemic index. This is a measure of how quickly your blood glucose will rise after eating a specific kind of carbohydrate. Interestingly, simple sugars or carbohydrates did not always have a higher glycemic index than complex carbohydrates. For example, fruit and sweetened dairy products produces a blip in the glucose curve. Table sugar is higher.
But what's amazing is that bread and potatoes (a bodybuilder's favorite) register a very quick rise in blood glucose! So what should you do with this index? For bodybuilding, I'd say you should ignore it for the most part and here's why. Each meal should consist of a lean source of protein (e.g., skinless roast chicken breast), a complex carbohydrate (e.g., brown rice), fibrous vegetable (e.g., salad, broccoli, cauliflower, etc.), and a touch of unsaturated fat (e.g., olive oil mixed in a salad).
The fact that you eat a mixed meal negates the effects of the type of carbohydrate you eat. Even if it is a high glycemic carbohydrate such as potatoes. When it comes to the glycemic index, don't worry about it. Instead choose foods that are nutrient-dense foods. For instance, table sugar has a lower glycemic index than a potato. It's a no-brainer to figure out you should choose the potato over table sugar as your source of carbohydrate.
What Percentage Of Carbohydrates In A Meal Is Ideal?
I think this is one are in which we're too focused. There is no "ideal" ratio of carbohydrates. We need to start thinking in terms of carbohydrates consumed per unit body weight. For instance, if you're starving yourself on a 900 calorie diet, it is probable that your carbohydrate intake will be inadequate even if it makes up 70% of your total intake. But if you're gorging on a 5,000 calorie per day allotment, then a diet that consists of 40% carbohydrates should be more than enough to meet the needs of glycogen repletion.
Keep in mind that bodybuilders do not deplete their muscles of glycogen to the same extent that endurance athletes do. And since bodybuilders typically work different body parts daily, there is often plenty of time for an individual muscle or group of muscles to rest and recover.
How Much Carbohydrates Should You Consume?
According to noted carbohydrate researcher, Louise Burke, Ph.D., of the Australian Institute of Sport in Canberra Australia, "Specific information about an individual's training load and ability to recover between sessions may help fine tune carbohydrate intake targets. It is important, particularly in terms of judging everyday carbohydrate intake, to regard guidelines as an approximation rather than a fixed rule."
Dr. Burke recommends that very high level endurance athletes consume approximately 7-12 grams of carbohydrates per kilogram of body weight daily. That would be equal to a 200 lb bodybuilder eating 636-1,090 grams of carbohydrates daily! Suffice it to say that's way too high. Bodybuilders don't expend enough energy to warrant such high intakes.
On the low end, Dr. Burke recommends 5-7 grams of carbohydrates per kilogram body weight daily for "moderate intensity exercise of less than hour." Certainly, that would equal 454 grams of carbohydrates (5 g/kg) for a 200 lb. individual. If anything, I believe it would be best to err on the lower end of carbohydrate consumption and substitute it with a lean protein source. But as a general guide, perhaps 4-5 g/kg might be a good starting point.
Does Eating Before a Workout Have any Beneficial Effect?
It isn't clear that eating carbohydrates prior to training has a beneficial effect. For instance, scientists at Texas Christian University studied the effect of a high vs. a low pre-exercise carbohydrate diet on performance during multiple sets of resistance exercise. Eleven resistance-trained males performed bicycle exercise to deplete thigh muscle glycogen stores.
Subsequently, they consumed a high carbohydrate or a low carbohydrate diet for 2 days. Subjects then performed five sets each of squats, leg presses, and knee extensions (resistance = 15 RM) to failure. They found no differences in weight lifted or blood lactate levels. This isn't surprising in that weight-training exercises are not typically limited by muscle glycogen levels. So if you happen to eat before training, and it doesn't upset your stomach and you feel fine, then keep on doing it. However, if you are typically in a fasted state prior to training, then it may not make a difference if you consume carbohydrates prior to lifting.
Does Carbohydrate loading Build Muscle Faster?
One study measured muscle girth from nine weight-trained males before and after a control (standard isocaloric diet) and an experimental diet that consisted of high carbohydrate levels. The carb-loading scheme consisted of 3 days of intense weight-lifting while the subjects ingested a diet of 10% carbohydrate, 57% fat, and 33% protein, followed by 3 days of light weight-lifting and a day of rest while ingesting a diet of 80% carbohydrate, 5% fat, and 15% protein.
The control trial consisted of an identical weight-lifting regimen while subjects consumed an equal number of calories. What happened? Nothing. Carb-loading offered no additional advantage to enhancing muscle girth in bodybuilders over weight-lifting alone.
Glucose, Sucrose, And Maltodextrin: Good Fructose : Bad
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There is plenty of evidence showing that carbohydrate feeding during exercise (glucose, sucrose, and maltodextrin ) is effective in maintaining blood glucose concentrations and enhancing performance, particularly for endurance athletes.
Fatigue is often delayed by 30-60 minutes when you consume these sugars. Whether carbohydrate feeding is equally effective for anaerobic exercises such as resistance training is not completely understood. We do know that in sports such as ice hockey and soccer , the ingestion of carbohydrates during the game and at intermission can produce higher muscle glycogen concentrations and improve sprinting ability towards the end of the game.
Now I know that bodybuilders don't typically do sprints the way hockey and soccer players do, but the energy systems used by bodybuilding exercise are anaerobic in nature. So if had to take an educated guess, consuming a sports drink that contained glucose or maltodextrin might offset or delay fatigue.
Thus, you'll have energy left to perform the exercises you typically save for last (e.g. isolation exercises). But consuming carbohydrates during training probably won't make you stronger.
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Sugar Buster's Revenge?
In a recent article published in the prestigious American Journal of Clinical Nutrition, scientists investigated the role of carbohydrate intake on coronary heart disease in a population of 75,521 women. After adjusting for age, smoking, total caloric intake, and other coronary risk factors, this study found that dietary glycemic load was directly associated with risk of heart disease!
In other words, those who at the most high glycemic carbohydrates had an elevated risk of heart disease. In conclusion, they stated that "the current low-fat, high-carbohydrate diet recommended in the United States may not be optimal for the prevention of coronary heart disease and could actually increase the risk in individuals with high degrees of insulin resistance and glucose tolerance."
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Interestingly, fructose ingestion during exercise is not effective for enhancing performance. In addition, fructose is to be avoided because it may cause gastrointestinal distress.
Bottom Line
For your meals, it would be generally wise to avoid simple sugars and emphasize the nutrient-dense complex carbohydrates. During exercise, it might help offset fatigue if you consume a sucrose, glucose, or maltodextrin containing drink whereas fructose is to be avoided. With regards to immediate post-exercise eating, try to get in about 500 calories with at least 25-50% of this being protein (the rest carbs and a touch of fat). This should translate into speedier recovery. However, as with anything in science, more research is needed to confirm this.
About Jose Antonio
Dr. Antonio earned his Ph.D. at the University of Texas Southwestern Medical Center in Dallas. He also completed a post-doctoral fellowship at UTSWMC. He has published over three dozen scientific articles, six books and over 300 articles on exercise and nutrition.
Visit the Author's website at: www.JoseAntonioPhd.com
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