You can’t go wrong with carbohydrates

Sports Medicine: Carbohydrates are a misunderstood subject that has a bad reputation - our brain needs them to function.

311_pasta dish (photo credit: MCT)
311_pasta dish
(photo credit: MCT)
This is the third article in a series of articles on the subject of nutrition.
In the past two articles I introduced the topic of nutrition and expanded upon the subject of proteins.
I discussed how small amounts of high-quality protein combined with carbohydrates have been found to have a significant impact on the body’s protein synthesis, much more so than just eating large amounts of proteins.
It is with this information in mind that I will start our discussion on carbohydrates, a misunderstood subject that has a bad reputation.
Carbohydrates are the bread and butter of all foods. They are sugars and starches that are part of most everyday foods such as breads, fruits, vegetables, milk, honey, pasta, cereals, syrups, popcorn and of course, sugar.
Carbohydrates are what our brain functions on and supplies energy for our entire body. Our bodies favor this energy source that is broken down into glucose, which the blood brings to all the cells in our body.
Glucose is used for energy – it powers the cells in our body and helps power our muscles when we are involved in physical activity.
Our muscles use up our glycogen (a chain of glucose) when we work out. If athletes do not consume enough carbohydrates, they might not have enough glycogen stored in their body and will likely experience symptoms of fatigue.
Eating the right amount of carbohydrates is a smart choice to prevent glycogen deficiency.
An athlete’s performance relies greatly on the types of foods that are eaten several weeks before a competition.
If athletes are smart and monitor their diet to make sure they are receiving the right amount of nutrients – such as carbohydrates – in their diets, they should have enough glycogen stored in order to engage in physical activity.
Scientists are constantly coming up with new ways to classify and make sense of the many properties of carbohydrates.
In the past, carbohydrates were classified as complex or simple carbohydrates, which referred to the complexity of the sugars.
Complex carbohydrates correspond to food made of 3 of more sugars, and these were once thought to be healthier than simple carbohydrates.
However, this is an oversimplification and the classification only makes sense from a chemical perspective.
For instance, white bread and white potatoes are considered to be complex carbohydrates. However, most people would argue that these are not healthy carbohydrates at all.
A newer classification system called the glycemic index classifies carbohydrates based on how quickly they raise blood sugar levels in the body, in comparison to pure glucose.
In theory, foods with a low glycemic index, like chickpeas, should be digested slower, causing a smaller and softer change in blood sugar.
Foods that receive a score of 70 and above are considered to be high in glycemic index (for instance, french fries), while foods that receive a score of 55 and lower are considered to have a low glycemic index (like whole oats).
Besides needing more research to validate its credibility, the glycemic index does not take into account digestible carbohydrates, which is the amount of carbohydrates that are digested in the upper gastro-intestinal tract, that then enter the blood stream.
Therefore scientists developed another classification system that considers the amount of carbohydrates in food, as well as their effect on blood sugar levels. This system is called the glycemic load.
The glycemic load can be calculated by multiplying the glycemic index by the amount of carbohydrate contained in the food in question.
This is important because, for instance, a snickers bar would fall into the category of low glycemic index – and it is clearly not a healthy food choice. A healthy food, such as watermelon, is considered to have a high glycemic index.
The value of carbs Now that we have an adequate background to understand some of the classification systems that scientists are using to evaluate the quality of carbohydrates, it’s time to turn to the original question at state, which is the value of carbohydrates.
Many popular diets for the past several years have been treating carbohydrates like they are the plague. And studies have found that the Atkins diet, which severely restricts carbohydrates, is very effective.
However, when examined more closely, it appears that in some of these studies, the participants did not follow the diets as prescribed and ingested sometimes triple the number of carbohydrates recommended.
A lot of these studies found that whether or not participants stuck with their diet was a better predictor of continued and maintained weight loss, as opposed to what diet they went on.
Currently, health and nutrition experts recommend that between 55- 60% of the calories in our daily diet should come from carbohydrates, while only 30% should come from fats and only 10-15% from protein.
This is all contrary to what the average person believes they should be eating: a diet high in protein with little to no carbohydrates.
It should be noted that these numbers can vary depending on the type of activity an athlete is engaging in and should only be taken as general guidelines.
So what are some good carbohydrates? I recommend eating products that list as one of their first ingredients whole grains or whole oats. Whole wheat bread, for instance, is very healthy.
When it comes to rice, it’s a good idea to eat brown rice.
For pasta lovers, whole wheat pasta is a good option, or at least pasta that is a combination of half whole wheat and half white flour. Beans are an extremely good source of carbohydrates as well.
What is important is that you are receiving carbohydrates in your diet (between 55-60%) and not restricting it so that you are receiving no or little carbohydrates.
Remember, you can not go wrong with carbohydrates.
Next week, I will delve into the subject of hydration, emphasizing fluid intake and output during sport activity.
The above information is supplied by Yonatan Kaplan PT PhD (Candidate). Director, Jerusalem Sports Medicine Institute, Lerner Sports Center, Hebrew University.

For further details, e-mail: sportmed@zahav.net.il, call Yonatan at 054-463-9463 or visit www.jsportmed.com