I talked to Josh yesterday and he encouraged me to take in lots of good clean carbs and proteins to recover from my activities. Since I am not a food guru, I asked him to clarify a clean carb. See below his response. Great info!
HAPPY HUMP DAY!
Carbohydrates are present in various types of food we eat and are the main source of energy for the body for most people. Carbohydrates release 4 calories of energy per gram when used by the body as a source of energy. There are 3 basic types of carbohydrates, simple, complex and very complex. Out of these, the last two types are essential for a healthy diet and should be a part of any healthy dietary program.
1. Simple Carbohydrates - (also called sugars) : Simple carbohydrates can be found in white table sugar, preservatives, candies, coke, cake, juice concentrates, honey and glucose syrup. They are made up of single or double molecules and are quickly absorbed into the blood stream. Glucose is the simplest food and is absorbed into the blood stream as blood glucose.
2. Complex Carbohydrates : Foods that are high in complex carbohydrates include bread, pasta, rice, beans, vegetables and potatoes. This type of carbohydrates is made up of complex molecules and the body requires time to digest them, which means that we feel full for a longer time period after eating them.
3. Very Complex Carbohydrates : also known as Fiber This type of carbohydrates, found in whole meal bread and phsylum husk etc. adds bulk to our food which helps in digestion. Fibers help to ease the flow of food through the intestines and reduce the risk of diabetes and lower cholesterol. 30-35 grams of fibers a day is beneficial for the body. Very complex carbohydrates have an extremely complex molecular structure.
Carbohydrates form a major part of the diet of an athlete (or any individual) and it is very important for the sports nutritionist to understand the types of carbohydrates and the effect that they have on the athlete’s body. Different types of carbohydrates have differing effects on the performance and functioning of the body. This can vary from enhancing the athlete’s performance on the one hand to enhancing the chances of disease on the other.
Carbohydrates are converted into glucose by the body. The human body can absorb only glucose, galactose or fructose (all simple carbohydrates) into the blood stream for use as a means of generating energy. The glucose derived from food is used by the body in the following ways:
1. To generate energy by burning the glucose
2. To store the glucose in the liver and muscles as glycogen. The liver can hold up to 100 grams of glycogen and the muscles can store up to 600 grams of glycogen. The glycogen in the liver supplies energy to the whole body and the muscle glycogen supplies energy only to the muscles.
3. Excess glycogen is stored as fat by the liver. Once the glycogen has been converted into fat, it cannot come back to its original glycogen state.
How Carbohydrates Affect Athletic Performance
Carbohydrates have an important part to play in the performance of an athlete. The following are some of the functions of carbohydrates:
1. They serve as the main energy source for an athlete, especially at times of heavy exercise.
2. The body gets its energy from glucose and muscle glycogen. When an athlete trains hard, the carbohydrates are exhausted very fast and must be replenished to maintain muscle glycogen levels.
3. Carbohydrates help in building stamina and endurance in the body.
4. Taking adequate carbohydrates prevents the use of proteins as an energy source for the body. When the carbohydrates are exhausted during intense exercise, the body begins to use the reserves of proteins for its energy requirements. Proteins are required for other essential body functions and can be saved by consuming adequate amounts of carbohydrates.
5. When carbohydrates break down, they leave behind byproducts that help to break down fat in the digestive process. This is particularly important for athletes.
6. Carbohydrates are also a source of energy for the brain and the central nervous system (both of which rely on blood glucose for energy). Lack of carbohydrates can lead to loss of concentration and fatigue.
Carbohydrates Improve Performance
After a heavy workout, the reserves of muscle glycogen in the body are exhausted. The replenishment of this glycogen is essential after the exercise session and, therefore, it is essential for athletes to eat enough carbohydrates after exercise to build up the glycogen reserves for the next workout. It is advisable to eat carbohydrate rich foods within 1-2 hours after the exercise to replenish the glycogen stocks and avoid injury. Training also increases the ability of the muscles to store more glycogen and thus helps them to train longer and harder. The recommended consumption of carbohydrates according to the food guide pyramid is 6-11 servings of carbohydrate rich foods which works out to about 40-60% of the total daily calorie intake. The carbohydrate intake for athletes should be mostly in the form of complex carbohydrates and simple carbohydrates from natural sources. During heavy training, the carbohydrate intake of an athlete should go up to 55-70% of the total calorie intake depending upon the nature of exercise.
A Classification of Some Foods
The carbohydrate content (grams) of some simple foods are mentioned below
Pudding (1/2 cup) – 30, Black eye peas (1/2 cup) – 22, Apple – 21, Banana – 27,
Grapes (1 cup) – 28, Carrot – 8, Peas (1/2 cup) – 12, Navy beans (1 cup) – 48,
Potato (large) – 50, White bread (1 slice) – 12.5, English muffin –39, Rice (1 cup) - 50
3.1 Carbohydrates and the Glycemic Index
Carbohydrates are converted into glucose in the body. Glucose gives the body energy to carry on daily activity and during sports activity. The Glycemic Index (GI) is the blood glucose response from a carbohydrate food and takes the form of a ranking from 1 to 100. The GI tells us about the rate of absorption of the carbohydrates in the food. (i.e. whether they absorb fast, at a medium pace or slowly). Foods with a high GI get absorbed into the blood stream at a fast pace and provide glucose to the body faster. Foods with a low GI are absorbed at a much slower pace and provide blood glucose to the body over an extended time period.
How is the GI Calculated
The GI is calculated in the laboratory by feeding participants with 50 grams of digestible carbohydrates and then measuring their blood glucose level over a period of 2 hours. The participants are then fed with 50 grams of glucose sugar for comparison purposes. The GI is an index which is calculated by dividing the glucose response (glucose AUC) of the test food by the glucose AUC for the reference food (glucose sugar). The results are usually averaged out after taking samples from 10 candidates.
How to Calculate GI - GI is calculated in the laboratory by feeding the participants with 50 grams of digestible carbohydrates and then measuring their blood glucose level over a period of 2 hours. The participants are then fed with 50 grams of glucose sugar for comparison purposes. GI is an index which is calculated by dividing the glucose response (glucose AUC) for the test food by the glucose AUC for the reference food (glucose sugar). The results are usually averaged out after taking samples from 10 participants.
Foods with High GI - These foods lead to a fast rise in the level of blood sugar followed by a quick fall in the blood sugar levels. Sudden increases in the blood glucose levels require the pancreas to secrete additional insulin, which results in a sharp fall in the blood glucose level over a period of 1-3 hours. High GI foods lead to high levels of blood glucose and insulin levels in the body which could lead to insulin resistance and in some cases diabetes.
Foods with Low GI - These foods lead to a gradual rise in the level of blood sugar followed by a gradual fall in the blood sugar levels. Eating low GI foods results in a sustained level of blood glucose for a longer period of time and does not require the pancreas to secrete more insulin. The effect of low GI foods is to give a fuller feeling (resistance to hunger) for a longer time to the individual, and can assist weight loss efforts. The problem of insulin resistance is also avoided with low GI foods.
The Importance of GI to an Athlete
An athlete should quickly replace glycogen stores after intense exercise. The speed at which the stores are replenished is where the GI of the food being eaten comes into the picture. Rapid replenishment of glycogen is a must for athletes who have to perform repetitively after small time intervals (e.g. during heats in sprinting). Such athletes do not have much time before the next event and must eat foods that immediately shoot up their blood glucose levels (high GI foods). Consuming high GI carbohydrates (approx. 1 gram per kg of body weight) within 2 hours of the exercise speeds up glycogen replenishment and recovery. In sports that require performance for long durations (over 1 hour), it is wise to keep the athlete replenished with glycogen consistently throughout the day. This can be done by eating low GI foods 2 hours before the exercise or competition. The food will slowly supply blood glucose and shore up the stores of glycogen and keep the athlete full of energy for longer. It is always a good idea to keep eating carbohydrates throughout a competition to keep the glycogen and blood sugar levels high and constant.
The GI of some common foods (The GI of glucose which is always used as the reference food is 100): GI is measured on a scale where the GI of glucose is 100. Foods have been categorized as low, medium and high GI foods.
Low GI = 55 or less,
Medium GI = 56 - 69,
High GI = 70 or more
Breakfast Cereals
Oatmeal 49
Shredded Wheat 67
Quaker Puffed Wheat 67
Grains
Brown Rice 55
Long Grain White Rice 56
Short Grain White Rice 72
Noodles (instant) 46
GI of Fruit
Apple 38 Banana 55
Grapes 46
Papaya 58
Pear 38
Pineapple 66
Plum 39
Watermelon 103
GI of Vegetables
Broccoli 10
Cabbage 10
Carrots 49
Corn 55
Green Peas 48
Lettuce 10
Mushrooms 10
Onions 10
Potato (baked) 93
Potato (mashed, instant) 86
Parsnips 97
Sweet Potato 54
GI of Legumes/Beans
Baked Beans 48
Broad Beans 79
Lentils 30
Red Kidney Beans 27
Soy Beans 18
GI of Breads, Muffins & Cakes
Bagel 72
Blueberry Muffin 59
Croissant 67
Donut 76
White Bread 70
Whole Wheat Bread 69
GI of Pasta
Spaghetti 43
Ravoli (meat) 39
Macaroni 47
Rice Vermicelli 58
GI of Dairy Foods
Milk (whole) 22
Milk (skimmed) 32
Ice Cream (whole) 61
Yoghurt (low-fat) 33
GI of Snack Foods
Cashews 22
Chocolate Bar 49
Corn Chips 72
Jelly Beans 80
Peanuts 14
Popcorn 55
Potato Chips 55
Glycogen Loading
Carbohydrates help in producing glycogen which is stored in the muscles and used at the time of intense physical exercise. Additional stores of glycogen can help an athlete increase endurance. Glycogen loading is a technique used by athletes to enable the body to store more than normal amounts of glycogen in the muscles. This practice helps in increasing the endurance of an athlete at the time of a sports event. The technique involves the following steps:
1. The athlete reduces the intake of carbohydrates for several days by eating more fats and protein rich food.
2. The muscle glycogen in the body is also depleted through heavy physical workouts.
3. The exercise is reduced abruptly to lower intensities and the carbohydrate intake is increased.
4. The muscle glycogen levels shoot up by 2 to 4 times of the normal level and the endurance of the athlete increases as a result.
Glycogen loading is a common practice, but in some cases, it can lead to heart irregularities and should be practiced with caution. Since muscle glycogen is used only for endurance sports (such as long distance running) or where the athlete is required to exert for over 1 hour. It is not of any use to resort to this technique for short duration sports. For every gram of glycogen added to a muscle, the muscle will also gain 2.4 grams of water. This can be helpful in some sports where a larger muscle size is important, but can also be a negative factor in some sports where the body weight of the athlete should be kept low.
Carbohydrates for Performance
There is plenty of sound scientific evidence to suggest that endurance athletes should eat carbohydrates, fats and proteins in the following proportions:
60-65% carbohydrates,
20-25% fats, and
15-20% proteins
The nutritionist must make the above statistics clear to the client since there may be a lot of other influencing factors at play such as companies selling wonder drugs or protein powders that emphasize the benefits of increasing protein intake. Such companies would not like to state simple truths that have been known for years because it would hinder their sales pitch. The theory behind sports nutrition is fairly simple and you should always try to keep it simple for your client as well. It is also your duty to inform your client about the unhealthy effects of supplements and wonder diets selling in the market. Many athletes are overawed by the hype around proteins. There is no doubt that proteins coupled with proper exercise will lead to muscle gain. However, simply taking a diet rich in proteins will not help many types of athletes. A diet that is too rich in proteins and lacking in carbohydrates will deplete the muscle glycogen levels of an athlete resulting in the loss of energy and performance. Some athletes rely on excessive fats to build energy reserves during exercise. However, fat can not be broken down fast and as the intensity of the exercise increases, carbohydrates become the main source of fuel and the rate of fat burning remains constant.
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