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HPS 213
Fats
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Chapter Outline
I. What's the big deal about fats?
A. Fats are an important nutrient for both athletes and nonathletes.
1. They serve as a primary energy source at rest and during exercise of light
to moderate intensity.
2. Dietary fat provides the essential fatty acids required for normal physiological
functioning of the body.
3. Fats add flavor to foods.
4. Fats are calorie dense and capable of meeting the high daily energy needs of
athletes.
B. Fat is often maligned because of the well-known association of cholesterol and
saturated fats with heart disease.
1. The thought of body fat raises negative feelings, particularly in athletes, who
are aware of the potential impact excessive levels of body fat can have on sport
performance.
A. Fats are molecules that belong in a group of compounds known as lipids.
1. Lipids are organic, carbon-containing compounds that are hydrophobic (water
insoluble), lipophilic (fat soluble), and feel greasy to the touch.
2. Lipids are an energy-rich nutrient, yielding 9 calories per gram.
3. Lipids are found in foods of both plant and animal origin.
III. How are lipids (fats) classified?
A. The most important lipids fall into three main categories based on their
molecular structure: triglycerides, phospholipids, and sterols.
3. Triglycerides serve a number of functions in the body (considered an
essential nutrient)
a. Triglycerides serve as an important source of energy at rest and
during exercise.
b. Fats serve as an abundant energy reserve for the body
c. Visceral and subcutaneous fats provide protection for vital organs and
serve as a thermal and electrical insulator in the body.
d. Fats play an important role as carriers of substances (e.g., fat-soluble
vitamins) into the body and within the bloodstream.
e. Fats enhance the sensory qualities of foods.
f. Fat consumption at meals or snacks can enhance satiety.
h. All foods contain a combination of unsaturated and saturated fats
i. Saturated fats have been implicated in cardiovascular disease
because they contribute to atherosclerosis, the buildup of fatty
plaques on the interior arterial walls, particularly in the arteries of
the heart and neck.
C. Phospholipids
1. Characteristics
a. Found in both plants and animals.
b. Are both water soluble and fat soluble.
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c. Constitute the cell membranes of various tissues throughout the body.
d. Phospholipids are not essential, because the body can readily
synthesize them when needed.
D. Sterols
1. Characteristics
a. Their structure and function is quite different from both triglycerides
and phospholipids.
b. The most commonly known sterol is cholesterol.
c. Sterols are hydrophobic and lipophilic.
E. Artificial fats (fat substitutes)
1. Fat substitutes are popular in a variety of foods, including "luxury" foods
such as ice cream, salad dressings, and desserts.
2. The goal of fat substitutes is to decrease calories while maintaining the texture
and taste of foods.
3. Fat substitutes can be made from carbohydrates, proteins, or fats.
a. Carbohydrate-based fat substitutes are made from starches, fibers, and
gums. They contribute only 4 calories per gram (versus 9 calories per
gram in fat).
b. Whey protein from dairy or egg whites is used to produce protein-based
fat substitutes. Simplesse is an example.
c. Engineered fats manipulate the degree of saturation and fatty acid chain
length to produce similar qualities in food products as fats and oils.
Olestra, trade name Olean, is an engineered combination of sucrose and
fat that is nondigestable, and therefore calorie free.
IV. How much fat is recommended in an athlete's diet?
A. Fat is an essential nutrient in the diet.
B. No RDA or AI is set for total fat intake, because there is insufficient data to determine
a defined level of fat intake at which risk of inadequacy or prevention of chronic disease
occurs.
C. The Acceptable Macronutrient Distribution Range (AMDR) for fat intake has been set
at 20 to 35% of total energy for adults.
D. The American Heart Association promotes a slightly stricter range,
recommending a total fat intake of 30% or less of total energy intake in order to
decrease cardiovascular disease risk.
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F. In general, athletes report an average fat intake of 35% of total calories; however,
fat intake varies among athletes in different sports.
1. Endurance athletes tend to have lower fat and higher carbohydrate intake than
sprinters and short-distance runners.
2. Athletes dieting for weight loss and those involved in sports requiring weighins or judging on appearance also tend to have lower fat intake.
3. Collegiate athletes, many of whom are living away from home, may consume
too much dietary fat due to an over-reliance on fast foods.
a. Over-consumption of fats usually leads to ingesting too many calories.
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b. Excessive calories can lead to increases in body fat levels; in most
cases, this has detrimental effects on sport performance.
G. Athletes should focus not only on the total amount of fat in their diet, but also on the
type of fat consumed.
1. Saturated and trans fats should be kept to a minimum. These fats have been
shown to be the most detrimental to cardiovascular health because they increase
cholesterol levels.
2. Monounsaturated and polyunsaturated fats are beneficial to health,
leading to more favorable cholesterol levels and possibly aiding in the prevention
of cancer and arthritis.
H. A diet can be too low in fat.
1. Because dietary fat contributes a significant amount of calories per gram, low
fat intake can negatively affect energy balance.
2. Deficiency in essential fatty acids can result from severe restriction of dietary
fat intake.
I. A diet can be too high in fat. Consuming too much fat can lead to the consumption
of too many total calories, resulting in weight gain in the form of body fat.
V. Which foods contain fat?
A. Fats are found within most food groups of the MyPyramid food guidance system;
however, the richest sources of fat are found within the oils category (Table 4.2).
B. Fat in the grains group
1. Whole grains, such as oatmeal, barley, bulgur wheat, millet, and spelt, contain
less than 1 to 3 grams of fat per serving. The fat in these grains is mainly
unsaturated.
2. Foods such as biscuits and croissants are high in fat, with a larger percentage
coming from saturated and trans fats.
3. Training Table 4.1 provides some tips on including low-fat grains in meals.
C. Fats in the fruit and vegetable groups
1. In general, fruits and vegetables contain minimal to no fat.
2. Certain vegetables, such as avocados and olives, contain a considerable amount
of fat, although it is mainly unsaturated.
3. Training Table 4.2 provides some tips on using fruits and vegetables rich in
unsaturated fats.
D. Fats in the milk/alternatives group
1. Full-fat dairy products, such as whole milk or hard cheeses, may contain 8 to
10 grams of fat per serving, with a high percentage coming from saturated fat.
2. Low-fat or nonfat dairy products, such as skim milk, low-fat yogurt, and
cottage cheese, may have only 1 to 4 grams of fat or less per serving.
3. Most soy, rice, or other dairy-alternative products contain approximately 1 to 6
grams of fat per serving. The fats in dairy alternatives are mainly unsaturated fats,
and therefore excellent substitutes for full-fat dairy products.
4. If fortified, low-fat and nonfat dairy products, as well as dairy-alternative
products, contain the equivalent amounts of calcium and vitamin D as their fullfat counterparts.
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5. Training Table 4.3 provides tips on including low-fat milk/alternative products
in meal planning.
E. Fats in the meat and beans/alternatives group
1. In general, beef contains a higher quantity of fat and a higher percentage of
saturated fat than most other foods in this group.
2. Chicken, turkey, and pork contain moderate amounts of total fat and saturated
fat.
3. Some fish are very lean, such as orange roughy, whereas others are higher in
fat, such as salmon. However, a majority of the fat in fish is unsaturated.
Additionally, the fats from some fish are a rich source of omega-3 fatty acids.
4. Eggs, especially egg whites, are relatively low in fat.
5. Nuts and seeds contain higher levels of fat, but similar to fish, they contain
mainly unsaturated fats.
6. Legumes are very low in fat and the little they do contain is unsaturated.
7. Soy products range from low-fat choices, such as tofu, to higher fat choices,
such as soy nuts, but they also consist mainly of unsaturated fats.
8. Training Table 4.4 provides meal-planning tips for using low-fat meat and
beans/alternative products.
F. Fat in the oils group
1. The best choices within this group are unsaturated oils, such as olive, canola,
flax, and sesame oils.
2. Saturated and trans fatty acids, which are found in butter, margarine, snack
items, desserts, and other fried or processed foods, should be kept to a minimum.
3. Training Table 4.5 provides some healthier options within the oils group.
VI. How can the percentage of calories from fat be calculated for specific foods?
A. All athletes should be aware of how to calculate the percentage of calories from fat in
various foods in order to make healthy food choices (see Figure 4.8).
2. The total calories per serving and total calories from fat are listed at the
top of the Nutrition Facts label on any food product.
C. If the calculated percentage is less than 35%, the athlete knows the product fits
within healthy eating guidelines.
1. Athletes should keep in mind that the recommendation for 20 to 35% of total
calories coming from fat is a guideline for the overall diet—not necessarily for
every individual food eaten in the diet.
2. Sometimes athletes will take this recommendation too far and unnecessarily
exclude all foods that do not fall into this category.
3. Athletes should use the percentage of calories from fat, along with other
nutritional benefits or drawbacks, to fully evaluate a food or beverage in the
context of an entire meal.
D. If the athlete is trying to determine the percentage of calories from saturated fat, trans
fat or obtaining nutrition information about a product from sources other than the food
label, the information needed is:
1. Total calories per serving
2. Total grams of fat, saturated fat, or trans fat per serving
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a. One extra step is required before the numbers can be plugged into the
equation listed earlier.
b. Multiply the number of grams of fat, saturated fat, or trans fat by 9
(because there are 9 calories per gram of any type of fat) to obtain the
number of calories from fat.
VII. What's the big deal about cholesterol?
A. On the basis of ongoing research in the area of cardiovascular health, high blood
cholesterol has been strongly associated with a higher risk for cardiovascular disease.
1. Blood cholesterol levels have been targeted as one of the first lines of defense
in the prevention of cardiovascular disease.
2. One of the best ways to modify blood cholesterol levels is to adapt lifestyle
factors, such as exercise and diet, specifically dietary fat, saturated fat, and
cholesterol consumption.
B. Cholesterol is a sterol.
C. Cholesterol is found only in animal products (see Table 4.4).
1. All meats contain cholesterol; organ meats contain the highest amounts.
2. Eggs and dairy products also contain cholesterol; nonfat dairy options contain
the least.
3. Some breads, muffins, and baked goods will have cholesterol if they were made
with eggs and/or dairy products.
4. Plant products, such as fruits, vegetables, whole grains, legumes, and soy, are
cholesterol free.
a. These foods do contain plant sterols, however, which have a similar ring
structure to cholesterol.
b. Plant sterols or stanols have recently been investigated for their
potential as cholesterol-lowering substances.
VIII. How can fats affect daily training and competitive performance?
A. Fats are a major fuel source for muscle cells.
B. Fats are the primary source of energy at rest, during low- to moderate-intensity
activities (Figure 4.11), and during recovery periods between intense bouts of
activity.
C. Endurance training improves the body's ability to utilize fats for energy.
1. The body's ability to mobilize fats from adipocytes is enhanced, thus making
more fatty acids available to the working muscle.
2. The working muscle's capacity to oxidize/utilize fats is improved due to:
a. Increased muscle blood flow.
b. Improved transport of fats into the muscle cells.
c. Larger and more numerous mitochondria.
d. Increased quantities of enzymes involved in fat metabolism.
D. However, fats are not the body’s fuel of choice at higher levels of exercise intensity.
1. Fats have a relatively slow rate of adenosine triphosphate (ATP)
production compared to carbohydrates.
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IX. What type, how much, and when should fats be consumed before exercise?
A. Researchers have examined the ability of fat to enhance performance when consumed
in the hours, days, or weeks before training or competition:
1. A single high-fat meal prior to exercise
a. Theory: A high-fat meal prior to competition will increase fatty acid
levels in the blood and in turn enhance endurance performance compared
to a high-carbohydrate meal.
b. The majority of studies have not found any benefit to ingesting
high-fat meals prior to competition when compared to highcarbohydrate meals.
c. Many athletes find that eating a meal high in fat 1 to 4 hours prior
to an exercise session, or especially a competition, leads to
gastrointestinal distress, including bloating, diarrhea, stomach
cramping, and a sense of fullness.
d. It is not recommended that athletes eat a high-fat meal immediately
prior to exercise due to the potential for gastric upset.
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B. Recommendations for fat intake prior to exercise
1. Athletes need to experiment with the best pre-exercise meal for their
digestive system and sport.
2. Fat will create a feeling of satiety, preventing an athlete from feeling hungry
before exercising.
3. Consuming too much fat 4 hours or less prior to exercise can cause bloating,
intestinal cramping, or diarrhea.
4. Meals and snacks within 4 hours of training sessions and/or competitions
should be low in fat and focused mainly on the unsaturated fats.
5. Refer to Training Table 4.7 for pre-exercise meals and snacks that contain a
small amount of fats and maintain a balance of carbohydrates and protein.
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