could you summarize this? 

Personal trainers are often asked about supplementation and the extent to which nutrients,
compounds, and products influence health and fitness goals. Supplements make it easier to
consume adequate amounts of vitamins and minerals, which are essential nutrients the
body needs in small amounts. Even though small amounts are required, it can be difficult to
sustain a broad, healthy nutrition plan consisting of nutrient-rich foods such as fruits,
vegetables, whole grains, low-fat protein, and legumes. While it is not the responsibility, or
within the scope of practice, of a personal trainer to prescribe and recommend dietary
supplements, knowledge of dietary supplements can help fitness professionals provide
appropriate supplement guidance, increasing value and support for members and clients.
Fitness professionals can help clients navigate misinformation and understand what they
should look for to ensure their dietary supplements are safe, effective, of a superior quality,
and free from contaminants, banned substances, or impurities.
WHAT IS A DIETARY SUPPLEMENT?
The National Institutes of Health defines a dietary supplement as a product that contains
one or more dietary ingredients and is intended to supplement a person’s nutrition plan.
Before digging into commonly used dietary supplements, it is important to know that the
Federal Food, Drug, and Cosmetic Act defines a dietary ingredient as a vitamin, mineral,
herb, botanical, or amino acid. It is a substance used to supplement a nutrition plan by
increasing the total dietary intake. This could be a concentrate, metabolite, constituent,
extract, or combination of the preceding substances. Common supplements may be
designated as performance supplements, nutritional supplements, ergogenic aids, and
botanical supplements.
Table 15.1 Supplement Categories
TYPE
NUTRITIONAL
SUPPLEMENTS
PERFORMANCE
SUPPLEMENTS
ERGOGENIC
AIDS
BOTANICAL
SUPPLEMENTS
Description
Natural or synthetic
nutrients intended
to supplement a
nutrition plan
Vitamins, minerals,
proteins, herbs,
and amino acids
consumed to promote
metabolic and physical
performance and
recovery
Compounds
consumed to
specifically
enhance
performance
during exercise or
competition
Made from plant
parts or extracts
and intended to
supplement a
nutrition plan
VITAMINS:
Organic compounds
essential for normal growth
and nutrition.
MINERALS:
Elements in food that the
body needs to develop and
function.
DIETARY
SUPPLEMENT:
A product containing one
or more dietary ingredients
that is intended to
supplement a person’s
nutrition plan.
DIETARY INGREDIENT:
A vitamin, mineral, herb,
botanical, or amino acid
used to supplement a
nutrition plan to increase
total dietary intake of
ingredients.
HERB:
Any plant with leaves,
seeds, or flowers used for
flavoring food and medicine.
BOTANICAL:
Substance obtained from a
plant and used as an additive.
AMINO ACID:
A simple organic compound
known as the building block
of proteins.
PERFORMANCE
SUPPLEMENTS:
Supplements intended
to help enhance athletic
performance.
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Supplements can come in many different forms including capsules, tablets, liquids, and
powders.
Unlike prescription drugs, dietary supplements are not required to be tested for safety or
effectiveness before going to market. While the Food and Drug Administration (FDA) is not
in the business of approving dietary supplements, it can “disapprove” them and remove a
product that is shown to be harmful or a public health risk. Also, it is illegal to market a
dietary supplement product as a treatment or cure for a specific disease or as being able to
alleviate the symptoms of a disease.
NUTRITIONAL DEFICIENCIES
There are many elements to an effective nutrition plan, and supplements may serve as a vital
component. These elements include nutrition awareness, food quality and portion control,
eliminating nutrient deficiencies, and engaging in regular exercise. Nutrient deficiencies can
be problematic, contributing to chronic conditions. According to the World Health Organization
(WHO), iron deficiency is one of the most common nutrient deficiencies contributing to
worldwide anemia. There are many conditions that can cause anemia, among them are
genetic factors, impaired metabolism, heavy menstruation, and even intestinal diseases.
Anemia affects one-third of the world’s population and contributes to increased morbidity and
mortality. Supplementation may help eliminate nutrient deficiencies such as this.
There are special situations where some individuals may be at risk of developing nutritional
deficiencies, so there are cases where taking dietary supplements can be a good idea.
Individuals restricting calories by consuming less than 1,200 Calories a day are at risk of
missing out on important nutrients. Individuals with food allergies or intolerances are more
likely to avoid complete food groups such as whole grains or dairy, respectively, and they
will have to obtain nutrients from alternative sources. Additionally, people who spend little
to no time outside under the sun, or those who consistently use sunscreen outside, may
eventually create a vitamin D deficiency. Also, women contemplating pregnancy and those
who are pregnant will require additional folate to prevent certain birth defects and more iron
to increase the blood supply for a growing baby.
ERGOGENIC AIDS:
Substances that enhance
energy production and
provide athletes with a
competitive advantage.
FOOD AND DRUG
ADMINISTRATION
(FDA):
A US federal department
that regulates the
production and distribution
of food, pharmaceuticals,
tobacco, and other
consumer products.
ANEMIA:
A condition marked by a
deficiency of red blood cells
or of hemoglobin in the
blood resulting in extreme
fatigue.
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CHAPTER 15 | Supplementation
NUTRIENT REQUIREMENTS
Every five years, the United States Department of Health and Human Services and the United
States Department of Agriculture (USDA) publish the Dietary Guidelines for Americans. The
Dietary Guidelines for Americans provides science-based advice on nutrient needs to promote
optimal health and reduce the risk of chronic disease. Its focus is on providing quantitative
guidance about foods, and it emphasizes giving recommendations about food and beverages.
In contrast, the Food and Nutrition Board, an arm of the National Academy of Medicine, has
set standards for nutrient requirements in the form of Dietary Reference Intakes (DRIs). A
subgroup of these DRIs is the Recommended Daily Allowance (RDA), which provides a safe
and adequate reference for most people to decrease their risk of chronic disease. The RDA
specifies the amount of a vitamin or mineral that is needed to maintain health and stay
nourished. It is based on an average daily level of intake sufficient to meet the nutrient
requirements of most people, in this case, 97–98 percent of healthy people. RDAs were
originally set to be a standard that would serve as a goal for optimal nutrition. These
references are meant to be applied to people of different ages. According to the USDA, many
people do not meet the RDAs for many micronutrients and these RDAs are not intended for
individuals with deficiencies.
NUTRITIONAL SUPPLEMENTS
According to a 2019 consumer survey given by the Council for Responsible Nutrition,
supplement use is at an all-time high with multivitamins/minerals (MVMs) being the most
used. Most individuals take supplements to maintain or improve health and to help fill small
nutritional gaps. Additionally, of all the supplements that a client may ask about, the most
common is typically an MVM formula. The notion that a person can get everything they need
by eating a balanced diet is confounded by many factors such as current health status, food
intake, and lifestyle. The 2020–2025 Dietary Guidelines for Americans states that the general
population in the US fails to meet the recommendations for food groups and nutrient intakes.
This means most Americans have eating patterns that are not aligned with dietary
recommendations. Moreover, they are not meeting their intake needs for nutrients such
as vitamins and minerals.
DIETARY REFERENCE
INTAKES (DRIS):
A set of standards
estimating how much of a
nutrient should be ingested
that is used in planning
eating patterns for healthy
individuals.
RECOMMENDED DAILY
ALLOWANCE (RDA):
The average daily level of
intake that is sufficient to
meet the needs of nearly all
(97%-98%) healthy people.
MULTIVITAMINS/
MINERALS (MVMS):
Supplements or pills
containing a combination of
vitamins and minerals.
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Supplements are not intended to cure or treat medical conditions, and that application
exceeds a personal trainer’s scope of practice. However, MVM supplement use is warranted
to prevent long-term nutrient insufficiencies associated with premature aging and higher risk
of age-related decline. As clients age, their nutritional needs increase, which means being
aware of what foods are consumed becomes critical. MVMs offset deficiencies that worsen
from inadequate food intake and certain medications.
DAILY VALUES: VITAMINS
The Daily Value (DV) is what an individual typically sees on the label of a dietary supplement.
It was developed by the FDA to help the consumer determine how much of a nutrient is in a
serving when compared to the requirement for that nutrient. Labels are expressed with the
“%DV” symbol and show the percentage of a serving that contributes to obtaining the total
DV. For example, if the DV for a vitamin is 500 micrograms (mcg) and the container for a
supplement indicates the supplement has 50 mcg in a serving, then an individual will meet
10 percent of their need for the day with one serving. The DV is meant to make it easier for
individuals to understand what their daily dietary needs are. Since labels are small, the
number is just one value and can sometimes be the same as the RDA.
Table 15.2 RDA for Vitamins
VITAMIN PURPOSE FOODS DV
Biotin • Energy storage
• Protein,
carbohydrate,
and fat
metabolism
Avocados
Cauliflower
Eggs
Fruits
Whole grains
Liver
Pork
Salmon
30 mcg
Folate/Folic
acid
Important for
pregnancy
• Prevents birth
defects
• Protein
metabolism
• Red blood cell
formation
Asparagus
Avocado
Beans and
peas
Enriched grain
products
Green leafy
vegetables
Orange juice
400 mcg DFE
DAILY VALUE (DV):
Reference amounts
expressed in grams,
milligrams, or micrograms
of nutrients to consume or
not to exceed each day.
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CHAPTER 15 | Supplementation
VITAMIN PURPOSE FOODS DV
Niacin • Cholesterol
production
• Converts food
into energy
• Digestion
• Nervous system
function
Beans
Beef
Enriched grain
products
Nuts
Pork
Poultry
Seafood
Whole grains
16 mcg
Pantothenic
acid
• Converts food
into energy
• Fat metabolism
• Hormone
production
• Nervous system
function
• Red blood cell
formation
Avocados
Beans and
peas
Broccoli
Eggs
Milk
Mushrooms
Poultry
Seafood
Sweet potatoes
Whole grains
Yogurt
5 mcg
Riboflavin • Converts food
into energy
• Growth and
development
• Red blood cell
formation
Eggs
Enriched grains
Meats
Milk
Mushrooms
Poultry
Seafood
Spinach
1.3 mcg
Thiamin • Converts glucose
into energy
• Nervous system
function
Beans and peas
Enriched grain
products
Nuts
Pork
Sunflower
seeds
Whole grains
1.2 mcg
Table 15.2 RDA for Vitamins (CONT)
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VITAMIN PURPOSE FOODS DV
Vitamin A • Growth and
development
• Immune function
• Reproduction
• Red blood cell
formation
• Skin and bone
formation
• Vision
Cantaloupe
Carrots
Dairy products
Eggs
Fortified cereals
Green leafy
vegetables
Pumpkin
Red peppers
Sweet potatoes
900 mcg RAE
Current RDAs
from the DRI
reports for
vitamin A are
expressed as
micrograms of
retinol activity
equivalents
(RAE).
Vitamin B6 • Immune function
• Nervous system
function
• Protein,
carbohydrate,
and fat
metabolism
• Red blood cell
formation
Chickpeas
Fruits (other
than citrus)
Potatoes
Salmon
Tuna
1.7 mg
Vitamin B12 • Converts food
into energy
• Nervous system
function
• Red blood cell
formation
Dairy products
Eggs
Fortified cereals
Meats
Poultry
Seafood
2.4 mcg
Vitamin C • Antioxidant
• Collagen and
connective
tissue formation
• Immune function
• Wound healing
Broccoli
Brussel sprouts
Cantaloupe
Citrus fruits
and juices
Kiwi
Peppers
Strawberries
Tomatoes and
tomato juice
90 mg
FORTIFIED:
Having had vitamins or
other supplements added
so as to increase the
nutritional value.
Table 15.2 RDA for Vitamins (CONT)
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CHAPTER 15 | Supplementation
VITAMIN PURPOSE FOODS DV
Vitamin D
Deficient
in most
Americans
• Blood pressure
regulation
• Bone growth
• Calcium balance
• Hormone
production
• Immune function
• Nervous system
function
Eggs
Fish
Fish liver oil
Fortified cereals
Fortified dairy
Fortified
margarine
Fortified orange
juice
Fortified soy
beverages
Sunlight
20 mcg
Vitamin E • Antioxidant
• Formation of
blood vessels
• Immune function
Fortified cereals
Fortified juices
Green
vegetables
Nuts and seeds
Peanuts
Vegetable oils
Wheat germ
15 mg AT
Current RDAs
from the DRI
reports for
vitamin E are
expressed as
milligrams of
alpha-tocopherol
(mg AT).
Vitamin K • Blood clotting
• Strong bones
Broccoli
Collard greens
Kale
Spinach
Turnip greens
120 mcg
Note: AT = alpha-tocopherol; DFE = dietary folate equivalent; mcg = microgram; mg =
milligram; RAE = retinol activity equivalent (adapted from FDA fact sheet)
Table 15.2 RDA for Vitamins (CONT)
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DAILY VALUES: MINERALS
Minerals are inorganic elements found in soil and water that the body needs to function properly
and develop. The body requires a certain amount of minerals to build strong bones and convert
food into energy. A client’s nutrition plan should provide all the minerals the body needs to
maintain cell and immune system function, but for various reasons, individuals can become
deficient. Having a poor nutrition plan over a prolonged period can lead to mineral deficiencies.
In addition, the ability of the body to absorb calcium typically decreases with age, so regular
calcium supplementation will become important as people get older. Each mineral serves its own
purpose, is found in a variety of foods, and is required in different amounts.
Table 15.3 RDA for Minerals
MINERAL PURPOSE FOODS DV
Calcium • Blood clotting
• Bone and teeth
formation
• Constriction and
relaxation of
blood vessels
• Hormone
secretion
• Muscle
contraction
• Nervous system
function
Almond, rice,
coconut, and hemp
milks
Dairy products
Fortified cereals
Fortified juices
Fortified soy
beverages
Green vegetables
Tofu
1,300 mg
Chloride • Acid-base
balance
• Converts food
into energy
• Digestion
• Fluid balance
• Nervous system
function
Celery
Lettuce
Olives
Rye
Salt substitutes
Seaweeds
Table salt and sea
salt
Tomatoes
2,300 mg
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CHAPTER 15 | Supplementation
MINERAL PURPOSE FOODS DV
Chromium • Insulin function
• Protein,
carbohydrate,
and fat
metabolism
Broccoli
Fruits
Grape and orange
juices
Meats
Spices (garlic and
basil)
Turkey
Whole grains
35 mcg
Copper • Antioxidant
• Bone formation
• Collagen and
connective
tissue formation
• Energy
production
• Iron metabolism
• Nervous system
function
Chocolate and
cocoa
Crustaceans and
shellfish
Lentils
Nuts and seeds
Organ meats
Whole grains
0.9 mg
Iodine • Growth and
development
• Metabolism
• Reproduction
• Thyroid hormone
production
Breads and cereals
Dairy products
Iodized salt
Potatoes
Seafood
Seaweed
Turkey
150 mcg
Iron • Energy
production
• Growth and
development
• Immune function
• Red blood cell
formation
• Reproduction
• Wound healing
Beans and peas
Dark-green
vegetables
Meats
Poultry
Prunes and prune
juice
Raisins
Seafood
Whole-grain,
enriched, and
fortified cereals
and breads
18 mg
Table 15.3 RDA for Minerals (CONT)
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MINERAL PURPOSE FOODS DV
Magnesium • Blood pressure
regulation
• Blood sugar
regulation
• Bone formation
• Energy
production
• Hormone
secretion
• Immune function
• Muscle
contraction
• Nervous system
function
• Normal heart
rhythm
• Protein formation
Avocados
Bananas
Beans and peas
Dairy products
Green leafy
vegetables
Nuts and pumpkin
seeds
Potatoes
Raisins
Wheat bran
Whole grains
420 mg
Manganese • Carbohydrate,
protein, and
cholesterol
metabolism
• Cartilage and
bone formation
• Wound healing
Beans
Nuts
Pineapple
Spinach
Sweet potato
Whole grains
2.3 mg
Molybdenum • Enzyme
production
Beans and peas
Nuts
Whole grains 45 mcg
Table 15.3 RDA for Minerals (CONT)
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CHAPTER 15 | Supplementation
MINERAL PURPOSE FOODS DV
Phosphorus • Acid-base
balance
• Bone formation
• Energy
production and
storage
• Hormone
activation
Beans and peas
Dairy products
Meats
Nuts and seeds
Poultry
Seafood
Whole-grain,
enriched, and
fortified cereals
and breads
1,2500 mg
Potassium • Blood pressure
regulation
• Carbohydrate
metabolism
• Fluid balance
• Growth and
development
• Heart function
• Muscle
contraction
• Nervous system
function
• Protein formation
Bananas
Beet greens
Juices
Milk
Oranges and orange
juice
Potatoes and sweet
potatoes
Prunes and prune
juice
Spinach
Tomatoes and
tomato products
White beans
Yogurt
4,700 mg
Selenium • Antioxidant
• Immune function
• Reproduction
• Thyroid function
Eggs
Enriched pasta and
rice
Meats
Nuts
Poultry
Seafood
Whole grains
55 mcg
Table 15.3 RDA for Minerals (CONT)
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MINERAL PURPOSE FOODS DV
Sodium • Acid-base
balance
• Blood pressure
regulation
• Fluid balance
• Muscle
contraction
• Nervous system
function
Breads and rolls
Cheese
Cold cuts and cured
meats
Mixed meat dishes
Mixed pasta dishes
Pizza
Poultry
Sandwiches
Savory snacks
Soups
Table salt
2,300 mg
Zinc • Growth and
development
• Immune function
• Nervous system
function
• Protein formation
• Reproduction
• Taste and smell
• Wound healing
Beans and peas
Beef
Dairy products
Fortified cereals
Nuts
Poultry
Seafood
Whole grains
11 mg
Note: mcg = microgram; mg = milligram (adapted from FDA fact sheet)
NUTRIENT ABSORPTION
It is critical for a fitness professional to understand the role the digestive system plays
in nutrient absorption, especially for vitamins and minerals. The gastrointestinal (GI) tract
coordinates and controls the absorption sites for nutrients and helps remove toxins. An
individual with a fully functioning GI tract may absorb more than 95 percent of the food
consumed. Dietary ingredients including vitamins and minerals are absorbed by the cells
lining the inside of the digestive tract and are used for metabolic processes. The pathways
of metabolism depend on nutrients that are broken down to produce energy, which helps the
body build new cells and protein.
Table 15.3 RDA for Minerals (CONT)
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CHAPTER 15 | Supplementation
Organs such as the esophagus, stomach, and intestines work together to mechanically break
down and digest food in the body. The absorption site of nutrients depends on the type
of dietary ingredient. The duodenum is the first part of the small intestine leading to the
jejunum, which makes up the middle part of the small intestine. This site is responsible
for breaking down and absorbing nutrients, though some nutrients will be absorbed before
reaching the small intestine or after in the ileum.
Water, sodium,
potassium, vitamin K
Fundus
Antrum
Bile
Ileocecal valve
Cecum
Ascending colon
Pylorus
Pancreatic
enzymes
Water
and sodium
Monosaccharides
Disaccharides
Amino
acids and
simple
peptides
Bile salts
Water-soluble
vitamins
Vitamin B12
Esophagus
PRINCIPAL ABSORPTION SITES FOR NUTRIENTS
Duodenum
Jejunum
Ileum
Stomach
Body
Minerals
Fatty acids, mono Vitamins A&D
and diglycerides
Figure 15.1 Principal Absorption Sites for Nutrients
SUPPLEMENTATION AND LIFE STAGES
All stages of life are unique and affect health and disease risk differently. Various guidelines
offer specific recommendations for all life stages, including infants, toddlers, and pregnant
and lactating women. Dietary guidelines from around the world can be found through the
USDA’s National Agricultural Library, which provides information on the nutrient needs
necessary to support healthy dietary patterns for people in specific countries. Vitamin and
mineral needs vary during each stage of life. Formulations should address common
deficiencies without going over the Upper Limit (UL) suggested for each nutrient.
UPPER LIMIT (UL):
The highest level of nutrient
intake that is likely to pose
no risk of adverse effects
for almost all individuals in
the general population.
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Some MVMs are made to supplement the general population while others are formulated to
meet specific needs. A great example of this is iron and folate intake needing to be higher for
menstruating women than for men of the same age. The daily recommendations for vitamins
A, B, E, and K and the mineral zinc are based on body size, and since men are typically larger,
they generally need to intake more than women.
A man’s MVM supplement might contain extra lycopene, which has been shown to protect
against prostate cancer. When choosing an MVM supplement, it is important to find the
appropriate one based on sex and age. Children’s vitamins are often made in a chewable
form. They are made with fewer amounts of certain vitamins and minerals because some
vitamins and minerals such as iron may be toxic to children at certain levels. However, for
seniors, nutrients such as vitamins B12 and D are needed in larger quantities and become
more prevalent in MVM supplements.
Ages 4–13
Nutritional requirements for children are higher than those for adults in proportion to body
weight. Rapid growth and development make proper nutrition critical at this age. Unfortunately,
intake recommendations are not based on data specific to children. Instead, adult intake
values are reduced using a mathematical formula that accounts for metabolic body weight
and growth.
Ages 13–18
During puberty, physical changes occur that affect males and females differently. Starting as
young as 10 years of age and going up to 16 years, growth and cognitive development occur,
which require adequate nutrient intake. The period that follows the onset of puberty and
develops a child into an adult is called adolescence. Micronutrient intake during adolescence
decreases in comparison to childhood, with childhood being the period that starts at two
years of age and stops at adolescence. For example, the DV for vitamin A is higher during
childhood. Some adolescents may also require combined calcium-magnesium supplements
if dietary intake is not enough. In addition, many adolescents use sunscreen while outdoors;
therefore, a vitamin D supplement may also be required.
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CHAPTER 15 | Supplementation
Prenatal, Pregnant, and Breastfeeding
Proper nutrition is important all the time and even more important during pregnancy because
the food women consume is also the main source of nutrients for the baby. It is crucial that
women obtain adequate amounts of iron, folate, calcium, vitamin D, and protein. Maternal
malnutrition may cause neural tube defects, premature birth, or low birth weight. Additionally,
there is an increased risk of anemia as a woman’s body attempts to increase her blood
supply for her baby. Becoming severely anemic during pregnancy has been associated with an
increased mortality rate during labor. Nutrient intake from a nutrition plan and supplements
should ultimately support the mother and growing fetus. A woman’s gynecologist should
provide specific recommendations based on her individual needs.
Micronutrient intake is generally higher for lactating mothers than pregnant women. Exceptions
to this are iron, folate, and calcium, which should be reduced during breastfeeding. Lactating
women who meet the RDA for energy are likely to meet the RDA for all nutrients. To maintain
health, lactating women should follow a nutrition plan consisting of nutrient-rich foods.
Elderly
Beginning at the age of 65, metabolism slows down, and nutrient intake requirements
change. Folate intake should increase to help reduce homocysteine (an amino acid) levels in
the blood. Vitamins B6 and B12 and folate break down homocysteine to create other
chemicals the body needs. High homocysteine levels may indicate a vitamin deficiency.
Without treatment, elevated homocysteine increases the risks for dementia, heart disease,
and stroke. Increasing riboflavin intake may help prevent the development of age-related
cataracts, a clouding in the lens of an eye and reduce the risk of fracture in women. Aging
also reduces the capacity for the body to synthesize vitamin D in the skin. Therefore, the
Linus Pauling Institute recommends a daily intake of 2,000 international units (IU) of vitamin
D. In addition, calcium intake minimizes bone loss and should be at 1,000–1,200 milligrams
(mg) per day. Intrinsic factor (IF), necessary for vitamin B12 absorption in the gut, activity
also tends to decrease.
MEAL REPLACEMENTS
Meal replacements are generally a prepackaged drink, bar, or powder used to replace a
meal. The addition of vitamins and minerals in meal replacements makes them a convenient
supplement for many individuals. Meal replacements may be popular in weight-loss programs,
low-calorie diets, and even in medical weight-loss programs. Research on meal replacements
INTERNATIONAL UNITS
(IU):
The quantity of a substance
that has a biological effect.
Amount varies depending
on the substance.
INTRINSIC FACTOR (IF):
A substance secreted by
the stomach that enables
the body to absorb vitamin
B12.
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proves that they work for weight loss. A meta-analysis of 30 weight-loss studies found that
meal replacements were as effective as traditional meal plans. Participants in these studies
often cited the convenience of meal replacements for weight-loss success. Nevertheless,
fitness professionals should consider what research studies have shown about meal
replacements before suggesting them.
Table 15.4 Meal Replacement Considerations and Research
MEAL REPLACEMENT CONSIDERATIONS AND RESEARCH
Program length
Meal replacements significantly increase weight loss during
the first four months of a program.
Supports prolonged weight loss
May be helpful for initial weight loss but not for long-term
maintenance
Shakes and liquids
Meal replacement shakes and drinks are often associated
with weight loss.
Intake with 388 Calories (Cal) in total energy at dinner time
alone contributed to improvement in body composition in men
and women who were overweight or obese.
Solid meal
replacements
Solid meal replacements may be better options for weight
loss.
May increase satiety and decrease hunger
May also increase program compliance over the long term
There are many factors that contribute to how much people consume and the number of
calories required. When nutrients are consumed in excess of calorie needs, these nutrients
are stored as body fat. Meal replacement shakes are often higher in vitamin, mineral, and
protein content, which can help those seeking lean mass gain. Understanding energy balance
is crucial to knowing when and how to implement meal replacement shakes as a supplement
to food.
PERFORMANCE SUPPLEMENTS
Fitness professionals want clients to feel, look, and perform their best. Supplementation
beyond a basic MVM aims to get the specific nutrients at the correct place and time to
SATIETY:
The feeling of fullness and
satisfaction.
ENERGY BALANCE:
The state achieved when
energy intake is equal to
energy expenditure.
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CHAPTER 15 | Supplementation
maximize performance and recovery. Creatine monohydrate (CM) taken pre-workout to
maximize high-intensity muscle contractions and strength is an example of this. There are
undoubtedly many more products and ingredients that prepare the body for exercise, impact
performance, and enhance recovery.
Performance supplements contain different ingredients, many of which are vitamins, minerals,
protein, creatine, and herbs. This category of supplements is intended to improve both activity
and recovery. It includes ergogenic aids, which are specifically taken to improve activity or
performance. The Office of Dietary Supplements lists the following ingredients as popular for
exercise and athletic performance with suggested ULs based on past research studies.
Table 15.5 Popular Fitness Supplements for Exercise and Athletic Performance
INGREDIENT
EFFECT ON EXERCISE AND
PERFORMANCE
SAFE GENERAL UL
Antioxidants (vitamin
C, vitamin E, and
coenzyme Q10)
Minimizes free radical damage to
skeletal muscle
Reduces muscle fatigue,
inflammation, and soreness
Vitamin C:
2,000 mg/day
Vitamin E:
1,000 mg/day
Coenzyme Q10: 120 mg
Arginine
Increases blood flow and delivery
of oxygen and nutrients to muscle
Increases secretion of human
growth hormone
Up to 9 g/day
Beta-alanine
Increases synthesis of carnosine,
a dipeptide that buffers changes
in muscle pH, reducing muscle
fatigue
1.6–6.4 g/day for up to
eight weeks
Nitrate (beetroot
extract)
Dilates blood vessels in exercising
muscle
Improves energy production
310–682 mg or 2 cups
of beetroot juice 2.5–3
hours before exercise
Branched-chain amino
acids (BCAAs): leucine,
isoleucine, and valine
Metabolized by mitochondria in
skeletal muscle to produce energy
during exercise
Up to 20 g/day in
divided doses
CREATINE
MONOHYDRATE (CM):
An organic compound that
increases phosphocreatine
levels and adenosine
triphosphate (ATP) energy
production leading to
enhanced strength and
power.
BRANCHED-CHAIN
AMINO ACIDS
(BCAAS):
A group of three essential
amino acids (leucine,
isoleucine, and valine) that
help the body build muscle
and decrease muscle
fatigue.
 ISSA | Certified Personal Trainer | 584
INGREDIENT
EFFECT ON EXERCISE AND
PERFORMANCE
SAFE GENERAL UL
Caffeine
Reduces perceived pain and
exertion and increases fat
metabolism
Up to 400–500 mg/day
for adults
Calcium Improves bone and joint health and
helps muscles contract Up to 2,500 mg/day
Citrulline Increases delivery of oxygen and
nutrients to muscle 6 g/day
Creatine Helps muscles generate energy for
short-term anaerobic activity
3–5 g/day for up to 12
weeks
Glutamine
Metabolism and energy production
Improves immune function and
preserves protein stores
Reduces fatigue and decreases
muscle soreness
0.42 g/kg of body weight
Iron
Increases oxygen uptake
Reduces heart rate and decreases
lactate concentration during
exercise, which in turn increases
blood flow
Up to 45 mg/day
Note: g = gram; kg = kilogram; mg = milligram.
See vitamin and mineral tables earlier in the chapter for reference
PROTEIN
Resistance and endurance exercise are recommended to build and maintain strength, maintain
and improve health and counteract the effects of aging. Stronger muscles contribute to a
more active lifestyle, which supports well-being and good health. Further, maintaining muscle
strength reduces the risk of chronic disease, functional limitations, and physical disability.
Even though resistance training may lessen the catabolic effects of aging, muscle strength
and metabolism still decline with age. Dietary protein supplementation counteracts these
effects by boosting protein anabolism, and such supplementation is essential to maintain
ANABOLISM:
The building of complex
molecules in the body
from more simple, smaller
molecules.
CATABOLIC:
Metabolic activity involving
the breakdown of molecules
such as proteins or lipids.
Table 15.5 Popular Fitness Supplements for Exercise and Athletic
Performance (CONT)
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CHAPTER 15 | Supplementation
strength and general health even at a young age. When a client fails to consume adequate
amounts of dietary protein, supplements can help make up for the deficiency. In addition, low-fat
and low-calorie protein sources may be an ideal weight-loss solution for some because they
provide an essential nutrient in a convenient form.
Protein Quality Scoring
To understand the rating scales used to classify proteins, a fitness professional should first
consider what protein is needed for. Protein is made up of amino acids, with some of them
being essential (the body cannot create them) and needing to be consumed from an outside
source. Others are nonessential, and the body can manufacture them internally from other
sources. Dietary protein must be consumed to get these essential amino acids (EAAs),
and certain protein sources are better able to meet the EAA needs of the human body than
others.
As such, a way of “scoring” a dietary protein source on its ability to meet these essential
needs was created. The higher the score, the higher the content of EAAs, and the better this
food source could sustain all of protein’s various functions in the body. However, it is important
for a fitness professional to understand that once EAA needs are met, ingesting more of
them will not cause greater muscle protein synthesis (MPS). Higher-rated proteins can
simply meet the needs of the body with less total protein. In contrast, eating lower-rated
proteins will raise a client’s total protein intake needs. In addition, the biological value (BV)
of a protein measures the proportion of absorbed protein from a food that is incorporated
into the proteins of the human body. The BV is measured in percentage values and expresses
how readily the digested protein can be used in protein synthesis, which is also known as
bioavailability.
The protein digestibility-corrected amino acid score (PDCAAS) measures the bioavailability
of a protein and its amino acid profile. PDCAASs range from 0 to 1.00, but some proteins,
such as whey protein isolate, can have a score higher than 1.00. This method was adopted
in 2003 with some criticism, for example, about where the nitrogen was measured and the
target research group of preschool-age children.
The latest measure of protein quality is the digestible indispensable amino acid score (DIAAS).
Adopted in 2013, it also measures bioavailability and amino acid profile. The difference is that
the PDCAAS measures how much protein is absorbed after it leaves the small intestine. These
scores offer valuable insights when deciding which protein is right for a client.
MUSCLE PROTEIN
SYNTHESIS (MPS):
A process that produces
protein to repair muscle
damage and oppose
muscle breakdown.
BIOLOGICAL VALUE
(BV):
The percentage of protein
used by the body.
BIOAVAILABILITY:
The amount of a substance
that enters the circulation
when introduced into the
body and is effective.
PROTEIN
DIGESTIBILITYCORRECTED AMINO
ACID SCORE
(PDCAAS):
Measures the nutritional
quality of protein.
DIGESTIBLE
INDISPENSABLE
AMINO ACID SCORE
(DIAAS):
Measures the amount of
amino acids absorbed by
the body.
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PROTEIN SOURCES
Meat, poultry, seafood, beans, peas, eggs, and nuts are protein sources. The amount of
protein a client needs depends on many factors including age, sex, and level of physical
activity. Those who are more physically active need extra protein for muscle repair and growth.
It is important to consider the quality of protein and to choose a variety of foods to improve
the health benefits of protein.
Plant-Based Protein
Vegetarian and vegan nutrition plans may lead to insufficient protein intake because plantbased proteins naturally contain less amounts of total protein compared to animal-based
protein sources. Vegetarians must consume a variety of plant-based foods to obtain the
required amount of amino acids. These foods include legumes, soy products, grains, nuts,
and seeds. Additionally, consuming more plant-based protein instead of animal-based protein
has been shown to contribute to a reduced risk of chronic diseases.
TEST TIP!
Examples of high-protein plant-based foods include:
Legumes
Nuts
Seeds
Soy
Hemp
Many plant-based protein sources are incomplete proteins and do not contain all the EAAs
the body needs to build cells. Soy, chickpea, rice, spirulina, quinoa, oat, and hemp seed
protein are popular alternatives to animal-based proteins. However, sometimes to make a
complete protein, two foods need to be combined and consumed together. Examples of
complete protein combinations include whole wheat toast and peanut butter, beans and rice,
and pita chips and hummus.
COMPLETE PROTEIN:
A food source containing all
nine essential amino acids
the body needs.
INCOMPLETE
PROTEINS:
A food source that lacks
one or more of the nine
essential amino acids.
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CHAPTER 15 | Supplementation
Table 15.6 BV and PDCAAS of Plant-Based Protein
BV AND PDCAAS OF COMMON PLANT-BASED PROTEIN
Protein Source BV PDCAAS
Soy protein isolate 94 1.00
Chickpeas 53 0.78
Rice 83 0.47
Spirulina 95 1.00
Quinoa 83 0.79
Oats 86 0.59
Hemp seed 86 0.52
Animal-Based Protein
Animal proteins such as meat, eggs, and milk are complete proteins. They contain all the
EAAs the body needs. Other animal-based protein sources are fish, chicken, cheese, bison,
and turkey. These high-quality protein sources contain adequate amounts of vitamin B12,
vitamin D, and zinc, which are all found in larger quantities in animal-based proteins compared
to plant-based ones.
Red meat is also a great source of protein and contains vitamins and minerals essential
to health. For example, red meat contains enough iron to help make DNA and keep red
blood cells healthy. However, there are studies showing that increasingly eating red meat,
particularly processed meat, over a long period of time is linked to an increased risk of
disease and mortality. For this reason, it is important for a client to focus on eating a variety
of animal proteins and to limit unprocessed red meat consumption.
Milk-Based Protein
Whey and casein are two proteins that come from milk, and both contain all nine EAAs. In
milk, casein are the curds, and whey is the liquid. When being processed into a powder,
casein and whey are separated from each other. Whey contains a large amount of the amino
acid L-cysteine and is one of the primary proteins found in dairy products. It also provides a
large amount of EAAs needed for body function. On the other hand, casein is digested more
slowly than whey, which means it releases amino acids gradually and is anticatabolic. This
ANTICATABOLIC:
Properties that protect
muscle mass from being
broken down.
 ISSA | Certified Personal Trainer | 588
helps reduce muscle breakdown in circumstances where a client may go a long period of time
without eating. Casein is often consumed prior to sleep because this is generally a long
fasting period.
Table 15.7 BV and PDCAAS of Animal-Based Protein
BV AND PDCAAS OF COMMON ANIMAL-BASED PROTEIN
Protein Source BV PDCAAS
Whey protein isolate 104 1.00
Casein isolate 77 0.78
Fish 76 0.90
Chicken 79 0.95
Beef 80 0.92
Protein Timing
Protein timing is a controversial approach used to optimize training effects, such as muscle
growth and strength gains. It is based on the idea of consuming protein as close to a training
session as possible. This includes before, during, and after exercise.
The general train of thought is that after exercise there is a limited time window during which
protein is needed to increase protein synthesis. A refractory period follows this short window,
and it can take a few hours before a spike in MPS can occur again. So, it may be beneficial
to consume a protein supplement before the refractory period.
A fast-acting protein such as whey that consists of leucine promotes optimal MPS. However,
insulin is needed for protein and leucine to be effective, which is why a carbohydrate source paired
with protein following a workout is more effective. Some studies report that this combination
results in a larger increase of lean body mass compared to just a protein source alone.
Variables that a fitness professional should consider for total protein needs are a client’s age,
weight, caloric intake, activity level, and goals. The current RDA for healthy individuals is 0.8 grams
(g)/kilogram (kg)/day, and for more active individuals, 1.4–1.6 g/kg/day is appropriate. Claims of
increased muscle mass, increased fat loss, improved performance, and greater recovery influence
the popularity of protein supplements. Consuming such high amounts of protein can be achieved
more comfortably through protein supplements and may help clients reach the RDA.
REFRACTORY PERIOD:
A window where muscle
protein synthesis (MPS)
becomes resistant and
amino acids are used for
other processes.
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CHAPTER 15 | Supplementation
GLUTAMINE
Glutamine is a conditionally dispensable amino acid found in dietary proteins and made by
the body. It is not an EAA except in times of illness or stress. This is why glutamine plays a
critical role in immune system function and gut health. It is produced naturally in the body,
but supplementation may be beneficial when levels are low. When the body is under excess
stress, such as during injury or illness, glutamine levels decrease. As a precursor for protein,
glutamine supplementation plays a role in metabolism, nitrogen balance, and protein
synthesis. These growth factors involve cell proliferation, which leads to an increase in cell
number and assists with tissue growth.
Glutamine has anticatabolic effects, reduces cortisol levels, and elevates growth hormone
levels. In research studies, glutamine has been shown to be effective in dosages of 2 to
5 g per day. Athletes have been known to consume up to 10 g per day. However, more
current research is needed to establish and confirm any associated benefits. The benefits
are interesting for athletes who engage in prolonged exercise, but beside minimal fatigue
markers, glutamine supplementation seems to have little effect on physical performance.
Another study examined the effects of 30 g of glutamine in type 2 diabetes patients and
showed a significant difference in reduced waist circumference and increased fat-free mass. It
is important for a fitness professional to remember that glutamine is often combined with other
dietary ingredients and ergogenic aids, so the benefits cannot be attributed to just glutamine.
Glutamine is the body’s most abundant free amino acid. It is produced in the muscles and
distributed by the blood to the tissues. During times of stress, the body may use more
glutamine than the muscles can replenish, and muscle wasting can occur. After surgery or
traumatic injury, protein, specifically nitrogen, is necessary to repair wounds and keep the
vital organs functioning. About one-third of this nitrogen comes from glutamine.
OMEGA-3 FATTY ACIDS
Next to an MVM formula, omega-3 supplements are likely the second most commonly known
supplement for consumers. Just as there are EAAs in protein, there are essential fatty acids
in dietary fat. Fats are necessary in a nutrition plan for cellular health, but the typical American
nutrition plan has an unfavorable ratio of omega-6 to omega-3 fatty acids. Simply put, omega-6
fatty acids tend to be pro-inflammatory, while omega-3 fatty acids tend to be anti-inflammatory.
CELL PROLIFERATION:
The process by which a
cell grows and divides to
produce new cells.
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The ratio of omega-6 to omega-3 fatty acids in typical Western diets is approximately 16:1,
with most of those omega-6 fatty acids coming from vegetable oils. This includes sunflower
oil, soybean oil, corn oil, cottonseed oil, and any processed foods that contain them. An
ideal ratio would be 4:1. Fatty and oily fish are known to be the best dietary sources of
omega-3 fatty acids, but many Americans do not consume enough of them. That is why
omega-3 supplementation is highly recommended by most health and regulatory agencies
and organizations worldwide.
Fish oil is a popular supplement taken to increase omega-3 intake, but increasing omega-3
intake to compensate for excess omega-6 fatty acids is not safe. It is crucial to decrease
omega-6 fatty acids when the ratio of omega-6 to omega-3 fatty acids is extremely high. A
ratio that is too high may contribute to increased inflammation in the body and is caused by
consuming too much seed and vegetable oils.
As with any nutrient, supplementation should be considered if a client is not intaking enough
through their nutrition plan. Dietary forms of omega-3 include fatty fish, nuts, seeds, and
some plants. Two servings of fatty fish a week provide beneficial levels of the essential
omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
As with all supplement use, it is best to look for a brand that is third-party validated for
content and certified to be free of mercury and other environmental contaminants. Mercury
is a well-known heavy metal and is linked to many degrees of toxicity. Fish contain mercury
due to industrial sources giving off hazardous air pollutants that fall to the ground and
contaminate the water. Since trace amounts of toxins remain in fish oil supplement products,
it is important to select a brand validated by a third party.
Plant-Based Alternatives
Although DHA and EPA are found mostly in seafood, they are essential nutrients for fish and
other sea creatures. Essential nutrients must be taken into the body from an outside source.
Fish get dietary DHA and EPA from algae and seaweed. This means that DHA and EPA are not
originally found in fish. Instead, fish absorb omega-3 by consuming algae.
Other plant-based sources of omega-3 are chia seeds, algal oil, hemp, walnuts, and flaxseeds.
Algal oil is a vegan alternative to fish oil that is high in both DHA and EPA. One study found algal
oil equal to cooked salmon in terms of omega-3 absorption. Omega-3 fatty acids are an essential
part of polyunsaturated fats and have been shown to prevent heart disease and stroke.
POLYUNSATURATED
FATS:
Fat molecules containing
more than one unsaturated
carbon bond, are liquid at
room temperature, and
solid when chilled.
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CHAPTER 15 | Supplementation
ERGOGENIC AIDS
An ergogenic aid is a nutritional, pharmacologic, physiologic, or psychologic aid that enhances
exercise capacity. Some techniques, such as carbo-loading, are safe and widely accepted. Others,
such as the use of anabolic-androgenic steroids (AAS), are banned by governing bodies. For this
discussion, a fitness professional should recognize that steroids are not dietary supplements.
Rather, they are drugs, and when used by healthy individuals with no physiological need other than
the desire to look, perform, or recover better, steroids are illegal.
As for dietary supplements as ergogenic aids, the American Academy of Pediatrics opposes their
use for young athletes. Allergic reactions and GI disorders may result from overusing supplements
and may increase the risk for obesity in children and adolescents when used excessively. When
and if applicable, a fitness professional should first discuss supplement recommendations with
a parent or guardian before making any recommendations to a child or minor. The Academy of
Nutrition and Dietetics, Dietitians of Canada, and American College of Sports Medicine published
their position statement on nutrition and athletic performance in 2016, stating,
Supplement use is best undertaken as an adjunct to a well-chosen nutrition plan. It is rarely
effective outside these conditions and not justified in the case of young athletes.
The effects of certain ergogenic aids must be carefully weighed before choosing to
supplement. In most cases, performance and other gains can be realized through proper
training and a well-balanced nutrition plan. Ergogenic supplement use will not make up for
a poor nutrition plan and training. However, all else being equal and correct, there are some
compounds that can be effective.
CREATINE
Creatine is one of the most researched and effective ergogenic supplements, with the
monohydrate form being the most studied form of creatine. The goal of supplementing with
CM is to increase intramuscular levels of creatine and speed the regeneration of creatine
phosphate (CP), which is expended during energy production. Similar in concept to the carboloading done by endurance athletes to increase glycogen stores, strength and power athletes
load creatine to increase CP levels, delaying its depletion and decreasing repletion time.
Activities dependent on CP as an energy source, including sprinting, resistance training, and
other sports requiring repetitive bursts of speed and power (football, baseball, rugby, hockey,
etc.), could also benefit from creatine supplementation. Creatine increases speed and energy
ANABOLICANDROGENIC
STEROIDS (AAS):
Synthetic variations of
the male sex hormone
testosterone.
 ISSA | Certified Personal Trainer | 592
in short bouts of high-intensity activities or sports, which leads to improved performance.
Since aerobic/endurance activity is not CP dependent, creatine supplementation does not
improve such activities.
Creatine may cause bloating and lead to water weight gain as a result of muscles retaining
more water. In fact, due to the supplement drawing water into the muscles and the potential
for weight gain associated with creatine-loading regimes, performance could theoretically be
impaired. It is inadvisable for beginning exercisers to supplement with creatine. The ability to
enhance muscle contractile strength and power relatively quickly can outpace the neurological
adaptations that allow an exerciser to control those gains, increasing the possibility of an
injury.
Women and men can expect the same types of responses to creatine supplementation. It
is best to prepare a client for the possibility of weight gain, specifically from water retention,
with this supplement. Creatine contains no calories and therefore has no impact on fat
metabolism. However, individual physical responses to creatine supplementation are common,
as with any supplement use. Creatine is an amino acid already naturally found in muscles,
which means some clients may have higher levels than others to begin with. Each individual
converts substances differently, and dietary intake can influence a client’s normal creatine
levels. Since dietary creatine is mostly obtained via animal muscle meats (beef, chicken,
etc.), those who do not consume these foods often or at all will respond more dramatically
to creatine supplementation.
BETA-ALANINE
Beta-alanine (BA) is a nonessential amino acid produced naturally in the body. It aids in the
production of other protein building blocks, such as carnosine, and plays a role in muscle
endurance during high-intensity exercise. BA supplementation has been shown to increase
skeletal muscle levels of carnosine, which is an intramuscular pH buffer and antioxidant.
Supplementing with BA can lower exercise-induced acidosis, potentially delaying fatigue and
improving performance. In addition, free radicals are produced at an accelerated rate during
exercise and are thought to contribute to exercise-induced damage and fatigue.
Supplementation with BA may reduce these negative effects in exercising muscles and help
maintain performance levels.
A systematic review of BA supplementation found moderate- to high-quality studies supporting
the findings that BA may increase power output and training capacity, decrease feelings
of fatigue and exhaustion, and have positive effects on body composition and carnosine
BETA-ALANINE (BA):
A nonessential amino acid
that is naturally produced
by the body.
ACIDOSIS:
When the kidneys and lungs
cannot keep the body’s pH
in balance due to excess
acid in body fluids.
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CHAPTER 15 | Supplementation
content. Carnosine is a protein building block that is naturally produced in the body and
mainly found in working muscles. In addition to muscle function, carnosine plays a role in
heart and brain function by preventing cell damage. Carnosine studies show intake ranges
of 4 to 6 g/day for at least two weeks to improve exercise performance. The most common
side effect noted in BA supplementation is paresthesia. This is a harmless side effect and
results in a numbness or tingling feeling in the face and neck.
Branched-Chain Amino Acids
Branched-chain amino acids (BCAAs) are a group of three EAAs including leucine, isoleucine,
and valine. Leucine is an essential BCAA, and EAA formulas have been shown to play a role
in MPS. Isoleucine and valine aid in muscle development, increase endurance, and promote
muscle recovery and repair.
These EAA formulas, and leucine itself, stimulate MPS via a regulatory “switch” called the
“mammalian target of rapamycin complex 1.” Studies have shown benefits such as increased
and more rapid recovery following exercise, increased MPS (especially in older and elderly
populations), decreased muscle protein breakdown, and reductions in muscle soreness.
The body uses amino acids to make proteins, which are the building blocks to cell, tissue,
and organ function. BCAAs play an important role in metabolism including muscle growth,
recovery, and repair while leucine and isoleucine specifically promote blood sugar control.
However, the body requires all the EAAs for optimal benefits such as reducing exercise fatigue
and improving energy metabolism.
STIMULANTS
Stimulants are often used in sports to enhance performance and by those seeking faster
weight loss. These substances speed up body systems and elevate alertness, mood, and
awareness. They can raise heart rate, temperature, blood sugar, and blood pressure; constrict
blood vessels; and open the pathways of the respiratory system. In addition, they can
decrease feelings of hunger or fatigue. Many stimulants can be addicting, but each has its
own unique effects. They are often found in supplements, as seen with caffeine in energy
drinks, which are often used to boost energy during workouts. Stimulants change the way the
brain works by altering how nerve cells communicate. For example, they can cause a buildup
of dopamine in the brain, making an individual feel intense pleasure and increased energy.
STIMULANTS:
A class of drugs that
temporarily improve
physical or mental function.
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Caffeine is a popular stimulant that shows some benefit during exercise through increases in
epinephrine. Epinephrine, also known as adrenaline, is a hormone produced by the adrenal
glands and helps break glycogen down into glucose for usable energy. It also significantly
increases power output for trained and sedentary clients. Research shows that caffeine may
have a greater effect on mood and reaction time in abstained caffeine consumers compared
to those who habitually consume caffeine.
Energy drinks often contain guarana, taurine, L-carnitine, and ginseng. Unfortunately, there
is not enough existing research on these ingredients to determine whether they have any
effect on energy separately or together. For example, L-carnitine may reduce fatigue for elderly
people with low muscular endurance. However, other research on L-carnitine has found no
influence on low-intensity, long-duration cardio exercise.
“Ginseng” is a general term that includes several different types of plants. Plants that fall
under the “ginseng” label include ashwagandha (Indian ginseng), Eleutherococcus senticosus
(Siberian ginseng), Eurycoma longifolia Jack (Malaysian ginseng), and many others. With such
a variety of ginseng options, it is difficult to know which kind is used in energy drinks and
what effects it might have.
BANNED SUBSTANCES
Some ergogenic aids have been banned for use by many organized sports organizations
to prevent unfair advantages. Once an athlete consumes and exceeds certain levels of
ergogenic aids, the side effects increase. Ergogenic aids are used to provide athletes with a
competitive advantage and must be monitored. Part of the reason for their ban is the fact that
they often have contaminants that can be harmful to health. They may also be listed as “not
for human consumption” in some cases. Some ergogenic aids are available for therapeutic
use monitored by a physician.
AAS are known for increasing muscle size and strength. A physician may prescribe steroids
to treat hormonal issues including low testosterone or disease-related muscle loss. However,
outside of a physician’s care, the use of steroids is inadvisable. A fitness professional should
remember that AAS are not dietary supplements but drugs, and as such AAS exceed a
personal trainer’s scope of practice.
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CHAPTER 15 | Supplementation
TEST TIP!
Negative Mental Health Effects of AAS
• Paranoid jealousy
• Extreme aggression
• Delusions
• Impaired judgment
• Mood swings
Physical Effects
• Increased risk of liver disease
• Increased risk of cardiovascular disease
• Hypertension
• Acne
• Baldness
Effects in Men
• Shrinking testicles
• Breast growth
• Reduced sperm count
• Impotence
• Reduced sex drive
• Increased risk of prostate cancer
Effects in Women
• Deep voice
• Growth of facial and body hair
• Abnormal menstruation
• Enlarged clitoris
• Decreased breast size
Effects in Teens
• Premature puberty
• Stunted growth (closure of growth plates)
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BOTANICAL SUPPLEMENTS
Botanical preparations are marketed in the US as dietary supplements and can include
nutrients such as herbs, enzymes, organ tissues, amino acids, and vitamins and minerals. A
botanical is a plant or plant part containing various medicinal properties. Due to their benefits
on health, they have become increasingly popular. A fitness professional should keep in mind
that they are not labeled as drugs but rather as dietary supplements because, by law, the
manufacturers of supplements cannot claim their products treat or prevent any disease.
Botanical supplements are used to maintain or improve health by supplementing a nutrition
plan with various health benefits. They come in many forms including fresh and dried
plants, plant parts, and extracts. The safety of botanicals is determined by the makeup of
the supplement, how the body responds to it, and the amount or dosage consumed. Each
botanical is consumed for different reasons ranging from fat loss to immune system function,
better sleep, and reduced anxiety. The following botanicals were selected for their popularity
and prevalence in the health and fitness industry.
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CHAPTER 15 | Supplementation
Table 15.8 Botanical Supplements
BOTANICAL PRIMARY USAGE RESEARCH NOTES
Cannabidiol
(CBD)
Reduce anxiety,
improve sleep, and
increase weight loss
Most research is done
on mice, not humans.
Results are inconclusive.
Dosages vary
depending on form
and use.
Cinnamon
Lower blood sugar
by increasing insulin
sensitivity
Proven effective as an
antidiabetic compound
and may reduce
cholesterol
Taking 2 g/day shows
anti-inflammatory
properties and lower
blood sugar levels.
Echinacea
Build up the immune
system and protect
against allergies
Results vary but show
a reduction in length
of sickness with
supplementation.
No optimal dose or
type
Garlic
Antioxidant and
anti-inflammatory
properties that protect
against allergies and
build immunity
Consistent findings
for increasing HDL
and decreasing LDL
by 10–15 percent
reduces blood pressure
and frequency of the
common cold.
Can be supplemented
via a nutrition plan or
aged garlic capsules.
Taking 300 mg/day
has been shown to
manage hypertension.
Ginger
Improve the movement
of food in the stomach
for gut health and
increase testosterone
No research regarding
gut health, increase in
testosterone found in
infertile men
May increase HDL
and decrease LDL.
Reduces inflammatory
markers. Comes in
forms such as fresh
or dried roots, tablets,
and liquid extract.
Green tea
Increase
norepinephrine and
induce fat loss
Fat loss effect is minor
and unreliable
May reduce LDL, lower
fasting blood glucose,
increase oxygen
uptake, and reduce
muscles soreness
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BOTANICAL PRIMARY USAGE RESEARCH NOTES
Hoodia Increase fat loss
Does not suppress
appetite, may increase
blood pressure and
heart rate
Has a desired effect
on appetite and weight
loss. Little available
research in humans.
Milk thistle
Promote cell repair
for liver health and
detoxification
No research to support
claims
May reduce acne
lesions with direct
application to the skin
Saw palmetto
Increase testosterone
levels and improve
prostate health
Not effective at
increasing testosterone
or suppressing prostate
growth
Mixed and
inconsistent findings
regarding sexual
function
Valerian Improve sleep and
reduce anxiety
Research points to no
effect.
May reduce menstrual
pain and symptoms of
PMS. Commonly used
before bedtime.
Note: g = gram; HDL = high-density lipoprotein; LDL = low-density lipoprotein; mg = millig