Dietary Changes, Fluid Replacement, Food Supplements and Drugs : Demonstration of Ergogenic Action and Potential Health Risks

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Guidelines of the Brazilian Society of Sports Medicine
Dietary changes, fluid replacement, food supplements and drugs:
demonstration of ergogenic action and potential health risks
Editor: Tales de Carvalho
Co-editors: Tânia Rodrigues, Flávia Meyer, Antonio Herbert Lancha Jr. and Eduardo Henrique De Rose
Participants: Antonio Claudio Lucas da Nóbrega, Arthur Haddad Herdy, Carlos Alberto Werutski,
Eney de Oliveira Fernandes, Félix Albuquerque Drummond, Glaycon Michels, Ileana Kazapi,
Kharla Medeiros, José Kawazoe Lazzolli, Luis Fernando Funchal, Luiz Aragon, Magnus Benetti,
Marcelo Bichels Leitão, Marcelo Salazar, Marcos Aurélio de Oliveira Brazão, Michel Dacar,
Rafael de Souza Trindade, Ricardo Nahas and Turíbio Leite de Barros Neto
Realization: Brazilian Society of Sports Medicine
Supported by: Gatorade Sports Science Institute (GSSI)
only an anti-ethical, but even a criminal situation. If it is
proven the prescription was deliberate, professional who
In Brazil, the indiscriminate use of different drugs, for
did it can be legally punished by a court of law.
both ergogenic and aesthetic purposes, has attracted atten-
Another aspect that justifies this consensus document is
tion and caused concern. Such use is being increasingly
the existence of cases in which there are flaws in meals
spread in environments where physical exercises are prac-
and fluid replacement schemes that restrain sports perfor-
ticed, especially gym academies and sports associations.
mance and place the health of physical exercise practitio-
Most of the times, it comes from an illegal trade, with
ners at risk, even of death. Such is the case of dehydration,
no control from sanitary surveillance departments, carried
often seen in long-course athletic contests.
out in the physical exercise practice facilities, and with di-
This consensus document had the input of eminent pro-
rect or indirect involvement of the professional in charge
fessionals and researchers of sports medicine and other
of the physical exercise sessions. Typically, under these
sports sciences in Brazil, and its main purpose is to add to
circumstances, there is no prescription from a specialist
an education process, by conveying information that may
physician and/or guidance from a sports science-trained
be used as guidelines for professionals who work in the
dietitian, who are the qualified professionals to act in such
field of sports and act on physical exercises program for
context. What should be considered only for specific cir-
the overall population. This information is intended to reach
cumstances, and always under control of qualified profes-
the main stakeholders, who are the physical exercise prac-
sionals, tends to be used by individuals, with no indication
titioners, whether they are competitive athletes or anony-
whatsoever. The financial interest prevails on the well-be-
mous members of gym academies or other places where
ing and health of the population. And even when there is
sports are practiced, to preserve their health by making them
the involvement of physicians and dietitians, many a time
less vulnerable to nefarious actions from unqualified and/
the recommendation for use of products is made empiri-
or ill-will individuals. Ultimately, its purpose is to demys-
cally, with no specific knowledge nor scientific grounds to
tify improper attitudes that, in spite of lack of scientific
support it.
grounds and with potential health risk, are quite common
This is due, in part, because of the lack of knowledge
in the physical exercise practice environment. It aims to
that a balanced, quality meal, except for special circum-
disseminate the use of proven healthy practices, to allow
stances, meets the nutritional needs of a physical exercise
for the best sports performance.
practitioner, even a competition athlete, making unneces-
sary the use of food supplements.
When one deals with the use of some drugs and hor-
Prof. Dr. Tales de Carvalho
mones of proven ergonogenic effect, but that poses health
Editor of the Guidelines
hazards and are considered doping substances, he faces not
President, Brazilian Society of Sports Medicine
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

For the stands taken by this document, the adopted cri-
from an ordinary meal. One can state that the athlete who
teria were suggested by the Evidence-Based Cardiology
wishes to optimize his/her performance, before any nutri-
Committee of the Brazilian Cardiology Society and Bra-
tional manipulation should follow a diet that is appropriate
zilian Medical Association (tables 1 e 2). The stands were
to his/her endured effort in terms of quantity and variety,
classified according to the status of recommendation and
taking into consideration what has been established as a
the level of scientific evidence. To determine the status of
healthy food.
the recommendation, in addition to the degree of scientific
The guidelines in this section target healthy athletes,
evidence, the recommendation’s applicability, cost-bene-
adults and adolescents at the end stage of sexual matura-
fit and cost-effectiveness ratios, among other aspects, were
tion. They do not focus individuals who practice physi-
taken into consideration.
cal exercises with no further concern about perfor-
mance, for whom a balanced diet according to the

recommendations given to the overall population is
Scientific studies have proved that performance and
enough to maintain health and enable a good physical
health of athletes may benefit from dietary changes. There
performance. (Recommendation status A and evidence
are few controversies on this issue, due to documentation
degree 2).
that demonstrates beneficial effects to health, favorable
changes of body composition and enhanced athletic per-
Nutritional assessment
formance from dietary management. Studies have been
Nutritional assessment is an important factor for diet
according in reaching the conclusion that, in general, di-
design and compliance. A careful dietary anamnesis allows
etary management alone is enough to reach the above men-
the definition of strategies for the introduction of eventual
tioned outcomes. Food supplement should therefore be left
dietary changes that may be needed. Athletes should not
for special cases only, and its use should derive from pre-
be deprived of their favorite food, or start a diet with rules
scription of qualified professionals, dietitians and special-
and impositions divorced from their reality. Prescriptions
ist physicians.
should be flexible, so they can become a regular eating
The food and nutritional supplies industry has developed
habit. Nutritional needs can be calculated through appro-
modified food, aiming performance improvement. Typical-
priate protocols, being determined by specific tables. One
ly, they use only nutrients whose sources are in the food
should consider the modality of sports being practiced, the
training stage, the calendar of competitions and the pur-
poses of the technical team concerning performance, data
Degree of evidence
Degree 1: evidence based in a number of randomized, con-
Recommendation status
trolled, broad, concord, statistically appropriate trials, prefer-
ably with conclusive systematic reviews.
A = Always use. This is a conclusive recommendation, unani-
Degree 2: evidence based in few randomized, controlled, av-
mously adopted; conclusively useful and safe procedure;
erage-size trials or meta-analyses of many of such small or
proven effectiveness and safety. It almost always requires
average-size trials.
evidence level 1 or 2 for such recommendation status to be
Degree 3: evidence based in few high-quality randomized, con-
trolled trials.
B = Use is generally advised. The recommendation is consid-
Degree 4: evidence based in more than one high-quality co-
ered acceptable, but with remarks; acceptable and safe pro-
hort trials.
cedure; high potential for usefulness, but no conclusive proof,
Degree 5: evidence based in more than one quality case-con-
with a less solid degree of evidence.
trol study.
C = Use is upon personal decision. Undefined recommenda-
Degree 6: evidence based in more than one high-quality se-
tion; procedure about which there is no evidence for or against
ries of cases, including records.
its effectiveness and safety.
Degree 7: evidence based just in inferences from results
D = Use is generally not advised. Procedure not recom-
collected for other purposes (to test other hypothesis);
mended, even though it might be used in some exceptional
rational suppositions, animal-model experiments or experi-
instances, but it is a very poor option; minimal evidences of
ments based on mechanistic pathophysiology models and/
effectiveness and safety, but with some potential use in se-
or mechanisms of action; old procedure based on common
lected cases.
practice; opinions with no reference to prior studies.
E = Never use. Use is unanimously not recommended.
Source: Evidence-Based Cardiology Committee of the Brazilian Cardiology Society
Source: Evidence-Based Cardiology Committee of the Brazilian Cardiology Society
and Brazilian Medical Association.
and Brazilian Medical Association.
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

related to basal metabolism, energetic requirements for
lar mass, hormonal dysfunction, osteopenia, and higher
training, needs for body composition changes, and the pres-
incidence of chronic fatigue, musculoskeletal lesions, and
ence of clinical factors such as chewing, digestion and ab-
infectious disease, which are some of the main features of
sorption conditions. Energetic requirements are calculated
by the sum of basal energetic need (protocol of free choice),
When one wishes to change body composition by re-
mean energetic expenditure in training, and extra or re-
ducing the mass of fat, one typically suggests reducing
duced intake to control body composition.
caloric intake by selecting low-energetic density, low-fat
To determine the needs of macronutrients (carbohydrate,
foods. However, in athletes, a 10% to 20% reduction in
proteines and lipids), one should take into consideration
total caloric intake leads to changes in body composition
the caloric needs and the necessary digestion time for mus-
by reducing body fat, and not inducing to hunger or fa-
cle utilization. Macronutrients are essential for muscular
tigue, as diets of very low-calorie intake and low fat. A
recovery, maintenance of immunologic system, balance of
dramatic reduction in fat from diet may not ensure reduc-
the endocrine system, and maintenance and/or enhance-
tion in body fat, and cause significant muscular losses due
ment of performance.
to lack of important nutrients for post-exercise recovery,
Overall, micronutrients (vitamins, minerals and oligo-
such as liposoluble vitamins and proteins.
elements) present in balanced and diversified diets, with
In accordance with population nutritional recommen-
enough caloric intake to meet energetic demand, are enough
dations (RDI – National Research Council – 98), one
for the needs of a sportsperson. The use of food supple-
should intake, in Kilocalories (Kcal), from 1.5 to 1.7
ment is recommended in some special cases. One is the
times the produced energy, or from 37 to 41 Kcal/weight
use of folic acid by pregnant women, the use of calcium in
(Kg)/day. This variation is influenced by genetics, gen-
case of osteopenia and osteoporosis, and iron for anemia.
der, age, body weight, body composition, physical fit-
Micronutrients play an important role in energy produc-
ness, and training stage. One should take into consider-
tion, hemoglobine synthesis, bone health maintenance, im-
ation the frequency, intensity and duration of physical
munologic function, and protection of body tissues from
exercise sessions. Depending on the purpose, the calor-
oxidative damages. They are necessary to build and main-
ic rate can present broader variations, with diets rang-
tain muscular tissues after the exercises. The training can
ing from 30 to 50 Kcal/ weight (Kg)/day. (Recommen-
increase or change the needs of vitamins and minerals. The
dation status A and evidence degree 2).
stress from the exercises may result in a biochemical mus-
cular adjustment that increase nutritional needs, with higher
b) Carbohydrates
use and/or loss of micronutrients. Dietary adjustment, in
Ergogenic effect of carbohydrate intake during exercis-
terms of macronutrients, to higher caloric need derived from
es has been consistently demonstrated in a number of ex-
sports activities, provides, at the same time, adjustment in
periments, many of which carried out at stages lasting for
the intake of micronutrients. Thus, it is suggested that
hours. It has been shown that prolonged exercises signifi-
nutritional recommendations for the overall population
cantly decreases the level of muscular glycogen, and one
be used, calculated for the intake of 1,000 Kcalories.
should be constantly concerned on replacing it. Neverthe-
Therefore, the increment in the supply of micronutri-
less, a low carbohydrate intake by athletes has been observed.
ents is proportional to the caloric increase of the diet,
The energy used during training and competitions de-
and nutritional balance is kept at appropriate levels.
pends on the intensity and duration of exercises, gender of
(Recommendation status A and evidence degree 2).
athletes and initial nutritional status. The higher the inten-
sity of exercises, the higher the role of carbohydrates as
energy suppliers. The role of fat can be important for the
a) Total food caloric rate
time the exercise lasts, becoming even more significant
A number of studies have shown low caloric intake and
while the activity lasts and remains an open aerobic activ-
nutritional unbalance in professional and/or amateur ath-
ity. However, the proportion of energy from fat tends to
letes. In spite of the proven effectiveness of carbohydrates
decrease when the intensity of the exercise is enhanced,
to recover muscular glucogen, elite athletes still resist in
requiring a higher role from carbohydrates. With the exer-
taking this nutrient. An adequate meal in terms of carbo-
cise lasting longer, the role of protein is enhanced, which
hydrate supply helps maintaining body weight and com-
helps serum glucose levels to be maintained, mainly through
position, maximizing results from training and contribut-
liver gluconeogenesis.
ing to health maintenance. A negative caloric balance, from
Selection of food to be source of carbohydrates and the
a lower intake of micronutrients, may cause loss of muscu-
preparation of the meal immediately before the sports event
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

should be according to individual gastrointestinal features
tween 1.4 and 1.8 g/weight (kg). (Recommendation sta-
of each athlete. The recommendation to fraction diet in three
tus A and evidence degree 2).
to five meals a day should take into consideration the nec-
essary digestion time for the pre-training or pre-competi-
d) Lipids
tion meal. The size of the meal and its components as to
An adult requires about 1 g of fat per kg of body
amounts of proteins and fibers may require over three hours
weight daily, which is about 25% to 30% of the total
for gastric emptying. If it is impossible for one to wait for
amount of calories (TAC). Essential fatty acids intake
over three hours for digestion, gastric discomfort may be
should be of 8 to 10 g/day. For athletes, it goes the same
prevented by intake of food poor in fibers and rich in car-
nutritional recommendations for the population in gen-
bohydrates. It is suggested food of light or liquid consis-
eral as to the proportion of essential fatty acids, which
tency, with an adequate amount of carbohydrates. Thus,
is 10% for the saturated, polyunsaturated and mono-
the last meal before training should have enough fluid to
unsaturated. (Recommendation status A and evidence
keep hydration, poor in fat and fibers to facilitate gastric
degree 2).
emptying, rich in carbohydrates to keep serum glucose lev-
Athletes should be oriented not to have a poor-fat diet
els and maximize glucogen supplies, with moderate
for a long time. When hypolipidic diet is necessary, there
amounts of proteins, and should be part of the athletes nu-
should be quotas as to total calorie intake, being of less
tritional habit.
than 8% for saturated, more than 8% for mono-insaturat-
It is estimated that carbohydrate intake correspond-
ed, and from 7 to 10% for polyunsaturated. It has been
ing to 60% to 70% of the daily calorie intake meets the
reported that, in general, athletes intake more then 30% of
demands of a sports training session. To optimize mus-
TAC in form of lipids, with deficit in the intake of carbohy-
cular recovery it is necessary carbohydrate intake of 5
drates, which are consumed in less than advisable propor-
to 8g/weight (kg)/day. In long-duration activities and/
or intense training, there is the need of up to 10g/weight
Some studies have suggested a positive effect of diets
(kg)/day for proper muscular glucogen recovery and/
somewhat rich in fat for athletic performance. Average-
or increase of muscular mass (Recommendation status
and long-chain lipid supplements have been suggested
A and evidence degree 2).
for intake a few hours before or during exercise. Thus,
The amount of used glucogen depends on the dura-
muscular glucogen would be spared. However, in face
tion of the exercise. For long contests, athletes should
of evidence available today, in this document we rec-
intake approximately 0.7 to 0.8 g/weight (kg) or between
ommend it should never be used. (Recommendation sta-
30 and 60 g of carbohydrate at each hour of exercise, to
tus E and evidence degree 7).
prevent hypoglycemia, glucogen depletion and fatigue.
Often the carbohydrates are part of beverages especially

e) Vitamins
developed for athletes. After an exhaustive exercise, it
There is disagreement as to greater needs by athletes.
is recommended intake of simple carbohydrate, in the
For athletes, it has been suggested the intake of C vita-
amount ranging from 0.7 to 1.5 g/weight (kg) within a
min between 500 and 1,500 mg/day, which would allow
four-hour period, which is enough for a full muscular
better immunologic response and important antioxidant
glucogen re-synthesis. (Recommendation status A and
action. It has also been suggested the use of vitamin E
evidence degree 2).
by athletes undergoing intense training, to enhance an-
tioxidant action. Scientific evidence allows physicians

c) Proteins
and nutritionists to prescribe C and E vitamins, even
For sedentary individuals, it is recommended a daily
with a low-degree evidence (Recommendation status C
intake (RDI) of proteins between 0.8 and 1.2 g/weight
and evidence degree 7).
(kg)/day. Individuals who practice physical exercises
require a higher amount, as proteins contribute to en-

f) Minerals
ergy supply in endurance exercises, and are necessary
Zinc plays a role in the cell respiratory process, and
in post-exercise muscular protein synthesis. For endur-
its shortage in athletes may cause anorexia, significant
ance athletes, proteins play an ancillary role in supply-
weight loss, fatigue, lower performance in endurance
ing energy to the activity, and one estimates its daily
competitions, and risk of osteoporosis, which explains
need to be between 1.2 and 1.6 g/weight (kg). For power
why it has been given as a supplement. However, due to
athletes, protein has an important role in supplying “raw
lack of quality scientific evidence on its systematic use
material” for tissue synthesis, being its daily need be-
as a nutritional supplement, this document recommends
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

it should not be used other than in regular meals. (Rec-
It is important for dehydration signs and symptoms to
ommendation status E and evidence degree 7).
be recognized. Mild to moderate dehydration is evidenced
Female athletes under low calorie diet may lack min-
by fatigue, loss of appetite and thirst, red skin, heat intol-
erals, particularly those involved in bone formation and
erance, dizziness, oliguria and enhanced urinary concen-
maintenance, such as calcium. Any diet should include,
tration. Severe dehydration causes difficulties to swallow,
at least, 1,000 mg/day of calcium. The low level of iron
loss of balance, dry and withered skin, sunken eyes and
seen in about 15% of the world population is cause of
blurred vision, dysuria, numbness, delusions, and muscle
fatigue and anemia. Iron deficiency affects performance
spasms. It has been shown that fluid intake, regardless of
and the immunologic system. Special attention should
the presence of carbohydrate, enhances performance dur-
be paid to the intake of high bioavailability food with
ing one hour of high-intensity aerobic exercise. As exer-
iron, being recommended for the female population the
cise-related dehydration may occur not only from intense
amount of 15 mg/day, and 10 mg/day for males. For
sweating, but also from insufficient intake and/or deficient
pregnant women, RDI is of 30 mg. These needs may be
absorption of fluids, it is important to recognize the ele-
achieved by manipulating diet, not being supplementation
ments that influence hydration quality.
necessary. For dietary manipulation, in the specified cas-
es, this document confers a high recommendation status.

(Recommendation status A and evidence degree 2).
Water can be a good rehydration option, as it is readily
available, inexpensive and allows a somewhat swift gastric
emptying. However, for prolonged activities, that last for
The stress of the exercise is accentuated by dehydration,
more than one hour, or for highly intense activities, such
which increases body temperature, impairs physiological
as football (soccer), basketball and tennis, it has the disad-
responses and physical performance, and causes health
vantage of not containing sodium or carbohydrates, and
hazards. These effects may take place even if dehydration
because it is tasteless, it favors involuntary dehydration and
is light or moderate, with up to 2% of loss, and worsens as
makes hydroelectrolyte balance process difficult. Volun-
it increases. With 1 to 2% dehydration, body temperature
tary dehydration is seen when one compares hydration with
starts raising in up to 0.4oC for each subsequent dehydra-
water versus hydration with flavored beverages.
tion proportion. At about 3% there is a significant perfor-
mance weakening; between 4 to 6%, thermal fatigue may
occur; from 6% on, there is the risk of thermal shock, coma
As we lose sodium through sweat, in some circumstanc-
and death.
es it should be taken during exercise. Sodium concentra-
As sweat is hypotonic in relation to blood, dehydration
tion in the sweat varies from one individual to another, in
from exercise may lead to an increase in serum osmolarity.
accordance to a number of factors such as age, the degree
Both hypovolemia and hyperosmolarity increase internal
of fitness and being used to a warm climate. Mean sodium
temperature and reduce heat dissipation from evaporation
concentration in the sweat for an adult in around 40 mEq/
and convection. Serum hyperosmolarity may increase in-
L. Assuming that a person of 70 kg runs for three hours
ternal temperature, affecting the hypothalamus and/or sweat
and loses two liters of sweat per hour, total loss of sodium
glands, delaying the starting of sweat and peripheral va-
is 240 mEq, i.e., 10% of the total extracellular space Na+.
sodilation during exercise.
Such loss would be irrelevant, were it not for the risk of
Dehydration affects aerobic performance, decreases car-
hyponatremia, a concentration of serum sodium less than
diac output due to reduction in the volume of blood, and
130 mEq·l-1, due to a fluid replacement with sodium-free
increases heart rate. These changes are more accentuated
or low-sodium fluids, particularly in lengthy events. Re-
in warm and humid climates, as higher skin vasodilatation
duction of serum osmolarity produces an osmotic gradient
transfers a good portion of blood flow to peripheral, rather
between blood and brain, causing apathy, nausea, vomit-
than musculoskeletal vessels, leading to significant reduc-
ing, altered perception, seizures, which are some of the
tion of blood pressure, venous return, and cardiac output.
neurological signs of hyponatremia. Including sodium in
Fluid replacement in a volume equal to loss of water through
rehydrating beverages allows higher intestinal absorption
sweat may prevent a decrease in ventricular output, and is
of water and carbohydrates during and after exercise. This
beneficial for thermal regulation as it enhances peripheral
happens because glucose transportation at the enterocyte
blood flow, facilitating internal heat to be transferred to
mucosa is coupled with sodium transportation, leading to
the periphery.
a higher absorption of water.
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

In lengthy exercises, which take longer than one hour,
ing easy, interrupting the exercise as little as possible.
it is recommended the drinking of fluids with 0.5 to 0.7
After the exercise, one should keep on drinking fluids
g/l (20 to 30 mEq·l-1) of sodium, which corresponds to a
to make up for additional losses of water through urine
similar or even lower concentration as in the sweat of
and sweat. One should take the opportunity to ingest
an adult. (Recommendation status A and evidence de-
carbohydrates, about 50 g of glucose on average within
gree 2).
the first two hours after the exercise, for re-synthesis of
muscular glucogen to take place, along with a swift stor-

age of muscular and hepatic glucogen. (Recommenda-
The intake of carbohydrates during a lengthy exer-
tion status A and evidence degree 2).
cise enhances performance and may delay fatigue in
Even if a good hydration during lengthy exercises under
those sports that involve intermittent, high-intensity
heat favors thermoregulatory response and performance,
exercises. Carbohydrate intake prevents glucose levels
one cannot ensure that, in extreme thermal stress it is enough
to fall after two hours of exercise. The necessary carbo-
to prevent fatigue or thermal shock. Specific recommen-
hydrate replacement to maintain serum glucose levels
dations have been made by the American Academy of Pe-
and delay fatigue is of 30 to 60 g/hour, with concentra-
diatrics Sports Medicine and Fitness Committee (see Ta-
tion ranging from de 4 to 8 g/deciliter. It is to be stressed
ble below). The degree of thermal stress follows the Wet
that there are publications showing that a beverage with
Bulb and Globe Temperature (WBGT) index, which com-
8% carbohydrate is not absorbed nor allow a swift gas-
bines measurements for air temperature (Tdb), humidity
tric emptying as water or beverages with 6% carbohy-
(Twb), and solar radiation (Tg), under the equation WBGT
drate. It is preferred that a mixture of glucose, fructose
= 0.7 Twb + 0.2 Tg + 0.1 Tdb.
and sacarose be used. The single use of fructose may
cause gastrointestinal disorder. (Recommendation sta-
tus A and evidence degree 2).

Indicated restriction of physical activities
relating to thermal stress
Other elements that affect effectiveness of a sports
Activities restriction
Gastric emptying is facilitated by intake of low-calories
< 24
Any activity is allowed. In lengthy activities, ob-
serve for initial signs of hyperthermia and de-
fluids, and intestinal absorption is optimized with isosmotic
fluids between 200 and 260 mosmol/kg. Intake of hyper-
One should make more prolonged intervals un-
tonic fluids could cause body water to be secreted to the
der the shade, and fluid intake every 15 minutes.
intestinal lumen. A number of other factors related to the
Those who are not used to heat or present any
taste of the fluid affect spontaneous intake, such as tem-
other risk factor should interrupt their activities.
perature, sweetness, intensity of flavor and acidity, in ad-
For all the others, activities should be limited.
dition to sensation of thirst and personal preferences.
> 29
Any athletic activity should be canceled.
Recommendations concerning fluid replacement
American Academy of Pediatrics, 2000.
One should intake fluids before, during and after
practicing exercise. To ensure a good hydration at the
beginning of the exercise, it is recommended the drink-
ing of about 250 to 500 ml of water two hours before the

exercise. During the exercise, fluid intake should begin
The benefits of a proper intake of proteins for those who
within the first 15 minutes, and kept on at every 15 to
practice regular physical activity are well documented in
20 minutes. The volume to be taken ranges according
the international literature. For the proper amount of pro-
to sweat rates, from 500 to 2,000 ml/hour. If the activity
tein intake to be established, before anything else it is nec-
lasts for more than one hour, or if it is intense, of inter-
essary to establish, in addition to individual features (gen-
mittent type, even lasting less than one hour, one should
der, age, anthropometric profile, health status, etc.), basic
replace carbohydrate in the amount of 30 to 60 g·h-1
parameters on the physical activity practiced, such as in-
and Na+ in the amount of 0.5 to 0.7 g·l-1. The tempera-
tensity, duration and frequency. It is recommended for
ture of the beverage should range from 15 to 22oC, and
sedentary individuals the intake of 0.8 g of protein per
flavored according to individual preference. The bever-
kg/day. For active individuals, 1.2 to 1.4 g/kg/day meet
age should be easy to reach, in bottles that make drink-
their needs. Athletes and individuals aiming muscular
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

hypertrophy have their needs met with the maximum
istered. Thus its use to favor immune response after in-
intake of 1.8 g/kg/day. These needs may be fulfilled by a
tense physical activity is not justified. (Recommenda-
balanced meal, unless there is a special situation. (Rec-
tion status E and evidence degree 7).
ommendation status A and evidence degree 2).
Ornitine and arginine are amino acids that, taken in-
Studies recommend that the use of protein supplements,
travenously, promote higher secretion of growth hor-
such as milk serum protein or egg-white albumin, should
mone, but are ineffective if orally administered. (Rec-
be in accordance with total intake of protein. Additional
ommendation status E and evidence degree 7).
intake of such protein supplements over the daily needs
(1.8 g/kg/day) does not determine gain in muscular mass
nor promotes performance enhancement.
Lately, in the sports area, the use of creatine supplement
The intake of proteins after physical exercise for hyper-
is being related to potential ergogenic effects that would re-
trophy favors the increase of muscular mass when com-
flect in increased resistance to strain in short-duration, high
bined with intake of carbohydrates, reducing protein deg-
intensity activities, and muscular mass augmentation. The
radation. Such intake should be in accordance with total
use of creatine as an ergogenic resource in prolonged lengthy
intake of proteins and calories. The increase of muscular is
physical activities has no support in scientific literature.
consequence of training, like protein demand, but the re-
Even though with controversial results, a number of stud-
verse is not true.
ies have suggested that creatine would have ergogenic ef-
fects for those individuals whose intake of creatine from
Amino acids
food is little, such as vegetarians and elders, and only for
The intake of amino acids as a food supplement has been
these specific cases its use is recommended, upon assess-
suggested as a strategy to meet specific metabolic require-
ment of a specialized professional, either physician or die-
ments for the practice of exercises. According to some stud-
titian, though yet with a low recommendation status.
ies, the intake of essential amino acids after intense training,
It is permitted the usage, always as an exception, only
associated to carbohydrate solutions, allows for a better re-
for competitive athletes participating in high-intensity
covery from the effort, followed by augment of muscular
and short lasting events, i.e., activities involving pre-
mass. Only essential amino acids have their use supported
dominantly phosphagens. Therefore, even in these cas-
by the literature as beneficial. The effects of supplementa-
es, creatine should not be widely used, but accepted in
tion with branch-chained amino acids (BCAA) in sports per-
rare occasions (Recommendation status D and evidence
formance are discordant, and most studies show it provides
degree 4). For the other athletes, the recommendation
no benefits in performance. There is a lack of scientific stud-
is not to use creatine (Recommendation status E).
ies with consistent information on the ergonogenic advan-
tages of such supplementation and on occurrence of side
The use of ?-hydroxy-?-methylbutirate (
HMB) is being
considered a potential agent to enhance strength and lean
Special considerations
body mass. Its action would be anti-catabolic, but it lacks
Branch-chained amino acids – leucine, isoleucine and
scientific studies that prove, without a doubt, the effective-
valine – being potent modulators of tryptophane re-
ness of this supplement for such ergogenic action other
uptake by the central nervous system, would foster tol-
than in some specific cases, such as elders who take part in
erance to prolonged physical strain. However, these
physical exercise programs. For the overall population,
data, which have been reported by some studies, are
even for competition athletes, its use is not recommend-
difficult to be duplicated, and the use of these amino
ed; on the contrary, recommendation is for it not to be
acids for ergogenic purposes is not justified. Another
used. (Recommendation status D and evidence degree 7).
aspect to be considered in branch-chained amino acids
is their use to enhance the immune system after intense
physical activity, but for this, more significant scientific

Illicit drugs are those whose use breaks ethical and dis-
evidence is also lacking. (Recommendation status E and
ciplinary codes, according to the World Anti-doping Agency
evidence degree 7).
and the International Olympic Committee (IOC), and may
Glutamine is an amino acid that acts as nutrient for
lead to punishments to athletes, coaches, physicians and
fast dividing cells, such as intestinal and immune sys-
officials. A list of forbidden drugs and methods, approved
tem cells. Its high use by intestinal cells does not make
on September 1st, 2001, is in the Appendix A of the Olym-
it available to other body areas when it is orally admin-
pic Movement Anti-doping Code.
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

I. Classes of forbidden drugs:
Some results are positive when drugs are present in the
urine over a specified level, such as caffeine, catine, ephe-
A. Stimulants;
drine, methylephedrine, phenylpropenilamine (phenilpro-
B. Narcotics;
panolamine), morphine and pseudoephedrine. To these, one
C. Anabolic agents:
adds nandrolone precursory substances. There is also a
1. Androgen anabolic steroids;
ceiling concentration for
2. Beta-2 agonists;
THC, to protect passive smoking.
Salbutamol is considered to be stimulant over a specific
D. Diuretics;
concentration, and anabolic agent over another, ten-fold
E. Peptide, mimetic hormones and analogues:
higher. And last, testosterone/epitestosterone ratio will be
1. Chorionic gonadotrophic hormone (hCG) (only for
considered doping if higher than 6.
male athletes);
Androgen anabolic steroids, peptide hormones and di-
2. Pituitary and synthetic gonadotropins (LH) (only for
uretics cannot be used unless specific authorization from a
male athletes);
relevant medical official for a particular sport or competi-
3. Corticotrophines (ACTH, tetracosactide);
tion. In case of proven medical indication, the specialized
4. Growth hormone (hGH);
physician can prescribe any drug, even if theoretically il-
5. Insulin-type growth factor-1 (IGF-1)
licit, and a relevant medical officer should expressly au-
Precursors and analogues to these hormones are also for-
thorize it. Even though the most important reasons for a
sports physician not to prescribe doping drugs are of ethi-
6. Erythropoietin (EPO);
cal and moral nature, it is also important to understand the
7. Insulin (except for insulin-dependent athletes)
medical problems related to the use of such drugs. Ath-
The presence of an abnormal concentration of an en-
letes are entitled to know the relative risks of an eventual
dogenous hormone (listed above, in class E) or its diag-
inadequate choice of drug, and discussing this issue is also
nostic markers in an athlet’s urine is a transgression, un-
a task of a team’s physician. The activity of the specialized
less due to a condition peculiar to the individual.
sports physician is regulated by ethics codes of the World
II. Forbidden methods:
Medical Association, International Federation of Sports
Medicine and the IOC.
1. Blood doping: it is the intravenous infusion of blood,
red cells and/or similar blood products. It may be preceded
Problems related to the use of food supplements
by withdrawing blood from an athlete, who goes on train-
Due to an increase in the number of positive cases for
ing with blood deficiency;
nandrolone on high performance sports from 1997 on, the
2. Dispensation of artificial oxygen transporters or plas-
Sports Council of the United Kingdom appointed a com-
ma expanders;
mittee of experts to analyze the reasons for this problem,
3. Pharmacological, chemical or physical manipulation
and concluded that there is no endogenous production of
of urine.
this hormone in humans, at least not in amounts above the
established by the IOC for its accredited labs to consider
III. Classes of drugs forbidden in some circumstances:
the amount positive for doping.
1. Alcohol;
The presence of steroids in food supplements and vege-
2. Cannabinoids;
table preparations, such as vitamins, creatines, and amino
3. Local anesthetics;
acids has been detected, but it was not stated in their la-
4. Glucocorticoids;
bels. IOC Medical Committee, due to flaws in legislation
5. Beta-blockers.
of many countries on quality control for manufacturing,
It is to be mentioned that some drugs may be licit at some
decided to warn on the risks of such products to be used. A
circumstances and illicit at others. Such is the case of stim-
study financed by IOC (available in its web page) shows
ulants, analgesic narcotics and corticosteroids, which may
that of 634 supplements analyzed by the Cologne Anti-
be used in some medical situations during training period,
doping Laboratory from 215 suppliers of 13 countries, 94
but cannot be used before a competition. The use of some
of those (14.8%) contained hormone precursors not stated
illicit drugs may lead to legal prosecution, for infringement
in their labels and that could be positive for doping. Among
of the Penal Code. The Brazilian Olympics Committee reg-
those, 24.5% had testosterone precursors, and 24.5% nan-
ularly publishes a bulletin listing the brand name of licit drugs
drolone precursors. For this reason, echoing IOC recom-
according to symptoms, and illicit pharmacological classes
mendations, we advise Sports Medicine professionals to
of drugs, in accordance with IOC regulations.
take extreme caution when prescribing such substances.
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

Benefits for sports
Potential risks and other remarks
Performance improvement
Increase of blood pressure, heart rate, propensity to cardiac arrhyth-
due to increase in aggressive-
mia, coronary artery spasm and myocardial ischemia in susceptible in-
ness and strength, better flow
dividuals. May cause sleep disorders. May also cause tremors, agita-
of thought, less drowsiness
tion, lack of motor coordination. In humid settings, there is risk of death
and fatigue. They help reduc-
due to heart failure. May cause psychological dependency.
ing fat tissue.
Control of pain, cough, dysp-
Dangerous inhibition of pain in injured athletes. Risk of physical addic-
nea, headaches and analge-
tion and withdrawal syndrome. Indicated for deep analgesia.
Increase if protein synthesis,
Indicated for primary male hypogonadism, refractory anemia, angion-
augmenting muscular mass,
eurotic hereditary edema, and muscular dystrophias (AIDS and rheu-
strength and power. Retention
matic diseases). Toxic effects are hydrosaline retention forming edema;
of nitrogen, sodium, potas-
high blood pressure, increase of LDL cholesterol, decrease of HDL cho-
sium, chloride and water is
lesterol, thyroid dysfunction, mood and sleep disorders. With steroids
with 17 alpha position modified, there can be changes in hepatic func-
tion, jaundice and hepatic adenocarcinoma. All androgenic steroids in-
crease aggressiveness. There is no circumstance under which andro-
genic anabolic steroids should be given to healthy individuals.
Increase of lean body mass
Anxiety, tremors, headaches, high blood pressure and cardiac
and decrease of body fat.
arrhythmias. They may cause hyperglycemia, hypokalemia, increase
in lactate and free fatty acids.
Cause rapid weight loss. De-
Among other indications, they are used to control high blood pressure.
crease concentration of sol-
They are forbidden because they are masking agents for doping drugs,
utes in the urine (mask agent).
as they decrease solute concentration in the urine; they promote a swift
weigh loss, thus allowing an athlete to compete in a weight category
lower than his, thus establishing an artificial and illicit advantage.
Increase of muscular volume
Increase nitrogen retention and assimilation of amino acids at the tis-
and power.
sue, increasing lean weight. Indicated for growth disorders, upon care-
ful medical assessment.
Increase in red blood cells,
Indicated to treat anemia, particularly in patients with chronic renal dis-
and consequently aerobic ca-
ease, where synthesis of this hormone is reduced.
(EPO) (8)
Being taken as an injection, it may cause local pain and dissemination
of infectious diseases. An excessive increase of the hematocrit decreases
speed of capillary perfusion, which decreases tissue oxygenation and
compromises performance. Blood transfusion with the purpose or rais-
ing hematocrit may cause severe allergic reactions, acute hemolysis,
hemodynamic overload, metabolic unbalance, and transmission of in-
fectious diseases.
Decrease of anxiety and
They favor performance in sports that require little muscular effort and
tremor, decrease of heart rate
high concentration and balance, such as shooting, modern pentathlon,
and blood pressure.
bow and arrow, ornamental diving, sailing, horsebackriding. In shoot-
ing, particularly with a pistol, a lesser heart rate means a longer dias-
tole time between each beat, allowing more accuracy in aiming.
Feeling of relaxation, decrease
Compromise vision, physical and psychological performance. Decrease
of anxiety.
memory, learning capacity and serum testosterone. Social drug. In a
synthetic form it is used as an antiemetic.
Rev Bras Med Esporte _ Vol. 9, Nº 2 – Mar/Abr, 2003

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