Whether they put in a perfunctory 20 minutes of heart-healthy cardio three
times per week or seek momentous victory in competitive sports, physically
active consumers remain interested in a vast array of sports nutrition products
designed to optimize performance and support the physical rigors of getting fit.
Building Blocks
Building lean body mass is a key goal of many physically active individuals.
Supplementation with protein is therefore a cornerstone of many training
programs. Supplemental protein is typically derived from two sources: soy (as
soy protein) and milk (as whey protein or casein).
Soy is a popular protein source among individuals looking to build muscle as
it is a vegetarian source of a comprehensive array of amino acids. In addition
to promoting muscle growth, soy protein supports existing lean body mass. In a
randomized, controlled German study on pre-obese and obese subjects,
participants with a body mass index (BMI) between 27.5 and 35 fed a diet rich in
soy protein lost weight and fat mass but experienced no change in lean body
mass; the researchers concluded a high-soy protein and low-fat diet can improve
body composition in overweight and obese people by promoting fat loss but
preserving muscle mass.1 Similarly, a Japanese study on rats
subjected to treadmill exercise found animals that consumed diets containing soy
protein avoided exercise-induced protein degradation of skeletal muscle.2
Soy protein is also favored
by the physically active for benefits beyond its muscle-promoting aptitude.
Unlike some sources of supplemental protein, soy protein has antioxidant
properties3,4 as well as isoflavones that fight cancer and
osteoporosis, lower low-density lipoprotein (LDL) cholesterol levels and reduce
the symptoms of menopause5 as well as lower various risk factors for
cardiovascular disease.6
Whey protein, a dairy-based source of amino acids, is an excellent source of
raw materials for bodies subjected to resistance training. Its branched-chain
amino acids (BCAAs)—leucine, isoleucine and valine—contribute
to muscle growth and regeneration. When combined with a resistance training
program, whey protein has been shown to increase body cell mass, muscle mass and
muscle strength.7,8 In an unpublished study presented at an annual
convention of the American College of Sports Medicine, 33 males were randomized
to receive whey protein isolate (as VP2 from AST Sports Science), micronized
creatine plus VP2, micronized creatine plus carbohydrate or a carbohydrate-only
placebo9. A week before and a week following a resistance training
program, test subjects’ muscle fibers were examined by tissue biopsy. All test
groups showed better gains in strength and muscle fiber cross-sectional area
(CSA) as compared to placebo; however, the micronized creatine plus VP2 and VP2
groups achieved the greatest gains.
Casein, a tasteless, odorless protein precipitated from milk by rennin, may
also increase strength during resistance training. In a study conducted at
Brigham and Women’s Hospital in Boston, casein hydrolysate produced a greater
mean increase in chest, shoulder and leg strength than whey protein hydrolysate.10
The researchers linked the greater strength increases in the caseinsupplemented
group with improved nitrogen retention and overall anticatabolic effects related
to the peptide components of the casein hydrolysate.
According to Reto Rieder with DSM Food Specialties, the combination of casein
hydrolysate and carbohydrates shortens recovery time following exercise. One
recent study conducted at Maastricht University, The Netherlands, involved
athletes who were administered a drink containing 4.2 g casein hydrolysate
prepared through a proprietary process (as PeptoPro®, by DSM Food Specialties)
plus 8.2 g/100 ml carbohydrates or a carbohydrate-only drink (8.2 g/100 ml
carbohydrates). The athletes exercised to exhaustion and recovered for five
hours, during which they were given the casein hydrolysate plus carbohydrate
drink or the carbohydrate-only drink, and then exercised again. Athletes
administered the casein hydrolysate plus carbohydrates drink had twice the
production of insulin after exercise and significantly reduced plasma glucose
levels as compared to athletes given the carbohydrate-only drink.
Rieder added research suggests casein hydrolysate enhances endurance. He
cited a proprietary double blind, controlled study wherein 15 cyclists rode at
75 percent VO2 max until exhausted, then recovered for 12 to 15 hours. The
cyclists then rode at 85 percent VO2 max until exhausted. Throughout the study,
the participants were administered either a casein hydrolysate protein drink
(1.8 percent casein hydrolysate as PeptoPro, plus 7.3 percent carbohydrates), or
a carbohydrate-only drink (7.3 percent carbohydrate). Plasma levels of creatine
phosphokinase—a marker of muscle cell damage—were five times lower in cyclists
given the casein hydrolysate plus carbohydrates drink than in test subjects
given the carbohydrate-only drink.
The most abundant amino acid in the body is glutamine. In situations
of heightened energy expenditure, glutamine is converted to glucose—the most
basic form of energy—to provide ergogenic support. Research indicates glutamine
may spare muscle proteins by combating negative nitrogen balance and muscle
wasting that occurs in individuals with acute injury.11
The amino acids lysine and methionine are synthesized within the body to
produce carnitine, an amino acid metabolite with the primary function of
supplying cellular mitochondria with fatty acids for energy production.12
Studies have shown supplemental carnitine (L-carnitine) facilitates training,
competition, and recovery from strenuous exercise.13 Carnitine has
also been shown to depress plasma levels of lactate following strenuous
exercise,14 and is thought to delay fatigue as well as promote muscle
recovery.
A controlled study at the University of Cordoba in Spain found supplemental
carnitine in horses encouraged muscular adaptations to training by increasing
type IIA muscle fibers in muscle composition as well as the capillary-to-fiber
ratio and levels of muscle glycogen.15 The researchers noted these
adaptations disappeared after cessation of training and concluded L-carnitine
“should be beneficial” to athletic performance.
Three studies on a proprietary carnitine supplement (LCarnipure ®, an
L-carnitine L-tartrate ingredient supplied by Lonza) demonstrated L-carnitine
may be a useful tool for athletes. In the first study, 12 slightly overweight
subjects were put on a regular diet with or without 3 g/d of L-carnitine (as
L-Carnipure) for 10 days.16 Test subjects’ body fat mass, total body
water and lean body mass measured by bioelectric impedance analysis suggested
L-carnitine increased fat oxidation but spared lean body mass. In the second
study, L-carnitine L-tartrate (as L-Carnipure) helped control participants’
blood toxin levels following high-repetition squats, indicating the supplement
promoted recovery from exercise.17 In the third study, eight weeks of
supplementation with L-carnitine L-tartrate (as L-Carnipure) enhanced fat
utilization and maximum work capacity during exercise in 14 active males
administered identical diets 48 hours prior to bouts of steady-state cycling at
baseline and every two weeks during the trial.18
The mineral magnesium plays a role in the synthesis of B vitamins;
assists in the manufacture of proteins, fatty acids and adenosine triphosphate
(ATP); regulates membrane stability as well as neuromuscular, cardiovascular,
immune, and hormonal functions; and is a crucial cofactor in numerous metabolic
reactions. Depletion of magnesium through exercise or inadequate dietary intake
may impair energy metabolism efficiency and the capacity for physical work.19
Low magnesium levels within the body also heighten oxygen requirements for
submaximal exercise and lower endurance.20
Zinc and iron are two other minerals crucial to optimal athletic
performance. Zinc, a component of more than 300 enzymes involved in various
physiological processes including protein synthesis, is important for bone
health in athletes.21 Insufficient iron levels within the body may
lead to iron-deficiency anemia, a cause of severe fatigue. In a study at the
State University of New York, Albany, iron supplementation was found to improve
performance during leg extension exercises in 20 iron-depleted women
administered supplemental iron or placebo for six weeks.22
Additionally, researchers at the University of Oregon, Corvallis, found iron
supplementation may help prevent exercise-induced menstrual dysfunction, a
factor in poor bone health.23
The mineral chromium may have thermogenic effects within the body. As
a regulator of insulin-mediated transport of glucose, amino acids and fat,
chromium may help build muscle mass. An eight-week in vivo study conducted on 20
overweight women given 600 mcg/d of niacin-bound chromium (as ChromeMate® from
InterHealth Nutraceuticals) or placebo in a randomized, crossover, double blind
design indicated chromium supplementation significantly increased fat loss and
spared muscle mass in test subjects.24
Chromium’s popularity in sports nutrition also stems from its alleged
ergogenic qualities.25 In a study involving elite cyclists and
chromium (as ChromeMate), researchers noted improved exercise performance as
measured by power output among athletes supplemented with chromium.26
And a proprietary study conducted by Nutrition 21 and researchers from the
University of Vermont Medical College, Burlington, and presented at one of the
Scientific Sessions of the American Diabetes Association showed chromium in the
form of chromium picolinate (as Chromax®, by Nutrition 21) improves strength and
endurance by down-regulating tumor necrosis factor alpha and ubiquitin proteins
involved in carbohydrate metabolism.
Creatine, an amino acid derivative occurring naturally in skeletal
muscles and to a lesser degree in the heart, brain and testes27, is
touted as a pathway to increased muscle mass. Believed to increase strength and
performance, supplemental creatine is converted to phosphocreatine (PCr)—an
energy source ideal for activities requiring high-intensity bursts of activity,
such as sprinting and weightlifting—within the body.
Two research reviews suggest creatine supplementation produces
musculoskeletal gains and improves body composition as well as endurance. The
first review stated a program of creatine supplementation and resistance
training can increase skeletal muscle creatine concentrations, thereby promoting
lean body mass, power and strength,28 while the second review
indicated 70 percent of approximately 300 studies on creatine’s potential
ergogenic benefits have reported statistically significant results.29
The second review also mentioned clinical data have demonstrated creatine
supplementation promotes significant gains in strength, fat-free mass and
performance in rigorous exercise.
At the University of Saskatchewan in Canada, a six-week controlled clinical
trial on six males and five females given creatine or placebo and asked to
perform single-limb exercises with one side of the body two times per week and
with the opposite limbs two times per week found supplementation with creatine
resulted in greater increase in muscle thickness of the arms, particularly in
males.30 Similarly, a Belgian study investigating the effects of oral
creatine supplementation on muscle PCr concentration, strength and body
composition in 19 young female volunteers during 10 weeks of resistance training
found long-term creatine supplementation enhanced the progress of muscle
strength during resistance training in sedentary females.31
Supplemental magnesium and creatine are frequently formulated in concert,
since both are linked to production of energyproviding ATP. According to a
placebocontrolled clinical trial conducted at Western Washington University,
Bellingham, magnesium-creatine chelate (as Creatine MagnaPower from Albion
Advanced Nutrition) may help runners delay exhaustion through its effects on
accumulated oxygen deficit.32 Magnesium-creatine chelate (as Creatine
MagnaPower) also enhanced physical performance in animals, in comparison to
physical performance in animals supplemented with creatine monohydrate, creatine
monohydrate plus magnesium oxide, creatine monohydrate plus magnesium amino acid
chelate, or placebo.33 The author of the study concluded
magnesium-creatine chelate (as Creatine MagnaPower) enhanced the animals’
ability to generate and regenerate ATP for muscular performance.
Fat Burners
Conjugated linoleic acid (CLA), an omega-6 fatty acid occurring naturally
in beef, lamb, dairy products and safflower oil, may promote fat loss without
affecting lean body mass or changes in diet.34 In a recent 12-month
study, CLA reduced body fat mass (BFM) and increased in lean body mass (LBM) by
as much as 9 percent in overweight adults.35 The double blind,
placebo-controlled study randomized 180 men and women, aged 18 to 65, and with a
BMI of 25 kg/m2 to 30 kg/m2, into three groups administered either capsules
containing 4.5 g/d of CLA-free fatty acid, 4.5 g/d of CLA-triglycerides (as
Tonalin®, from Cognis Nutrition & Health) or a placebo of 4.5 g/d olive oil.
Scientists monitored participants’ body weight and BMI, as well as body and
blood composition. BFM decreased significantly in both groups administered CLA
compared to placebo, and the CLA-free fatty acid group showed an increase in LBM
compared to placebo. The authors of the study noted the results were not
produced by changes in diet or exercise, and concluded both forms of CLA cause a
significant decrease in body fat mass over a one-year period in healthy,
overweight adults.
Another study on CLA and body composition investigated the effects of six
months of supplementation with 7 g/d CLA (as Clarinol™, by Lipid Nutrition).36
Seven beginners and seven advanced male and female resistance-trained athletes
performed a standardized training routine three times per week and were assessed
for body mass index, body composition and nutrient intake. In spite of a higher
energy intake, a significant reduction of body fat and an increase in body cell
mass was observed in both groups. In addition, the effects noted in the
experienced group were not greater than those seen in the novice group.
Forskolin, the root extract of the herb Coleus forskohlii
is thought to optimize body composition by reducing fat mass while
sparing muscle. Forskolin may reduce body fat by stimulating 3’5’adenosine
monophosphate (AMP)—a compound involved in the release of fatty acids from
adipose tissue—leading to improved thermogenic response as well as increased
basal metabolic rate and body fat metabolism. A two-month study in six
overweight women administered 500 mg/d forskolin (as ForsLean® by Sabinsa Corp.)
indicated supplementation with the botanical caused a significant decrease in
body fat mass and an increase in lean body mass.37
Another herb thought to decrease body fat and support lean muscle mass is
Eurycoma longifolia jack (longifolia), a Malaysian shrub of the
Simaroubaceace family. The botanical may be anabolic; according to unpublished
studies, longifolia boosts production of testosterone in men by stimulating
steroidogenesis in the testis and the adrenals as well as helping to reduce sex
hormone binding globulin (SHBG). In an unpublished Malaysian study, 14 test
subjects were administered longifolia (as LJ100 standardized longifolia extract
with 22 percent bioactive eurypeptides, supplied by HP Ingredients) and put on a
weight-training program. At the conclusion of the study, the test subjects had
more lean body mass as well as less fat mass than at baseline.38 The
researchers linked these results to a possible rise in testosterone levels
following supplementation with longifolia.
Green tea is a botanical marketed for its ergogenic and thermogenic
properties. Japanese researchers found green tea extract (GTE) increased
endurance capacity, energy metabolism and fat oxidation in mice subjected to a
swimming challenge.39 Another GTE study suggested the herb increased
metabolism and fat oxidation, respiratory quotient and urinary excretion of
nitrogen and catecholamines in a 24-hour human study, suggesting thermogenic
action.40 The researchers concluded GTE promotes fat oxidation for
reasons beyond its caffeine content; and may play a role in the control of body
composition via sympathetic activation of thermogenesis, fat oxidation, or both.
Performance Enhancers
Several B vitamins play a role in sports nutrition, as they are
involved in energy metabolism. Because exercise stresses metabolic pathways
dependent on vitamin B-1 (thiamine), vitamin B-2 (riboflavin), and
vitamin B-6 (pyridoxine, pyridoxal and pyridoxamine), physically active
individuals may need more of these vitamins than their sedentary counterparts.41
Within the body, vitamin B3, as niacin
(or nicotinic acid) and niacinamide (or nicotinamide), helps release
energy from carbohydrates. Australian researchers at the Deakin University in
Burwood found niacin possibly improved carbohydrate metabolism during cycling in
unconditioned women by increasing glycogen utilization, which compensated for
carbohydrate oxidation.42
Another energy-enhancing supplement found naturally in the body is
pyruvate, the stable form of pyruvic acid. Pyruvate stimulates ATP
production, and is thought to promote energy by enhancing glucose assimilation
by the muscles from the bloodstream. A six-week, double blind,
placebo-controlled study in healthy overweight Caucasian men and women showed
pyruvate supplementation in conjunction with mild physical activity resulted in
a significant decrease in body weight and fat mass.43 Twenty-six test
subjects received placebo or pyruvate and performed a 45 to 60 min
aerobic/anaerobic routine three days/week. After six weeks of treatment, there
was a statistically significant decrease in weight and body fat in the pyruvate
group. In addition, individuals supplemented with pyruvate showed improvements
in Profile of Mood States fatigue and vigor scores at six weeks (vigor) and four
and six weeks (fatigue).
The herb guarana, an evergreen vine indigenous to the Amazon basin,
stimulates the nervous system and increases metabolism.44 The herb
may also suppress exercise-induced hypoglycemia. A Japanese study showed a water
extract of guarana (500 mg/kg) increased blood glucose level, decreased liver
glycogen content and significantly suppressed exercise-induced hypoglycemia in
mice within 60 minutes of oral maltose administration.45
Bovine colostrum, a pre-milk compound, may be another performance
enhancer, particularly in terms of speed and endurance. In a double blind,
placebo-controlled trial, supplementation with 60 g/d of bovine colostrum (as
Intact™, supplied by La Belle) for eight weeks helped 35 elite field hockey
players improve sprint performance over players given a placebo of 60 g/d of
whey.46 Bovine colostrum protein powder also improved endurance,
running performance and recovery in a controlled clinical trial held at the
University of South Australia, Adelaide, in which subjects were administered 60
g/d of colostrum protein powder (as Intact) for eight weeks.47
Subjects given colostrum protein powder improved their exercise performance by
as much as 5.2 percent, possibly due to enhanced recovery. Bovine colostrum may
also increase lean body mass, as demonstrated by a study in active men and women
taking 20 g/d of bovine colostrum during eight weeks of resistance training.48
Promoting Recovery
Exercise produces several beneficial physiological outcomes such as improved
cardiovascular fitness and body composition, as well as stress reduction;
however, it also produces negative effects within the body including oxidative
damage, immuno-suppression and increased rate of infection. In addition, the
often violent mechanical impulsion of exercise commonly inflicts wear and tear
on joints, tendons, ligaments and other cartilaginous areas within the body.
Both strenuous, long-duration exercise and exhaustive sprint training
overwhelm the body’s capacity to detoxify reactive oxygen species (ROS)—strong
oxidants that damage various biological molecules and cell structures—producing
oxidative stress.1 However, antioxidants, vitamins and minerals
combat oxidative stress to help protect and repair healthy muscles, bones and
other infrastructure.
Vitamin E is a vitamin antioxidant thought to inhibit
free-radical-induced muscle damage.2 In one clinical trial in older
and younger subjects performing eccentric exercise, vitamin E substantially
increased circulating neutrophils, white blood cells that engulf pathogenic
invaders through phagocytosis and digest them in enzyme sacs.3 Intake
of vitamin E also increases activity of creatine kinase (CK) activity (a marker
of cellular damage), suggesting increased skeletal muscle repair, and has been
associated with enhanced glucose tolerance and insulin action as well as
improved lipoprotein status.4 Vitamin E may also help to prevent the
production of oxidized low-density lipoprotein (LDL) cholesterol caused by
strenuous endurance exercise.5
Vitamin C is involved in a number of biochemical pathways important to
exercise metabolism and the health of exercising individuals.6 A
controlled Spanish study found vitamin C supplementation increased erythrocyte
antioxidant enzymes and plasma antioxidants during athletic competition and
short-term recovery, while subjects not supplemented with vitamin C experienced
increases in uric acid and lactate dehydrogenase.7 The researchers
concluded vitamin C supplementation defends against oxidative stress and
prevents negative effects on erythrocyte integrity induced by exercise. A
clinical trial testing whether two weeks of vitamin C supplementation affected
recovery from an unaccustomed bout of exercise found supplemental vitamin C
produced “modest beneficial effects” on muscle soreness, muscle function and
plasma concentrations of malondialdehyde, suggesting prolonged vitamin C
supplementation promotes recovery from unaccustomed exercise. 8
The combination of vitamin E and vitamin C has been shown to decrease
exerciseinduced lipid peroxidation.9 One study at the University of
Oregon, Corvallis, found the combination of vitamins C and E prevented endurance
exercise-induced lipid peroxidation in ultramarathon runners. 10 In a
rat and treadmill study, the combination of the two was also shown to
significantly improve the body mass, total exercise duration and net mass of rat
quadriceps femoris. 11
Soy protein is popularly used to support muscle-building. Unlike some
sources of supplemental protein, soy protein also aids in recovery by
counteracting oxidative damage. In a nine-week, controlled study designed to
compare the efficacy of soy protein and whey protein in promoting lean body
mass, two groups of males administered daily servings of protein bars formulated
with 33 g soy protein or whey protein and put on an exercise plan both gained
muscle mass; however, only males supplemented with soy protein bars experienced
a positive post-training effect upon two antioxidant-related parameters.12
In a similar in vivo comparison study of soy protein versus whey protein
combined with moderate intensity weight resistance exercise, only soy protein
reduced oxidative stress, as revealed by lowered serum levels of lipid
peroxides.13 The antioxidant enzyme superoxide dismutase
(SOD) is a potent endogenous free-radical scavenger. Plasma levels of SOD
increase as a response to exercise-induced oxidative stress in erythrocytes.
Supplemental SOD may therefore help athletes counteract free-radical damage
induced by exercise. A fourweek Korean clinical trial evaluated the influence of
an oral preparation of SOD (1,500 IU/d as GliSODin®, supplied by P.L. Thomas &
Co.) on blood antioxidant profiles and plasma lactate levels following strenuous
exercise and found SOD positively affected the distribution and mobilization of
human antioxidant enzymes and reduced lactic acid buildup.14 In
another study, conducted at the Nippon Medical School in Japan, researchers
administered 300 mg/d of SOD (as GliSODin) to eight healthy individuals for six
days prior to intense exercise and found the increase in glucose consumption
during strenuous physical activity is directly related to the accumulation of
lactate in the blood flow and the SOD administered in the study significantly
prevented this effect.15
Other antioxidants useful to athletes include the carotenoid astaxanthin
as well as coenzyme Q10 (CoQ10).
Astaxanthin, a naturally occurring carotenoid pigment, functions as a
powerful antioxidant within the body. In a clinical trial conducted at the Kyoto
Prefectural University of Medicine in Japan, scientists examined the impact of
supplemental astaxanthin on oxidative damage induced by strenuous exercise in
mouse calf muscle and heart, and found astaxanthin reduced markers of oxidative
damage including 4-hydroxy-2- nonenal-modified protein and
8-hydroxy-2’-deoxyguanosine in gastrocnemius and heart, plasma CK activity, and
myeloperoxidase activity in gastrocnemius and heart.16 They concluded
astaxanthin attenuates exerciseinduced damage in mouse skeletal muscle and
heart, and inhibits an associated neutrophil infiltration responsible for
additional damage.
Astaxanthin may also counteract delayed onset muscular soreness (DOMS) as
well as increase endurance. An unpublished study conducted at the University of
Memphis showed perception of DOMS was attenuated in weight-trained males given
either 4 mg/d astaxanthin (as BioAstin®, supplied by Cyanotech Corp.; n=4) or
placebo (n=5) for a three-week loading phase preceding a bout of leg extension
exercise, and during a 12-day recovery phase. 17 Another unpublished
study conducted at the Karolinska institute in Gustavsberg, Sweden found 4 mg/d
of supplemental astaxanthin (also as BioAstin) improved strength and endurance
by almost three times in healthy young male subjects performing knee-bends.
18
CoQ10, a substance present in every cell in the body, aids in the delivery of
oxygen throughout biologically active molecules and supports mitochondrial
production of ATP. Finnish scientists discovered CoQ10 supplementation in a
double blind crossover study of 25 top-level cross-country skiers improved all
measured indexes of physical performance including aerobic exercise training
(AET), anaerobic exercise and VO2 max (the maximum amount of oxygen in
milliliters one can use in one minute per kilogram of body weight).
19
Another botanical popular with physically active consumers is extract of
French maritime pine bark. In a double blind, placebo-controlled,
crossover California State University study, 24 recreational athletes divided
into two test groups received either 200 mg/d French maritime pine bark extract
(as Pycnogenol®, from Natural Health Science) or placebo for one month.20
Endurance increased by 29.6 percent in the first group and by 13.7 percent in
the second group, over the control group. The composite endurance for both
groups after supplementation with French maritime pine bark extract increased by
a statistically significant 21 percent compared to placebo, and the results of
the trial led the scientists to conclude French maritime pine bark extract as
Pycnogenol significantly improved endurance compared to the control.
Symptoms including stiffness, pain, inflammation and loss of function suggest
an athlete’s cartilage has sustained motion-induced damage. Two supplements
taken to help counteract joint damage include glucosamine and
chondroitin sulfate. Glucosamine is an amino sugar believed to promote
cartilage formation and repair.
Chondroitin sulfate is a component of proteoglycans (PGs), proteins
responsible for cartilage’s elasticity.
Glucosamine may ease pain and restore motion in joints with exercise-induced
cartilage injury. In a study testing this idea, 46 subjects were randomly
assigned to receive 2,000 mg/d of glucosamine or a placebo over 12 weeks.21
Some degree of improvement in knee pain was reported by 88 percent of the
glucosamine group, while only 17 percent reported the same in the placebo group.
According to another knee study, chondroitin sulfate may reduce pain and
improve joint function.22 Subjects with symptomatic knee
osteoarthritis (n=120) were randomized into two groups to receive either 800
mg/d chondroitin sulfate or placebo for two three-month periods during one year.
Subjects reported a decrease in joint pain and an increase in range of motion,
while radiological progression revealed significantly decreased width in the
medial femoro-tibial joint space in weight-bearing Xrays of both knees.
Another dietary supplement touted for support of joint health is concentrated
milk proteins. A six-week, randomized, double blind, placebo-controlled trial
examining the outcome of milk protein concentrate supplementation on
osteoarthritic adults 19 years of age or greater (eight men and 34 women with a
mean age of 59 years) found 2,000 mg milk protein concentrate (as MicroLactin™,
a patented ingredient from Humanetics Corp.) administered twice daily was
effective in relieving symptoms of osteoarthritis, including joint pain, joint
stiffness and immobility, in this patient population.23 A double
blind, six-month study on runners found MicroLactin conferred benefits beyond
joint health, including perceived improvement in training, improved
five-kilometer race times, faster recovery time between training sessions,
decreased muscle damage, and a slight but significant decrease in body fat
percentage despite a slight increase in body weight.24
Preparations from Arnica montana (arnica) flowers have been used
traditionally for the treatment of inflammatory diseases. Sesquiterpene lactones
in arnica attack inflammatory processes by inhibiting the transcription
factors NF-kappa B and NF-AT at micromolar concentrations.25 As a
homeopathic treatment, arnica is potentially useful to the physically active as
it treats soreness and bruising caused by injury, overexertion and acute trauma.
A Brazillian study used a model of carrageenin-induced rat paw edema to test the
anti-inflammatory effects of arnica and found animals treated with Arnica
montana 6cH showed 30 percent inhibition compared to a control group.26
The researchers concluded pretreatment with Arnica montana 6cH blocked the
action of histamine in increasing vascular permeability in a model based on
histamine-induced increase of vascular permeability.
“Whether in the form of a topical cream, gel, or ointment, or as an oral
pellet, Arnica reduces pain, inflammation, swelling and bruising; this is
especially useful for athletes,” said Alissa Gould, spokeswoman for Boiron
Group. According to Gould, additional benefits are possible when Arnica is
combined with two other homeopathic medicines. “[The addition of] Sarcolacticum
acidum and Zincum oxydatum [to Arnica] reduces lactic acid build-up and
decreases muscle cramping, which helps increase stamina,” she said.
An unpublished placebo-controlled study supported by Boiron showed the
combination of these homeopathic ingredients (as Sportenine, manufactured by
Boiron) reduced fatigue recovery in rats subjected to a treadmill challenge as
evidenced by heart rate measurements taken during rest, exercise and recovery.
In a double blind study on 60 athletes whose pulse rates were monitored before,
during and after performing 30 leg flexes in 45 seconds, test subjects treated
with Arnica, Sarcolacticum acidum and Zincum oxydatum (as Sportenine)
recuperated faster than those not administered the combination of homeopathic
remedies. Athletes given the homeopathic ingredients and asked to run the
longest possible distance in a 12-minute period also experienced a significant
improvement in stamina as measured by increased VO2 max.
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Soy protein is also favored
by the physically active for benefits beyond its muscle-promoting aptitude.
Unlike some sources of supplemental protein, soy protein has antioxidant
properties3,4 as well as isoflavones that fight cancer and
osteoporosis, lower low-density lipoprotein (LDL) cholesterol levels and reduce
the symptoms of menopause5 as well as lower various risk factors for
cardiovascular disease.6