Archive for the ‘Baseball’ Category

Don’t drink alcohol. Take vitamins. Avoid eating eggs. We’ve heard these pieces of nutritional advice for years – but are they accurate?

Not necessarily, say two exercise physiologists who presented at the American College of Sports Medicine (ACSM) 11th-annual Health & Fitness Summit & Exposition in Dallas, Texas. Wendy Repovich, Ph.D., FACSM, and Janet Peterson, Dr.P.H., FACSM, set out to debunk the “Top 10 Nutrition Myths.”

According to Repovich and Peterson, these nutrition myths are:

10. Eating carbohydrates makes you fat. Cutting carbs from your diet may have short-term weight loss benefits due to water loss from a decrease in carbohydrate stores, but eating carbs in moderation does not directly lead to weight gain. The body uses carbs for energy, and going too long without them can cause lethargy.

9. Drink eight, 8-oz. glasses of water per day. You should replace water lost through breathing, excrement and sweating each day – but that doesn’t necessarily total 64 ounces of water. It’s hard to measure the exact amount of water you have consumed daily in food and drink, but if your urine is pale yellow, you’re doing a good job. If it’s a darker yellow, drink more H2O.

8. Brown grain products are whole grain products. Brown dyes and additives can give foods the deceiving appearance of whole grain. Read labels to be sure a food is whole grain, and try to get three-ounce equivalents of whole grains per day to reduce the risk of heart disease, diabetes, and stroke.

7. Eating eggs will raise your cholesterol. This myth began because egg yolks have the most concentrated amount of cholesterol of any food. However, there’s not enough cholesterol there to pose health risks if eggs are eaten in moderation. Studies suggest that eating one egg per day will not raise cholesterol levels and that eggs are actually a great source of nutrients.

6. All alcohol is bad for you. Again, moderation is key. Six ounces of wine and 12 ounces of beer are considered moderate amounts, and should not pose any adverse health effects to the average healthy adult. All alcohol is an anticoagulant and red wine also contains antioxidants, so drinking a small amount daily can be beneficial.

5. Vitamin supplements are necessary for everyone. If you eat a variety of fruits, vegetables, and whole grains, along with moderate amounts of a variety of low-fat dairy and protein and the right quantity of calories, you don’t need to supplement. Most Americans do not, so a multi-vitamin might be good. Special vitamin supplements are also recommended for people who are pregnant or have nutritional disorders.

4. Consuming extra protein is necessary to build muscle mass. Contrary to claims of some protein supplement companies, consuming extra protein does nothing to bulk up muscle unless you are also doing significant weight training at the same time. Even then the increased requirement can easily come from food. A potential problem with supplements is the body has to work overtime to get rid of excess protein, and can become distressed as a result.

3. Eating fiber causes problems if you have irritable bowel syndrome (IBS). There are two kinds of fiber: soluble and insoluble. Insoluble fiber can cause problems in IBS sufferers; soluble fiber, however, is more easily absorbed by the body and helps prevent constipation for those with IBS. Soluble fiber is found in most grains.

2. Eating immediately after a workout will improve recovery. Endurance athletes need to take in carbohydrates immediately after a workout to replace glycogen stores, and a small amount of protein with the drink enhances the effect. Drinking low-fat chocolate milk or a carbohydrate drink, like Gatorade, is better for the body, as they replace glycogen stores lost during exercise. Protein is not going to help build muscle, so strength athletes do not need to eat immediately following their workout.

1. Type 2 diabetes can be prevented by eating foods low on the glycemic index. High levels of glucose are not what “cause” diabetes; the disease is caused by the body’s resistance to insulin. Foods high on the glycemic index can cause glucose levels to spike, but this is just an indicator of the presence of diabetes, not the root cause.

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Article adapted by MD Sports Weblog from original press release.
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Contact: Communications and Public Information
American College of Sports Medicine

The American College of Sports Medicine is the largest sports medicine and exercise science organization in the world. More than 20,000 International, National and Regional members are dedicated to promoting and integrating scientific research, education and practical applications of sports medicine and exercise science to maintain and enhance physical performance, fitness, health and quality of life.

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Myostatin (MSTN) is a transforming growth factor-ß (TGF-ß) family member that plays a critical role in regulating skeletal muscle mass [1]. Mice engineered to carry a deletion of the Mstn gene have about a doubling of skeletal muscle mass throughout the body as a result of a combination of muscle fiber hyperplasia and hypertrophy [2]. Moreover, loss of myostatin activity resulting either from postnatal inactivation of the Mstn gene [3], [4] or following administration of various myostatin inhibitors to wild type adult mice [5][7] can also lead to significant muscle growth. Hence, myostatin appears to play as least two distinct roles, one to regulate the number of muscle fibers that are formed during development and a second to regulate growth of muscle fibers postnatally. The function of myostatin appears to have been conserved across species, as inactivating mutations in the myostatin gene have been demonstrated to cause increased muscling in cattle [8][11] , sheep [12], dogs [13] and humans [14]. As a result, there has been considerable effort directed at developing strategies to modulate myostatin activity in clinical settings where enhancing muscle growth may be beneficial. In this regard, loss of myostatin activity has been demonstrated to improve muscle mass and function in dystrophic mice [15][17] and to have beneficial effects on fat and glucose metabolism in mouse models of obesity and type II diabetes [18].

Myostatin is synthesized as a precursor protein that undergoes proteolytic processing to generate an N-terminal propeptide and a C-terminal dimer, which is the biologically active species. Following proteolytic processing, the propeptide remains bound to the C-terminal dimer and maintains it in an inactive, latent complex [6], [19], [20], which represents one of the major forms of myostatin that circulates in the blood [21], [22]. In addition to the propeptide, other binding proteins are capable of regulating myostatin activity in vitro, including follistatin [19], [21], FLRG [22], and Gasp-1 [23]. We previously showed that follistatin can also block myostatin activity in vivo; specifically, we showed that follistatin can ameliorate the cachexia induced by high level expression of myostatin in nude mice [21] and that transgenic mice expressing follistatin in muscle have dramatic increases in muscle mass [19]. Here, I show that overexpression of follistatin can also cause substantial muscle growth in mice lacking myostatin, demonstrating that other TGF-ß related ligands normally cooperate with myostatin to suppress muscle growth and that the capacity for enhancing muscle growth by targeting this signaling pathway is much larger than previously appreciated.

Results

Increased muscle mass in transgenic mice expressing FLRG

Previous studies have identified several proteins that are normally found in a complex with myostatin in the blood [22], [23]. One of these is the follistatin related protein, FLRG, which has been demonstrated to be capable of inhibiting myostatin activity in vitro. To determine whether FLRG can also inhibit myostatin activity in vivo, I generated a construct in which the FLRG coding sequence was placed downstream of a myosin light chain promoter/enhancer. From pronuclear injections of this construct, a total of four transgenic mouse lines (Z111A, Z111B, Z116A, and Z116B) were obtained containing independently segregating insertion sites. Each of these four transgenic lines was backcrossed at least 6 times to C57 BL/6 mice prior to analysis in order to control for genetic background effects. Northern analysis revealed that in three of these lines the transgene was expressed in skeletal muscles but not in any of the non-skeletal muscle tissues examined (Figure 1); in the fourth line, Z111B, the expression of the transgene was below the level of detection in these blots. As shown in Table 1, all four lines exhibited significant increases in muscle weights compared to wild type control mice. These increases were observed in all four muscles that were examined as well as in both sexes. Moreover, the rank order of magnitude of these increases correlated with the rank order of expression levels of the transgene; in the highest-expressing line, Z116A, muscle weights were increased by 57–81% in females and 87–116% in males compared to wild type mice. Hence, FLRG is capable of increasing muscle growth in a dose-dependent manner when expressed as a transgene in skeletal muscle.

The research was funded by grants from the NIH and the Muscular Dystrophy Association and by a gift from Merck Research Laboratories.

See http://www.jhu.edu/sejinlee/%20for%20more%20information for more information.
Citation: Lee S-J (2007) Quadrupling Muscle Mass in Mice by Targeting TGF-ß Signaling Pathways. PLoS ONE 2(8): e789. doi:10.1371/journal.pone.0000789

LINK TO THE PUBLISHED ARTICLE http://www.plosone.org/doi/pone.0000789

Source: Nick Zagorski
Johns Hopkins Medical Institutions

Although it’s too soon to recommend dropping by Starbucks before hitting the gym, a new study suggests that caffeine can help reduce the post-workout soreness that discourages some people from exercising.In a study to be published in the February issue of The Journal of Pain, a team of University of Georgia researchers finds that moderate doses of caffeine, roughly equivalent to two cups of coffee, cut post-workout muscle pain by up to 48 percent in a small sample of volunteers.

Lead author Victor Maridakis, a researcher in the department of kinesiology at the UGA College of Education, said the findings may be particularly relevant to people new to exercise, since they tend to experience the most soreness.

“If you can use caffeine to reduce the pain, it may make it easier to transition from that first week into a much longer exercise program,” he said.

Maridakis and his colleagues studied nine female college students who were not regular caffeine users and did not engage in regular resistance training. One and two days after an exercise session that caused moderate muscle soreness, the volunteers took either caffeine or a placebo and performed two different quadriceps (thigh) exercises, one designed to produce a maximal force, the other designed to generate a sub-maximal force. Those that consumed caffeine one-hour before the maximum force test had a 48 percent reduction in pain compared to the placebo group, while those that took caffeine before the sub-maximal test reported a 26 percent reduction in pain.

Caffeine has long been known to increase alertness and endurance, and a 2003 study led by UGA professor Patrick O’Connor found that caffeine reduces thigh pain during moderate-intensity cycling. O’Connor, who along with professors Kevin McCully and the late Gary Dudley co-authored the current study, explained that caffeine likely works by blocking the body’s receptors for adenosine, a chemical released in response to inflammation.

Despite the positive findings in the study, the researchers say there are some caveats. First, the results may not be applicable to regular caffeine users, since they may be less sensitive to caffeine’s effect. The researchers chose to study women to get a definitive answer in at least one sex, but men may respond differently to caffeine. And the small sample size of nine volunteers means that the study will have to be replicated with a larger study.

O’Connor said that despite these limitations, caffeine appears to be more effective in relieving post-workout muscle pain than several commonly used drugs. Previous studies have found that the pain reliever naproxen (the active ingredient in Aleve) produced a 30 percent reduction in soreness. Aspirin produced a 25 percent reduction, and ibuprofen has produced inconsistent results.

“A lot of times what people use for muscle pain is aspirin or ibuprofen, but caffeine seems to work better than those drugs, at least among women whose daily caffeine consumption is low,” O’Connor said.

Still, the researchers recommend that people use caution when using caffeine before a workout. For some people, too much caffeine can produce side effects such as jitteriness, heart palpitations and sleep disturbances.

“It can reduce pain,” Maridakis said, “but you have to apply some common sense and not go overboard.”

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Article adapted by MD Only Sports Weblog from original press release.
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Contact: Sam Fahmy
University of Georgia

The serious athlete knows better than to rely just on a famous cereal to provide additional energy in preparation of a sporting event. Supplements have assumed an important role in today’s training regimen. Some – such as anabolic steroids — have been deemed illegal by most sports authorities. Others – such as caffeine and creatine — are controversial yet presently allowed.Background
Caffeine, the primary ingredient of coffee, is used as a central nervous system stimulant, diuretic, circulatory and respiratory stimulant, and as an adjunct in the treatment of headaches. Evidence shows that caffeine intensifies muscle contractions, masks the discomfort of physical exertion, and even speeds up the use of the muscles’ short-term fuel stores. Some exercise physiologists believe that caffeine might improve performance by increasing fat oxidation and conserving muscle glycogen.

Creatine is used by athletes to increase lean body mass and improve performance in single and repetitive high-intensity, short-duration exercise tasks such as weightlifting, sprinting, and cycling. It is a popular nutritional supplement that is used by physically active people – from recreational exercisers to Olympic and professional athletes. According to a recent survey, 28 percent of athletes in an NCAA Division IA program reported using creatine. The creatine that is normally present in human muscle may come from two potential sources: dietary (animal flesh) and internally manufactured.

The purpose of creatine supplementation is to increase either total creatine stores or phosphocreatine (PCr) stores within muscle. Supplementation increases the rate of resynthesis of creatine phosphate following exercise. Various studies have shown increased muscle PCr levels after supplementing with 20-30 grams of creatine monohydrate daily.

Creatine supplementation has also been known to shorten relaxation time during intermittent maximal iosometric muscle contraction. This shortened time, coupled with a creatine loaded muscle facilitates calcium absorption into the sarcoplasmic reticulum (the endoplasmic reticulum of skeletal and cardiac muscle). However, some believe that caffeine intake enhances calcium release from the sarcoplasmic reticulum.

The Study
This has lead a research team from Belgium to suggest that the combined effects of creatine and caffeine supplementation may be counterproductive to creatine’s effect on muscle relaxation time. The authors of the study, “Opposite Actions of Caffeine and Creatine on Muscle Relaxation Time in Humans” are P. Hespel, B. Op ‘T Eijnde, and M. Van Leemputte, all from the Department of Kinesiology, Katholieke Universiteit Leuven, Leuven, Belgium. Their findings appear in the February 2002 edition of the Journal of Applied Physiology.

Methodology
Ten physical education students (nine men and one woman) participated in the study. They were told to abstain from medication and caffeine intake one week prior to the experiment. The subjects were additionally asked to avoid changes in their level of physical activity and diet during the 25-week duration of the study. In this double blind experiment, the subjects performed the exercise test before and after creatine supplementation, short-term caffeine intake, creatine supplementation in the short term, acute caffeine intake, or a placebo.

This study required the random assignment of the students into five experimental protocols, each lasting eight days. Three elements were measured during an experiment consisting of 30 intermittent contractions of quadriceps entailing two seconds of stimulation and two seconds of rest. Measurements included maximum torque (Tmax), contraction time (CT) from 0.25 to 0.75 of Tmax, and relaxation time (RT) from 0.75 to 0.25 of max.

Results
Key findings of this study included:

· a confirmation of the fact that oral creatine supplementation shortens muscle relaxation time in humans: relation time was reduced by five percent and was significantly shorter than after the placebo;

· discovery that the intake of caffeine, combined with a daily creatine supplement, counteracted the beneficial effects of creatine intake on relaxation time and fatigue enhanced this inhibitory effect; and

· the observation that caffeine reduces the functional capacity of sacroplasmic reticulum calcium ATPase.

Conclusion The researchers believe that the findings from this experiment offer indirect evidence that suggests that facilitation of muscle relaxation may be important to the ergogenic action of creatine supplementation as well as power production during sprint exercises.

However, for the athlete in training, the key finding is that sustained caffeine intake, over a three-day period, negates the benefits of creatine supplements.

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Article adapted by MD Only Sports Weblog from original press release.
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Contact: Donna Krupa
American Physiological Society

The majority of non-medical anabolic-androgenic steroid (AAS) users are not cheating athletes or risk-taking teenagers. According to a recent survey, containing the largest sample to date and published in the online open access publication, Journal of the International Society of Sports Nutrition, the typical male user is about 30 years old, well-educated, and earning an above-average income in a white-collar occupation. The majority did not use steroids during adolescence and were not motivated by athletic competition or sports performance.

The study, conducted by a collaboration of researchers from around the country coordinated by Jason Cohen, Psy.D. candidate, used a web-based survey of nearly 2,000 US males. Whereas athletes are tempted to take anabolic steroids to improve sports performance, the study suggests that physical self-improvement motivates the unrecognized majority of non-medical AAS users who particularly want to increase muscle mass, strength, and physical attractiveness. Other significant but less highly ranked factors included increased confidence, decreased fat, improved mood and attraction of sexual partners.

Although often considered similar to abusers of narcotics and other illicit drugs (e.g., heroin or cocaine), non-medical AAS users are remarkably different. These users follow carefully planned drug regimens in conjunction with a healthy diet, ancillary drugs and exercise. As opposed to the spontaneous and haphazard approach seen in abusers of psychotropic drugs, everything is strategically planned to maximize benefits and minimize harm. “This is simply not a style or pattern of use we typically see when we examine substance abuse” said Jack Darkes, Ph.D., one of the authors. “The notions of spontaneous drug seeking and loss of control do not apply to the vast majority of AAS users,” added co-author Daniel Gwartney, M.D.

“These findings question commonly held views of typical AAS users and their underlying motivations,” said Rick Collins, one of the study’s authors. “The focus on ‘cheating’ athletes and at risk youth has led to irrelevant policy as it relates to the predominant group of non-medical AAS users. The vast majority of AAS users are not athletes and hence, are not likely to view themselves as cheaters. The targeting of athletes through drug testing and other adolescent or sports-based interventions has no bearing on non-competitive adult users.” The study concludes that these AAS users are a driven and ambitious group dedicated to gym attendance, diet, occupational goals and educational attainment. “The users we surveyed consider that they are using directed drug technology as one part of a strategy for physical self-improvement within a health-centered lifestyle,” said Collins. “Effective public policy should begin by accurately identifying who’s using steroids and why. We hope our research – the largest adult survey of non-medical AAS use we know of – is a significant step forward in that direction.”

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Article adapted by MD Only Sports Weblog from original press release.
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Contact: Charlotte Webber
BioMed Central

Article:
A League of Their Own: Demographics, Motivations and Patterns of Use of 1,955 Male Adult Non-Medical Anabolic Steroid Users in the United States
Jason Cohen, Rick Collins, Jack Darkes and Dan Gwartney
Journal of the International Society of Sports Nutrition (in press)

During embargo, article available at: http://www.jissn.com/imedia/1374735248154681_article.pdf?random=454689

After the embargo, article available from the journal website at: http://www.jissn.com

Use of growth hormone to boost athletic performance can lead to diabetes, reports a study published ahead of print in the British Journal of Sports Medicine.

The study reports the case of a 36 year old professional body-builder who required emergency care for chest pain.

He had lost 40 kg in 12 months, during which he had also experienced excessive urination, thirst, and appetite.

He admitted to using anabolic steroids for 15 years and artificial growth hormone for the past three. He had also taken insulin, a year after starting on the growth hormone.

This was done to counter the effects of high blood sugar, but he had stopped taking it after a couple of episodes of acute low blood sugar (hypoglycaemia) while at the gym.

Tests revealed that his liver was inflamed, his kidneys were enlarged and that he had very high blood sugar. He was also dehydrated, and diagnosed with diabetes.

He was given intravenous fluids and gradually increasing amounts of insulin over five days, after which he was discharged. His symptoms completely cleared up, and he was no longer diabetic.

The use of growth hormone has steadily risen among amateur athletes and bodybuilders all round the world, say the authors, because it is easy to buy online and difficult to detect in screening tests—unlike anabolic steroids.

The authors believe that this is the first reported case of diabetes associated with the use of high dose growth hormone, and urge anyone taking high doses to regularly check their blood sugar levels.

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Article adapted by MD Only Sports Weblog from original press release.
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Contact: Emma Dickinson
BMJ Specialty Journals

Adolescents who don’t get enough sleep might be jeopardizing their athletic performance, and high school sports teams on the west coast may be at a disadvantage if they play east coast rivals, says Mary Carskadon, PhD, of the Bradley Hasbro Children’s Research Center.Carskadon, a leader in the field of sleep research, compared the results of studies that measured sleep patterns and circadian rhythms in children and adolescents in the May 24 issue of Clinics in Sports Medicine. While it’s widely known that lack of sleep can affect learning, mood and behavior in teenagers, Carskadon suggests that insufficient sleep can also negatively impact teen athletes in a number of ways.

“Young people live in nearly a constant state of chronic insufficient sleep,” says Carskadon, “and adolescents who don’t get enough sleep on a regular basis are extremely impaired in the morning.”

For this reason, she suggests that adolescent travel teams heading westward across time zones have an advantage over home teams early in the day.

While most adults who routinely travel from coast to coast might be well aware of the difficulty adjusting to a different time zone, teens are at even more of a disadvantage.

Evidence suggests that the adolescent circadian rhythm, or internal biological clock, is still adjusting, and their internal day-length is longer than that of adults. This means that teens might not be ready to fall asleep until later in the evening, or may wake up later in the morning.

“For morning games, the home team might still be in the lowest point of alertness,’ while the team that headed west will have the advantage of having been awake for an hour or so longer, and thus have more energy.”

Additionally, if the eastern team arrives the night before, they would gain an extra hour or two of sleep, which can improve focus, alertness, and better reaction skills.

Conversely, she warns that athletic teams taking extended training trips (eg. spring break) of a week or more may experience schedule difficulties on the return home.

“This scenario is most problematic for teams on the east coast that travel west, as student athletes may return with a significant sleep-phase delay that is difficult to correct,” Carskadon says.

Lack of sleep doesn’t just affect athletics in teenagers. Studies repeatedly show that reaction time, vigilance, learning and alertness are impaired by insufficient sleep; so students with short nights and irregular sleep patterns perform poorly in school and in other aspects of their life and have a tendency for a depressed mood.

“Circadian and lifestyle changes conspire to place sleep of adolescents at a markedly delayed time relative to younger children and to adults,” says Carskadon.

In fact, studies have shown that teenagers need as much, if not more sleep as younger children (an average of 9.25 hours per night) but as they mature, their bodies are able to stay alert later into the night.

She cites part-time jobs, caffeinated beverages, social activities, away-games and long practices as factors that help contribute to chronic sleep deprivation for young people.

Is there any reprieve? An afternoon nap can help, but only for so long. Carskadon found that a 45-minute nap taken approximately six hours after waking supported alertness and mood for about eight hours. For a teen who starts his day at 6:30 am, a lunchtime nap could keep him going till 8 or 9 pm.

However, Carskadon warns that afternoon naps don’t help morning fatigue the next day.

“In order to help adolescents do their best, parents need to take an active role in helping set a regular sleep pattern for their teen.”

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Article adapted by MD Only Sports Weblog from original press release.
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Contact: Carol L. Hoy
Lifespan

Mary Carskadon, PhD, directs the Bradley Hospital Sleep and Chronobiology Research Laboratory, and is a Professor of Psychiatry and Human Behavior at Brown Medical School in Providence, RI. She is currently recruiting children and young adults for several studies.

Founded in 1931 as the nation’s first psychiatric hospital for children, Bradley Hospital (www.bradleyhospital.org) remains a premier medical institution devoted exclusively to the research and treatment of childhood psychiatric illnesses. Bradley Hospital, located in Providence, RI, is an affiliate of Brown Medical School and ranks in the top third of private hospitals receiving funding from the National Institutes of Health. Its research arm, the Bradley Hasbro Children’s Research Center (BHCRC), brings together leading researchers in such topics as: autism, colic, childhood sleep patterns, HIV prevention, infant development, obesity, eating disorders, depression, obsessive-compulsive disorder (OCD) and juvenile firesetting. Bradley Hospital is a member of the Lifespan health system.