Exercist Therapy: A Natural Anti-Depressant

By Abby Larson

Have you ever felt sad or stressed, laced up your running shoes and went on a run to find yourself feeling happier once you got back?  Anti-depressants might not be the best treatment for depression and anxiety, conditions that many Americans take drugs for.  Psychology Professors Smits and Otto from Southern Methodist and Boston Universities have shown that Exercise Therapy is a successful treatment of many mental health problems.
Presenting their findings at the Anxiety Disorder Association of America’s annual conference in March to researchers and mental health care providers, Smits and Otto have found that people who exercise show fewer signs of depression and stress.  Much like an anti-depressant, exercise triggers the release of neurotransmitters in the brain that help relieve stress and depression and allow patients to perform daily tasks more efficiently.  Additionally, as one exercises more, resting heart rate lowers, causing patients to feel less anxiety.
Smits believes that patients should exercise at least 150 minutes a week at a moderate-intensity or 75 minutes at high-intensity.  Exercise therapy is about the immediate benefits of exercise on mood, not just the long-term health benefits.
As the list of learned health benefits of exercise grows, psychiatrists should be encouraged to prescribe schedules and goals to exercise instead of anti-depressants for a less costly and more beneficial therapy for mood disorders.  So, next time you’re stressed about work or academics or have a loss of confidence, get outside and exercise.  It’s what the doctor ordered.

For more information, see links at SMU research

No Time to Exercise? Think Again

By Abby Larson

Not having enough time is no longer an excuse to avoid exercising.  Scientists at McMaster University in Canada published a study in The Journal of Physiology on short term high-intensity interval training (HIT), which consists of a series of short bursts of intense exercise with short recovery breaks in between.  They found that HIT works as well in building muscle and improving oxygen delivery to muscles as long term exercise.

The study, headed by Professor Martin Gibala, was performed on college students on a stationary bike with a workload at about 95% maximum heart rate.  Gibala found that doing 10 one-minute sprints on the stationary bike with one minute of rest in between resulted in the same physical benefits as long duration endurance biking.  This means that the muscular benefits of exercise can be achieved with less time and less exercise.  However, long-term exercise is still necessary for weight loss to maximize calories burned, but short-term, high intensity exercise is far more beneficial that no exercise at all.

The reasons behind these results are not yet known, but Gibala found that HIT activates some of the cellular pathways that are associated with producing the health benefits from endurance training.

These findings are not just for athletes trying to get into shape.  The scientists at McMaster think that a less “all-out” HIT method can be beneficial for people who require the benefits of exercise but are not advised to exercise for prolonged periods of time.  The team’s future research will examine the effects of HIT on the elderly, obese, and people with metabolic diseases such as diabetes.

So next time you only have 10-20 minutes to exercise, hop on a stationary bike to try this time-efficient and effective form of exercise.   Remember, though, that exercise plans should be catered towards an individual’s fitness goals.

Kicking it to good health

By Abby Larson
Photo from the study of women and soccer. Credit: Mikal Schlosser

In European countries, soccer is not just a sport; it’s a lifestyle. Now, soccer has joined the side of science.

Led by Professors Peter Krustrup and Jens Bangsbo at the University of Copenhagen’s Department of Exercise and Sports Sciences, over 50 researchers from 7 countries are finding out the benefits of soccer from a physical, psychological, and social perspective. Numerous articles will be published in the Scandinavian Journal of Medicine and Science in Sports on the effects of soccer on bone mass and bone density, standing postural balance, and muscle strength.   All of these can help reduce falls and bone fractures, especially in the elderly.

One of the studies had women aged 20-47 play soccer twice a week for 14 weeks. At the end of the time period, their leg bones and muscles were significantly denser and stronger. The same women, having never played soccer before, participated in a long term 16-week study showing that whole body bone mineral density was increased. The short and long-term effects found were higher than a similar study on the effects of running on bone and muscle mass. This is due to the combination of sprinting, long distance running, and high forces that act on the legs when cutting in soccer.

The benefits of soccer are not just for the young and middle aged. A study performed by the researchers showed that men in their 70s who have played recreational soccer most of their lives have much better muscle strength and balance than men of the same age who do not play soccer. They even had equal muscle strength and balance compared to untrained men in their 30s.

This cohort of studies can benefit men and women of all ages. The immediate effects of soccer may be beneficial to women going through menopause at risk for osteoporosis, since it quickly adds bone mineral density to the legs and improves balance. It can prevent falls and fractures in elderly men and women because it increases muscle mass and balance, especially in people who play soccer all their lives.

Funding for the projects comes from FIFA—Medical Assessment and Research Centre (F-MARC), The Danish Ministry of Culture, TrygFonden, United Federation of Danish Workers (3F), The Danish Football Association, Team Denmark and The Danish Sports Confederation. Future studies by Krustrup and Bangsbo include the effects of soccer on patients with diabetis and cancer, long-term effects on osteoporosis, and the cardiovascular and musculoskeletal effects on kids in youth soccer.

Where can I get that gene “juice”?

By Abby Larson

Athletes are competitive by nature, and many will do whatever they can to win.  Steroid usage is heavily monitored in competitions, yet with the coming of the Winter Olympics, whispers of “gene doping” are becoming audible. There has been a craze by athletes for “gene juice” ever since a 2005 study performed by Dr. Ronald Evans, a geneticist at the Salk Institute for Biological Studies in San Diego, California, produced the “Marathon Mouse”.  Evans discovered a gene involved in muscle formation and altered it, producing a mouse that could run twice as far as normal mice.  This spurred the World Anti-Doping Agency (WADA) to list gene doping as illegal.

Evans was searching for a way to treat muscular dystrophy, characterized by muscle wasting and inability to build muscle.  His study was based on the idea of gene therapy: treating a disease caused by a mutated or malfunctioning gene by inserting copies of the normal gene into cells.  The cells essentially replace the non-functional gene with the normal one.  So, if you can use gene therapy to treat mutated genes, why can’t you use gene therapy to replace a “normal” athletic gene with a “high performance” athletic gene?

A review article by Dr. Craig Sharp that will be published in March, 2010, titled “The Human Genome and Sport, Including Epigenetics, Gene Doping, and Athleticogenomics,” discusses many athletic performance gene discoveries that may be possible targets for gene doping.   One example is a gene encoding myostatin, an inhibitor of muscle growth.  Exercise tears muscles, which results in increased expression of actin and myosin.  This increase in expression is eventually repressed by the protein myostatin, preventing excessive muscle growth.  In 2004, a boy was born with a mutated form of myostatin that disrupted some of the protein’s function.  The boy had significantly hypertrophied muscles, and was still unusually muscular at age 4.  Based on studies like this one, by injecting muscle cells with the mutated form of myostatin, Sharp believes that athletes and bodybuilders can create greater muscle mass than without the gene doping because inhibition of muscle production will be decreased following exercise.  Who knew genetic studies could lead to Schwarzenegger-sized people?

Death does not seem to scare overzealous coaches and athletes, who may bypass the risks of gene doping to achieve that extra edge.  In several gene therapy studies, some patients developed cancers or severe autoimmune responses to the product of the injected genes.  A 2008 report by Dr. E.B. Wheeldon showed that a patient went into an extreme immune response due to a reaction with a carrier virus used to transmit the gene of interest into his cells, causing death from organ failure.  This does not seem to discourage some athletes and coaches.

Have athletes started using gene doping to get ahead?  An experimental drug, Repoxygen, was developed to treat severe anemia due to a mutated gene.  As several Olympic coaches discovered, Repoxygen contained the gene for erythropoietin (EPO), which increases red blood cell production and performance.  EPO itself is a currently banned substance by WADA for performance enhancement—but how can one detect the gene for it?  There are no current established methods for gene doping detection aside from muscle biopsy, says Sharp, which is a painful and unappealing method of detecting changes in tissue development.  A rising technique commonly used in cancer genomics may be the key: DNA microarray.  A DNA microarray detects changes in gene expression in a person between two periods in time.  In order for anti-doping agencies to use this method in top competitions such as the Olympics, an athlete’s genetic file must be established as a reference.  WADA has already developed a “passport” program to keep blood and urine samples of athletes on file to use for future genomic comparisons.

Gene doping raises an ethical issue that surpasses steroid use due to its difficulty in detection, although gene doping has been banned for over 5 years for major competitions.  By the 2012 Summer Olympics in London, genetic testing could be a common procedure by anti-doping committees.  It seems that as we learn more about the way the body responds to exercise and why the world’s top athletes are so good, more daemons are unleashed from Pandora’s box.

Abby Larson

Abby Larson is a senior biology major at Dickinson College with a focus in pre-medical studies.  She is a member of the Dickinson Women’s Lacrosse team and is highly involved in other activities on campus, including Delta Nu and the Student Athlete Advisory Committee.  Her involvement on the lacrosse team along with her major in biology has led her to be interested in exercise science, and she is pursuing her interests in a year after graduation through a medical or graduate degree.

Running in Genes

By Abby Larson

Can someone really be born to be an athlete?  Science says so.  The idea of a genetic basis to exercise is a fairly new area of science, but it makes sense based on how the human body works. The expression of genes controls the function of human physiology: muscle development, capillary growth, hemoglobin concentration in red blood cells, etc.   After strenuous exercise, gene expression fires up to control muscle tissue repair due to increased forces on the body and tissue metabolic demand.  Capillaries feeding the muscles grow and become more efficient at delivering oxygen to tissues.  All of this is controlled by gene expression, the cellular switchboard of the human body.

Recent studies have identified over 200 genes that can determine the body’s ability to adapt quickly to exercise.  Based on this, training and conditioning could only take an athlete up to his or her genetically predetermined potential.  Does this mean that children can be genetically tested to see if they will be good at sports?  Is there a gene that makes a good football player versus a good runner? It’s more complicated than saying if a person has a specific gene, he or she can be a top athlete.  Like all processes in the human body, multiple genes are involved in adaptation to exercise and gene interactions play a large role.   Gene products don’t interact in a linear fashion, but in pathways and networks.  This makes genes harder to understand, and our knowledge of the interactions is in its infancy.  Once these pathways are discovered, scientists can begin to understand the extent to genetic determination of athletic ability.

These studies on the genetic basis of exercise are not going to benefit  just athletes—physical activity is one of the greatest preventative medicines for obesity, diabetes, and heart disease.  It is likely that genes correlated with exercise response could be mutated in people that have obesity or heart disease, which proposes new options of drug and gene therapy as preventative medicine.  The more we understand the benefits and mechanisms of exercise, the better we can understand how exercise can be used to improve public health.  So next time you go to the gym or run outside, think to yourself, “this is science.”

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