As presented by Samantha Hanslo at the Bellville Athletics Club, February 2020.
Your genes can determine how your heart rate and blood pressure respond to exercise – and may act as an early warning of future problems with your heart or blood vessels – according to new research published in The Journal of Physiology.
When people exercise, their heart rate and blood pressure increase. However, the magnitude of this increase is different for different people. Previous research has shown that abnormally large increases in blood pressure during exercise makes it more likely that people will suffer from future high blood pressure. Therefore understanding why people react differently to exercise is important as this can help to identify risk factors and enable early monitoring or treatment of individuals at risk.
Until now it has not been known why the response to exercise varies between different people. This new research has found that genetic differences in receptors found in skeletal muscles can contribute to this different response. Receptors are groups of specialised cells that detect changes in the environment and cause some kind of response. The scientists identified that the presence of two common genetic mutations in receptors found in skeletal muscle led to higher blood pressure during exercise compared to people who did not have them, particularly in men.
The research conducted by the University of Guelph (Canada), involved measuring heart rate and blood pressure of 200 healthy young men and women before and during exercise, plus analysing their DNA for genetic risk factors.
If you’re up there in age and feel like you can coast as a couch potato, you may want to reconsider. A new study suggests, for the first time in women over age 70, that working up a sweat can reduce the influence one’s genes have on obesity.
The message from the study is that your genetic risk for obesity is not wholly deterministic. The choices we make in our life play a large role in our health.
The study also revealed that genetic associations on BMI were strongest in sedentary postmenopausal women and weakest in women who reported high levels of recreational physical activity.
The study is significant in that, up to this point, little had been known about the effect of obesity genes later in life, particularly whether genetic predisposition can be mitigated by healthy behaviors such as physical activity, the researchers note.
It’s also one of a growing number of studies highlighting the benefits of being physically active, especially as it pertains to healthy aging.
The study was published last month in the journal Menopause.
By analyzing reported physical activity levels over time in more than 11 000 American adults, Johns Hopkins Medicine researchers conclude that increasing physical activity to recommended levels over as few as six years in middle age is associated with a significantly decreased risk of heart failure, a condition that affects an estimated 5 million to 6 million Americans.
The same analysis found that as little as six years without physical activity in middle age was linked to an increased risk of the disorder.
Unlike a heart attack, in which heart muscle dies, heart failure is marked by a long-term, chronic inability of the heart to pump enough blood, or pump it hard enough, to bring needed oxygen to the body. The leading cause of hospitalizations in those over 65, the disorder’s risk factors include high blood pressure, high cholesterol, diabetes, smoking and family history.
Older adults are more likely to stick with a group exercise program if they can do it with people their own age, a new University of British Columbia study has found.
Working out with peers of the same gender doesn’t seem to make a difference – it’s the age that counts.
The study points to the importance of age-targeting, but perhaps not gender-targeting, when developing these programs. The researchers knew from earlier studies that older adults prefer to exercise within their own age group. Same-gender classes do not lead to greater adherence. This is significant, as it could free facilitators from the cost of providing separate classes for each gender unnecessarily.
Age and gender groupings weren’t the only strategies researchers used to try to strengthen participants’ commitment. Participants also received custom T-shirts that identified them as members of a group and were given opportunities to socialize over coffee following class. All of this together points to the power of social connections. If you set the environment up so participants feel a sense of connection or belonging with these other people, then they’re more likely to stick with it.
Older adults worldwide are less active than they should be.
The study appears in Health Psychology.
New regulations requiring certain female athletes to medically lower their testosterone levels in order to compete internationally are based on “fatally flawed” data, according to research led by the University of Colorado Boulder.
The research was published in the Asser International Sports Law Journal.
The authors have called for a retraction of the original research and asked the International Association of Athletics Federations – the global governing body for track and field – to reconsider the rule change, which affects
South African Olympic sprinter Caster Semenya and others.
“In almost any other setting of science, errors of this magnitude would lead to a paper being retracted,” said lead author Roger Pielke Jr., director of the Center for Sports Governance at CU Boulder. “And it certainly would not be the basis for broad regulations that have a profound impact on people’s lives.”
In April 2018, the IAAF announced new regulations requiring certain female athletes with naturally high testosterone levels to take testosterone-lowering hormones if they want to continue to compete in the women’s category for the 400-meter, the 400-meter hurdles, the 800-meter, the 1,500-meter and the mile.
The rule, which applies to IAAF-sanctioned international competitions, requires that they maintain serum testosterone levels below 5 nanomoles per liter (nmol/L) for at least six months prior to competition. Most females have testosterone levels ranging from 1.12 to 1.79 nmol/L while the normal adult male range is 7.7 – 29.4 nmol/L. About seven in every 1,000 elite female athletes have high testosterone levels, according to IAAF.
The association had attempted to put forth similar regulations in 2011 , but that rule was thrown out when the Swiss-based Court of Arbitration for Sport (CAS) – the highest court for international sport – concluded in 2015 that there was a lack of evidence linking high testosterone to “a real competitive advantage” in women.
In 2017, the IAAF came back with that research, publishing a paper in the British Journal of Sports Medicine (BJSM), which claimed that elite women runners with the highest testosterone levels performed as much as 3 percent better than those with the lowest levels in several events.
Pielke and co-authors Erik Boye, a professor emeritus of molecular biology at the University of Oslo, and Ross Tucker, a University of Cape Town exercise physiologist, challenge those results.
“We found problematic data throughout the study and consequently, the conclusions can’t be seen as reliable,” Pielke said.
When the three tried to replicate the original findings using data from the study’s authors and publicly available results from four of the races included, they uncovered “significant anomalies and errors.”
For instance, they found performance times that were erroneously duplicated and “phantom times” that did not exist in official IAAF competition results. In addition, some athletes disqualified for doping were included in the study dataset – a fact that could confound the results.
In all, from 17 to 32 percent of the data used in the study was found to be in error. The researchers also note that IAAF researchers themselves conducted the BJSM study.
“We would not find it appropriate for cigarette companies to provide the scientific bases for the regulation of smoking, or oil companies to provide the scientific bases for regulation of fossil fuels. Sport regulation should be held to the same high standards,” they write.
The IAAF researchers did correct what they characterized as “data capture errors” and re-ran their analysis in a subsequent letter to the journal. But flaws remain in that revision, Pielke said.
The research will be at issue later this month when Pielke is expected to serve as an expert witness at the Court of Arbitration for Sport, where Semenya and Athletics South Africa have brought a case against the IAAF calling the rules “discriminatory, irrational, and unjustifiable.”
Under the new regulations, those who decline to medically reduce their testosterone levels must relinquish their right to compete as females.
Originally set to take effect in November, implementation of the rules has been postponed until after the outcome of the case.
“Fundamentally, the issues that we raise with our paper are about the integrity of science in regulation,” said Pielke. “Any agency, in sport or beyond, should be expected to produce science that can withstand scrutiny and which actually supports the justification for proposed regulations. That simply did not happen here.”
(This information is based on current peer-reviewed research. I will update when there are new developments.)
As a runner, you should follow a healthy diet, not a fad diet. Also, take note that a runner’s nutritional needs are different from those of sedentary individuals. Long-distance running, and especially endurance running, increases the nutritional needs of the body. Ideally, you should have regular medical checkups to keep an eye on your nutrient levels.
Here are a few key areas of importance before a race.
Make sure you drink water every day. Your urine is a basic indicator. It should be light yellow.
To help improve nutrition you can add some chia seeds to your water. It is rich in omega-3 fatty acids, protein, iron, calcium, potassium, zinc, vitamins & antioxidants.
Salt is a key player in hydration. Salt losses vary greatly based on sweat rate, but many runners lose an average of one gram of sodium per litre of sweat. Hot and sweaty conditions make replenishing your fluids and sodium levels even more important. Add an extra sprinkle of salt to your dinner. Also, look for people offering something salty on the way. There will be something. You don’t need to carry salt.
Stick to your regular, healthy diet. Do not make big changes to your diet the weeks before the race. You should aim for about 5 – 8 grams of carbohydrates per kg of bodyweight per day, and 1 – 1.6 grams of protein.
Do not load your body with large amounts of carbs the night before the race. You might end up feeling bloated the next morning. Anxiety about the race can also impact digestion, adding to your discomfort.
You may want to add Rooibos tea to your diet at some point. It is a natural bronchodilator – helps you breath easier.
Tea made from Mullein flowers helps clear congestion in the lungs and soothes irritated mucous membranes. It is also an anti-inflammatory.
Ideally, your diet should be rich in all the essential nutrients. Have it checked from time to time. Your doctor will prescribe a supplement where necessary.
To make sure you arrive at your event well-prepared start taking a supplement 6 weeks before a major endurance event.
The key nutrients for runners are iron, vitamin B, magnesium, zinc and vitamin E.
Iron helps power a runner by providing the muscles with oxygen, without it the aerobic capacity is hampered and fatigue sets in prematurely.
The mineral is lost through sweat, and footstrike, which damages red blood cells in the feet. Vitamin C helps to retain the mineral in the body.
When you have your iron levels checked, also ask for a check on your ferritin levels. Ferritin is a protein that stores iron and releases it when needed. Ferritin binds with iron, keeping it from becoming a free radical in the body. Runners must have good ferritin levels.
Vitamin B keeps your nerve and blood cells healthy and plays a role in many metabolic processes that are directly related to running performance. A deficiency results in tiredness and weakness.
It is well known to runners that constant cramping of the legs is often an indicator of a lack of magnesium. Among the many biochemical functions it performs in the body, energy production is of special interest to us.
Zinc helps us process the carbohydrates, fats and proteins, and is vital for a healthy, high-performing immune system that will prevent you from getting sick. It also helps to kill bacteria and viruses should you become sick.
The longer distances you run, the more vitamin E you need. Intensified exertion brought on by high mileage produces more oxidative stress. Vitamin E is an antioxidant which helps guard cells from potential damage by combating oxidation.
One of the runner’s greatest fears is falling ill before a big race. Try to avoid contact with other people as much as possible the week before your race. Stay away from public places like movies or restaurants, and especially schools and hospitals.
Runners tend to turn to preventative medicine during this time. Because we can not always be sure of the effect of these supplements on our running you should try to stick to a natural nutritional supplement which is known to be easy on the stomach. Examples are Echinaforce and Bio-Strath.
A study published in the European Journal of Applied Physiology found that consuming probiotics helps in preventing stomach problems during endurance distances. Unfortunately, probiotic supplements aren’t closely regulated, which is why it is probably better to include foods like yoghurt or sauerkraut in your diet leading up to your race.
A positive attitude is an extremely important objective throughout your training. Try to put aside your unsubstained doubts and concentrate on your strengths.
When preparing for a race, visualize your approach. What will you do at a hill? How will spend your time at water tables? How will you finish?
Sleep as much as possible the week before your race – at least eight hours per night. The night before a race is often stressful, resulting in less sleep.
In the same vein; Netflix and chill is not of the menu the night before. Studies have shown that female athletes tend to perform better after a sexual encounter the night before. There is a slight, insignificant drop in performance for male athletes; there is no need for them to abstain from sex the night before.
Finally, focus on your positive experience. Nerves are normal, but take your positive training experiences to the start.
Various health practitioners agree that exercise is good for the heart — but the reasons why are still not well understood.
In a new study researchers from the Harvard Department of Stem Cell and Regenerative Biology (HSCRB), Massachusetts General Hospital (MGH) and Harvard Medical School (HMS), and the Harvard Stem Cell Institute (HSCI) uncovered one reason why exercise might be beneficial: it stimulates the heart to make new muscle cells, both under normal conditions and after a heart attack.
Published in Nature Communications, the findings have implications for public health, physical education and the rehabilitation of cardiac patients.
The human heart has a relatively low capacity to regenerate itself. Young adults can renew around 1% of their heart muscle cells every year, and that rate decreases with age. Considering that losing heart cells is linked to heart failure, interventions that increase new heart cell formation have potential to prevent heart failure.
The two senior authors behind the study were Richard Lee, M.D., Harvard Professor of Stem Cell and Regenerative Biology, and Principal Faculty member of HSCI, and Anthony Rosenzweig, M.D., Paul Dudley White Professor of Medicine at HMS, Chief of the Cardiology Division at MGH, and Principal Faculty member of HSCI.
“Maintaining a healthy heart requires balancing the loss of heart muscle cells due to injury or aging with the regeneration or birth of new heart muscle cells. Our study suggests exercise can help tip the balance in favor of regeneration,” said Rosenzweig.
“Our study shows that you might be able to make your heart younger by exercising more every day,” said Lee.