Category: Health

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Improve your running by cooling your body

12th August 2022 Quintus Van Rensburg 1 Comment Health, Marathon, Running technique

Experienced ultra-distance runners know that performance is improved by a reduction in body temperature. Or, cooling your body with water in the heat will make you run better. This practice has become a priority for long-distance runners.

Science has proved: that heat hurts endurance performance, even when it’s not very hot.

There are many studies on major marathons*. The findings agree that rising temperatures hurt performance – much earlier in a run than we realise. Reducing body temperature improves speed and is likely to reduce the effects on your health from ultra running.

How do we cool our bodies? Some of the following will give you an immediate advantage in your next race.

Keep your body wet, ideally with cold water. Don’t just drink at water stations. Spray yourself with the water. Focus on your head, neck, core and hamstrings. Male runners should tape their nipples securely. It may be loosened by water and become a bloody mess. When you wear compression socks, keep water away from them as they may pool water at your feet.

Light, reflective clothing keeps your skin surface temperature cool in extreme heat. Running vests are generally much better than shirts under extreme conditions.

Apply ice or water to your body using your clothing. Grab some ice at a water station and use your cap, buff, sleeves or pants to keep it near your skin. Stuff it wherever possible. You may have pockets you don’t use at some point. I use my buff to hold a broken water sachet on my head.

Apply cold water to your skin and head before the race on hot days. If core temperature increases in hot conditions, it is difficult to lower.

Remember to test the above in training to see what works for you.

* Studies were sourced from PLoS One, the International Journal of Environmental Research and Public Health, Sports Medicine and the British Journal of Sports Medicine – from 2010 to 2019

Strong coffee half an hour before running increases fat-burning

23rd February 2022 Quintus Van Rensburg No Comments Health, Supplements, Training

Scientists from the Department of Physiology of the University of Granada (UGR) have shown that caffeine (about 3 mg/kg, the equivalent of a strong coffee) ingested half an hour before aerobic exercise significantly increases the rate of fat-burning. They also found that if the exercise is performed in the afternoon, the effects of the caffeine are more marked than in the morning.

In their study, published in the Journal of the International Society of Sports Nutrition, the researchers aimed to determine whether caffeine–one of the most commonly-consumed ergogenic substances in the world to improve sports performance–actually does increase oxidation or “burning” of fat during exercise.

Maximum fat oxidation

The results of our study showed that acute caffeine ingestion 30 minutes before performing an aerobic exercise test increased maximum fat oxidation during exercise regardless of the time of day. The fat oxidation was higher in the afternoon than in the morning.

These results also show that caffeine increases fat oxidation during morning exercise in a similar way to that observed without caffeine intake in the afternoon.

In summary, the findings of this study suggest that the combination of acute caffeine intake and aerobic exercise performed at moderate intensity in the afternoon provides the optimal scenario for people seeking to increase fat-burning during physical exercise.

COVID-19 and the athletic heart

7th February 2022 Quintus Van Rensburg No Comments Health, Injury, Recovery

Reports have indicated that COVID-19 may cause heart damage in hospitalized patients with severe cases of the disease, but it’s unclear whether cardiac injury also occurs in infected patients who are asymptomatic or experience only mild symptoms. This question is of particular concern for athletes because myocarditis–inflammation in the heart usually caused by viral infection–can cause sudden cardiac death during exercise. In a special report published in JAMA Cardiology, a group led by sports cardiologists at Massachusetts General Hospital (MGH) and Emory University School of Medicine offers guidance for athletes’ return to play after they have recovered from COVID-19.

The researchers observed that athletes infected with COVID-19 who experienced no or mild symptoms did not exhibit signs of heart injury. For such athletes, they do not recommend detailed cardiac screening. The prevalence of cardiac injury in athletes who were infected with COVID-19 is still unknown, however, and the team believes it’s prudent to screen for heart damage in athletes with moderate to severe symptoms. The experts also note that despite recent small studies showing that cardiac magnetic resonance imaging has detected potential cardiac abnormalities in individuals who have recovered from COVID-19, they feel that current evidence doesn’t justify its use as a universal screening tool for athletes’ return to play.

Myocarditis

Want to turn back time? Try running a marathon

15th April 2021 Quintus Van Rensburg No Comments Health, Marathon

Research from the Journal of the American College of Cardiology suggests running a marathon for the first time could have several health benefits. The study found that for first-time marathon runners, training and completion of the marathon was associated with reductions in blood pressure and aortic stiffening in healthy participants that were equivalent to a four-year reduction in vascular age, with the greatest benefits seen in older, slower male marathon runners with higher baseline blood pressure.

Arterial stiffening is a normal part of aging, but it also increases cardiovascular risk in otherwise healthy individuals by contributing to increased pulse pressure and ventricular overload, which are associated with dementia and cardiovascular and kidney diseases, even in the absence of plaque in the arteries. While blood pressure medication can modify arterial stiffness in established heart disease, more cardiovascular events occur in individuals without diagnosed high blood pressure.

Regular aerobic exercise is a lifestyle modification that has real-world implications, particularly with the growth in mass participation running as an increasingly popular form of non-prescribed exercise.

The research found training decreased systolic and diastolic blood pressure by 4 and 3 mmHg, respectively. Overall, aortic stiffness reduced with training and was most pronounced in the distal aorta with increases in distensibility–the capacity to swell with pressure–of 9%. This amounted to the equivalent of an almost four-year reduction in ‘aortic age.’ Older patients had greater changes with exercise training, with males and those running slower marathon times deriving the greatest benefit.

The study shows it is possible to reverse the consequences of ageing on our blood vessels with real-world exercise in just six months. These benefits were observed in overall healthy individuals across a broad age range and their marathon times are suggestive of achievable exercise training in novice participants.

Although the study only recruited healthy participants, those with hypertension and stiffer arteries might be expected to have an even greater cardiovascular response to exercise training.

runner drinking drink water

Drink to thirst

20th January 2021 Quintus Van Rensburg No Comments Health, Supplements

Hyponatremia is a condition of low sodium concentration in the blood. Prolonged overhydration during exercise is the primary cause of all forms of exercise-associated hyponatremia (EAH) and should be avoided. The updated EAH clinical practice guidelines issued by the Wilderness Medical Society stress that individuals engaged in physical and endurance activities should drink to satisfy their thirst (known as “drink to thirst”) to avoid overhydration. The guidelines appear in Wilderness & Environmental Medicine, published by Elsevier.

Review articles and international consensus statements have mainly focused on the incidence of EAH in organized endurance events that are conducted in the frontcountry, where medical tents and local emergency medical services are typically available on site and transport to a local hospital is readily available. However, many prolonged individual exertional activities such as backpacking, ultramarathons, and multiple-day endurance events take place in the backcountry with limited or no medical support and expectations of delayed medical evacuation.

Appropriated management of EAH depends first on correctly diagnosing the condition. The guidelines address the assessment of patients with overlapping or nonspecific signs that can make differential diagnosis challenging, for example, with heat exhaustion or exertional heat stroke.

The guidelines recommend that:

  • Appropriate education and coordination among participants, event directors, support crews, park rangers, first responders, and EMS transport personnel are essential in both prevention and management of EAH.
  • Prolonged overhydration during exercise, which is the primary risk factor in the development of all forms of EAH, should be avoided.
  • Sodium and/or salty snacks should be freely available for consumption along with the appropriate fluids, particularly in long, hot events in non-heat acclimatized persons.
  • Participants should drink enough to satisfy their thirst but avoid overdrinking.
  • Point-of-care testing should be done on at-risk, symptomatic patients, when available.
  • Oral fluids should be restricted if EAH from fluid overload is associated with mild symptoms.
  • Hypotonic fluids are contraindicated with suspected EAH.
  • The use of oral salt or hypertonic fluids may be effective in reversing moderate to severe symptoms of EAH when no IV hypertonic saline (3 percent) is available.
  • Patients should be observed for at least 60 minutes after exercise to ensure no decompensation from delayed symptomatic EAH.
  • Receiving caregivers should be alerted to the potential diagnosis of EAH and fluid management restrictions when transferring care.

EAH is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe EAH being below 120 mEq/L. Symptoms may include nausea and vomiting, headache, short-term memory loss, confusion, and lethargy, altered mental status, coma, seizures, and/or respiratory distress, some of which can be confused with other medical conditions.

Staying fit can cut your risk of heart attack by half

24th August 2020 Quintus Van Rensburg No Comments Biomechanics, Health

Poor cardiorespiratory fitness could increase your risk of a future heart attack, even if you have no symptoms of a lifestyle illness today, a new study has found.

A strong link was found between higher fitness levels and a lower risk of heart attack and angina pectoris over the nine years following the measurements that were taken in a study by the Norwegian University of Science and Technology’s (NTNU) Cardiac Exercise Research Group (CERG).

The study results have been published in the European Heart Journal.

Even among people who seem to be healthy, the top 25 per cent of the fittest individuals actually have only half as high a risk as the least fit 25 per cent.

Between 2006 and 2008, CERG researchers measured the cardiorespiratory fitness of 4527 men and women who participated in the HUNT3 population-based health survey in Nord-Trøndelag. None of the subjects had cardiovascular disease, cancer or high blood pressure, and most were considered to be at low risk of cardiovascular disease for the next ten years.

Nevertheless, 147 of the participants experienced heart attacks or were diagnosed with angina pectoris by 2017. These diseases signal that the coronary arteries in the heart are narrowed or completely blocked.

The researchers analysed the participants in groups based on their level of fitness in relation to others of the same age and gender. The risk proved to decline steadily as patient fitness increased. The correlation between fitness and cardiovascular risk also held after adjusting for other factors that differed between the most and least fit participants.

One of the greatest strengths of the study is that the test used maximum oxygen uptake to measure participant fitness. Earlier studies that have linked fitness level to disease risk in healthy populations have largely been based on less precise calculations of fitness, or on self-reported physical activity information.

Our body uses oxygen to drive metabolic processes that create energy for the muscles. Maximum oxygen absorption is simply the maximum amount of oxygen the body is able to absorb during physical activity. Heart, blood vessel and muscle functioning are all important for oxygen uptake.

The study suggests that even a small increase in fitness can significantly improve health. For each increase of 3.5 fitness points, the risk of heart attack or angina decreases by 15 per cent.

Even if you never get in such good shape that you can say you have optimal protection, the study shows that participants’ risk was lower the more fit they were.

To measure maximum oxygen uptake accurately, you have to breathe into a mask while running on a treadmill, where the speed increases or the incline gets steeper every minute. As you work at higher and higher intensity, your body needs more and more oxygen. The test ends when you can’t run anymore, or when measurements show that the oxygen uptake is no longer increasing even though the treadmill speed is.

But why does the fitness number mean so much for your future health?

Researchers use a treadmill and a special mask to measure a person’s maximum oxygen uptake, which is considered an important measure of fitness.

Your genes determine how your heart rate responds to exercise

21st February 2020 Quintus Van Rensburg No Comments Health

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.

Exercise mitigates genetic effects of obesity later in life

23rd January 2020 Quintus Van Rensburg No Comments Health

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.

Change your risk for heart failure

22nd October 2019 Quintus Van Rensburg No Comments Health

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.