Is it safe? What experts say about heatwaves, heat stroke and how to exercise safely
Sixty-one-year-old Ballarat runner David Fraser’s weekly training regime includes four morning gym sessions and five trail runs ranging from 10km to 33km.
The situation is no different in the summer months when the temperature increases.
“It’s rare to change any of the routines during the summer; by keeping them the same, the body learns to adapt to conditions from very cold to extremely hot,” she says.
“The only time things might change is when there is lightning or very dangerous winds.”
While Fraser says she enjoys exercising in the heat and hasn’t experienced any serious side effects, noting that her only issue is occasional muscle cramps from sodium loss, how safe is it to continue your normal exercise routine when it’s hot?
exercising in the heat
Sam Chalmers, senior lecturer in human movement at the University of Adelaide, says that while the body has strategies to increase core heat loss during exercise at average temperatures (such as increasing an individual’s rate of sweat and blood flow through their skin), stressful sport and exercise in hot and humid conditions can mean the body is unable to defend against significant increases in core temperature.
“This can mean that symptoms can range from relatively minor symptoms, such as headaches and feeling faint, to more serious problems, such as central nervous system dysfunction, loss of consciousness and organ damage,” he says.
President of the Royal Australian College of General Practitioners, Dr. It can also increase the risk of exercise-induced heat illness, which ranges from mild heat stress to heat exhaustion and, in severe cases, potentially fatal heat stroke, says Michael Wright.
“Symptoms of heat stress or heat exhaustion include dizziness, nausea, and fatigue. More serious symptoms, such as when a person becomes confused, collapses, or stops sweating despite the heat and tension, are signs of heatstroke and need immediate care.”
Who is more at risk?
Everyone can be affected by hot weather, but some are more vulnerable and may not feel well in low temperatures.
This includes adults over 65, pregnant women, children and infants, as well as people who cannot regulate their temperature, “such as those with chronic health conditions such as heart, lung, kidney disease and diabetes,” Wright said.
Exercising in a heatwave
A heat wave, generally defined as three or more days in which maximum and minimum temperatures are unusually high, can exacerbate the effects of high temperatures. In this scenario, Wright recommends avoiding outdoor exercise altogether.
“Sometimes skipping or postponing exercise is the safest option,” he says.
Sydney-based runner and exercise physiologist Veronika Larisova prefers early morning or late evening sessions to avoid extreme heat.
“I’m changing my routine because I love being outside, but I don’t like running in the middle of the day or early afternoon in extreme heat,” she says.
“In addition to being uncomfortable, extreme heat places additional stress on the cardiovascular system and thermoregulation, so it is not always appropriate or safe to maintain the same intensity, duration, or timing throughout the year.”
Larisova says she has also reduced the intensity of her workouts and changed the exercises she does when temperatures rise.
“When I only have time to exercise during my lunch break and the day is very hot, I usually [Bondi] “Do a run-swim session on the Icebergs or Clovelly,” he says.
“Consistency over time is more important than a single session.”
Could there be benefits to exercising in the heat?
While it’s best to avoid certain exercises during a heatwave, Chalmers says there can be benefits to exercising on independent days of warm weather, if done safely.
“Regular exercise in the heat will result in the process of heat acclimation, which is a series of physiological adaptations that increase tolerance to heat,” he says.
“These may include increases in sweat rate, increased blood flow through the skin, greater body fluid volume, a lower heart rate at the same exercise intensity, and a general perception of feeling more comfortable in the heat.”
Not only has Fraser experienced this, but she says it’s been beneficial in other ways, too.
“My wife, who is a running coach, always told me that running in the heat is the equivalent of doing altitude training, the blood volume in your body increases and your heart starts pumping more efficiently, which increases the oxygen to your muscles,” he says.
“Your mental strength improves, and you finally get a huge endorphin boost after finishing a hot, sweat-soaked run.”
Experts agree Gradual exposure to warmer conditions can help your body acclimatebut they warn against it during heat waves.
How can you exercise safely in the heat?
If you choose to exercise in the heat, Sports Medicine Australia (SMA) CEO Jamie Crain says planning and preparation are key to exercising safely.
“Drinking plenty of water before exercise, it’s important to do this, make sure you have access to water during exercise and of course take breaks if you need to, make sure you have access to shelter or shade and adjust your clothing. [to lightweight, breathable fabrics] “If it’s appropriate,” he says.
Crain recommends using: Sports Heat Vehicle- It was developed by the SMA and the University of Sydney Heat and Health Research Center to evaluate heat-related risk factors in individuals during their respective sports.
“Internal heat production and levels of clothing or protective equipment (which prevent heat loss) vary significantly by sport. Duration of exposure is also highly dependent on the sport,” explains Professor Ollie Jay, academic director of the Center for Heat and Health Research.
“Our tool combines all of these factors with local weather information using a physiological model to predict heat stress risk for more than 40 individual sports.”
Chalmers also recommends this tool because different sports have different risk profiles depending on factors such as intensity and environment.
“Activities with more intense exercise and fewer breaks are generally riskier than activities with lower exercise intensity and more breaks,” he says.
“The heat risk tool can be used to make decisions about when and how hard you may want to exercise and when additional cooling strategies may be needed.”
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