All over the world, children’s fitness and activity levels are declining. Image / 123RF
Today’s kids are less fit than previous generations, which wouldn’t put them well as adults in a warmer world. Written by Nikki Pellegrino.
The heat wave has continued through the European summer
affected people’s health. Extreme heat can lead to a host of stressful conditions, such as heat stroke, and as the body works extra hard to maintain its core temperature at normal levels, it puts a strain on the heart, lungs, and kidneys.
Higher temperatures increase the risk of heart disease and death, and studies have shown that the burden of heat-related heart attacks is likely to increase by 2-3°C of global warming. Therefore, as the planet warms, future generations will need to be physically fit and maintain optimal cardiovascular health if they are to thrive.
Unfortunately, the opposite happens, says Shonda Morrison, MD, a cardiovascular and environmental physiologist. Morrison completed her Ph.D. at the University of Otago and is now based in Slovenia, where she is involved in SLOfit, a longitudinal study of physical fitness and mobility for children.
“Every student in Slovenia takes the test once a year in April,” she says. “They do a bunch of fitness tests in physical education classes, so we have a lot of data.”
Children’s fitness and activity levels are declining around the world, with a 2018 report from the World Health Organization finding that 80 percent of 11-17-year-olds are not physically active enough. Evidence from SLOfit showed that this decline accelerated during the Covid-19 lockdowns.
“We found the largest decline in child fitness in the 30-year record from this longitudinal monitoring, and it was across the board — aerobic fitness, musculoskeletal flexibility, reaction time: all the different components.”
Families may have gone out for walks together in their neighborhoods during the lockdown, but the intensity of exercise the children were getting was not high enough to maintain fitness compared to the exercise that would have been provided by school physical education classes or organized sports.
Morrison, who works at the University of Ljubljana’s Faculty of Sports, wanted to delve deeper into the issue of fitness as global temperatures rise. In a review of more than 150 studies published in the journal Temperature, it found that children’s fitness was 30 percent lower than that of their parents of the same age.
In the research, she highlighted a study of 457 primary school-aged boys in Thailand that found that overweight young adults were twice as likely to have difficulty regulating their body temperature when exercising outdoors compared to those of normal weight.
Babies regulate temperature a little differently than adults. They sweat less and lose heat instead by increasing blood flow to the skin, a process that can require the heart to work harder. When they are physically fit, their hearts are stronger and able to pump more blood flow per beat, so their blood vessels will be more reactive and efficient, Morrison says. In addition, there is a greater chance that they will grow up to be active and fit adults who will be better able to tolerate higher temperatures.
“However, as the world warms, children are less fit than ever.”
How do we change things? Morrison has some ideas.
“We have to build our society around the concept that we need to move our bodies,” she says. “This includes mandatory physical education classes in every school that physical education teachers teach. Parents have a big role to play, especially with children aged 3-10. We need to make physical literacy a priority. If you know how to grab, run, jump, Swim and do basic movement patterns, you’ll enjoy the movement. If you don’t feel confident, you may be sedentary for the rest of your life.”
She recommends no more than one hour of screen time a day – meaning any screen – and practice what you preach. Morrison doesn’t own a smartphone, and even on those hot days this summer, she made sure her two young children had the chance to run in the relatively cold weather in the evening, and give them plenty of water to prevent dehydration.
She says New Zealand, with its great outdoors, is well positioned to make a positive difference to the fitness and health of our children’s future.
“But parents need to be very diligent in modeling the right behavior. And children should not have smartphones.”