Fitness fact check: Which 2016 studies hold up to scrutiny?
Published Wednesday, December 28, 2016 7:00AM EST
We asked Canadian researchers to weigh in on some of 2016’s top fitness news. (Shutterstock.com)
Another year over, another year of being overwhelmed by fitness studies. How to make New Year’s resolutions when you don’t know whether you should work out vigorously for 10 minutes or moderately for an hour? Or whether that fitness tracker can help you reach your weight-loss goal?
To help make sense of it all, CTVNews.ca asked researchers at McMaster University’s Physical Activity Centre of Excellence (PACE) to weigh in on some of 2016’s top fitness news.
Consumer Reports released a study that tracked 800 adults and found that although most wore fitness trackers and logged 50,000 to 70,000 steps a week, none had lost weight or saw their blood pressure fall. About 90 per cent of the subjects stopped wearing the trackers.
Stuart Phillips, director of PACE and a professor of kinesiology, says devices are good at measuring calories burned but not calories consumed. Fitness trackers are a great reminder of the need to move but “exercise is not a magic bullet for weight loss.”
“Our ability to regulate the food we take in is surprisingly poor. And when fitness trackers measure what we’re doing, it can be seen as a licence to eat more. But one cupcake means that whole half hour on the treadmill is moot. Stop eating the cupcake and the effect is immediate.”
Fitness and intellect
A study out of the University of Regina found walking on a treadmill while studying improved both fitness and the absorption of information.
Phillips says this is an adaption of the idea of the walking meeting. Walking is not a brain-driven task, so it can be combined with simpler tasks, such as reading information that is easily understood.
“I like to wear a headset when I’m on a conference call because I feel I can think better while walking. But if you try to do a complex task while walking, it will fall apart. You wouldn’t want an air traffic controller walking around while landing a plane, for instance.”
But the intellectual link between fitness and cognitive performance is growing, says Phillips. Data continues to be compiled that shows children who perform well on treadmill tests also perform better on memory and algebra tests than children who underperform on the treadmill.
Anger and exertion
An international study that looked at 12,000 people who had had a first heart attack found that twice as many reported their heart attacks came within an hour of being emotionally upset or doing something physically strenuous. But if they were upset and did something strenuous right after, the chances of a heart attack tripled.
Phillips says this study should be read cautiously because the numbers of people having heart attacks overall was small. He said combining emotional arousal with physical activity in those not accustomed to exercise can be risky, but he points out that a sedentary lifestyle is much more dangerous.
The American Council on Exercise determined bouncing on a trampoline was as effective as running. Phillips says any form of activity that gets your heart rate up benefits health and his outings on his kids’ trampolines have shown him that bouncing is physically exerting.
“Getting people to exercise is a lot about choice. So this is a good news story because it offers an alternative to those who don’t like to run or find it hard on their joints.”
A study by a U.K. researcher found that one hour of exercise can counteract eight hours of sitting. Phillips says the greatest effect of being sedentary is an inability to handle blood sugar; a step toward Type 2 diabetes.
“Exercise creates a hole that you can fill in with a little bit of sugar. The main outcome of that trial is that an hour you do in the gym can undue a lot of the bad you do sitting around.”
If your job means sitting at a computer, Phillips recommends getting up from your desk to walk around the building or going up and down a few flights of stairs. “We’re only now beginning to appreciate what extended periods of sitting does to us. We still have the genes from when we needed to run around and forage and hunt for our food so our bodies are predisposed to hang on to weight… We must change our behaviour.”
The power of intervals
The No. 1 most-cited barrier to why people don’t exercise is lack of time.
McMaster researcher Martin Gibala’s work is showing that vigorous sprints of activity over 10 or 15 minutes has as much health benefit as extended but moderate exercise. That counteracts traditional public health guidelines that call for 150 minutes per week of continuous moderate exercise.
“I’m increasingly interested in the question: How low can you go?” says Gibala, a professor of kinesiology.
He says he’s continually amazed by the results that show the health benefits of intense, but short bursts of exercise. “Should everyone train this way? We’re not saying that. But surprisingly short bursts of exercise have great benefit. It’s a time efficient way to work out and there are lots of different types of interval training.”
Even gentle interval training – such as walking as fast as you can for the length of a couple of lamp posts during a walk around the block – shows benefit, says Gibala.
What motivates you to move? A study of 281 obese people showed that punishment, in the form of monetary fines, worked better than rewards, payment, in helping people achieve their exercise goals of 7,000 steps a day.
But Jennifer Heisz, who studies the connection between exercise and brain health and is associate director PACE, says external reward for exercise is not nearly as powerful as intrinsic reward, which are the internal positive feelings achieved through exercise.
So, in other words, promising yourself a new pair of shoes for reaching an exercise goal may work in the short term, but if you don’t make exercise enjoyable and rewarding in itself (listening to your favourite music, working out with someone you like being with, doing an activity that makes you happy), there won’t be long-term effects on your motivation.
“If you save up your favourite music to only listen to it while you exercise, you look forward to it and that positive feeling carries over to the activity and they become paired together. Over time, that develops into enjoyment of the activity. It’s like conditioning yourself but it requires hard work and dedication.”
Heisz also recommends scheduling your activity by putting it into your calendar because that is the first step to making it a habit.
The Canadian Society for Exercise Physiology released guidelines in June for children ages 5 to 17 that set the world’s first guidelines for activity, screen time and sleep.
“Looking at all three measures together gives a much better view of a child’s health,” said Brian Timmons, a professor in the pediatrics department at McMaster University. “It gives multiple measures for thinking of movement throughout the day.”
These guidelines call for at least 60 minutes per day of moderate to vigorous physical activity, no more than two hours a day of recreational screen time, limited sitting for extended periods and at least nine to 11 hours of sleep for children 5-13 years, and eight to 10 hours for those aged 14-17 years.
“A parent might have thought that if their child was making the physical activity guidelines that everything was fine. But if he’s on a screen five hours a day and only sleeping six hours a night, only looking at physical activity gives a false impression that things are fine.”
The Canadian Health Measures Survey released in November found that in a national sample of children, 17 per cent of kids met all three 24-Hour Movement components but even meeting just one translated into positive health outcomes.
As adults and kids took to the streets to digitally hunt Pokemon, there was plenty of talk about how the game was getting people active. In fact, Microsoft Research said the game got people of all ages and fitness levels moving more and could have added 2.83 million years of life expectancy.
The game may have boosted activity, for a while, says Timmons, but the effects are never enduring.
“You remember the Nintendo Wii? Did it get people up and moving? Yes. But does it lead to them remaining active for years? Not likely.”
Games and fads won’t do that, only building activity into daily lives will achieve it, says Timmons.
“Only when it’s OK to play at recess or that parents let their kids walk to school or play in the neighbourhood will those habits be formed. It’s about building an environment that allows activity and fundamentally changing behaviour.”