Social media is full of advice about the best kind of exercise to do.
There are countless videos showing us how to burn the most calories, or achieve the fastest flexibility gains, and even get rid of "face fat".
So, which one of them is right — and is there a best way to stay fit?
When did exercise become a thing?
It wasn't until the mid-50s that the benefit of exercise was scientifically proven.
In London, an epidemiologist decided to study the difference in morbidity and mortality between double-decker bus drivers and conductors over the course of a year.
Bill Hayes, author of Sweat: A History of Exercise, explains the results:
"Those who just drove the bus and were sedentary had a much higher rate of mortality and morbidity than the conductors who hopped on and off the bus all day long and ran up and down the stairs of the double-decker buses."
In fact, the conductors had half as many heart attacks as the drivers.
But the desire to exercise goes way back — to the founding of the Olympic Games and athletic competitions in the eighth century BC.
"At that time, it was jogging, running, swimming, boxing, wrestling — not the kinds of exercise we do today, like cycling and aerobics," Mr Hayes says.
"Just getting the body moving was part of ancient Greek and Roman culture."
Get moving — that's all you need to do
At the most basic level, moving the body is what all medical professionals recommend today.
Preeya Alexander is a GP in Melbourne, and she says the benefits of exercise are wide-reaching. It can help with depression or improve sleep.
"It doesn't need to change the way you look to count," Dr Alexander says.
"It's about far more than kilograms, centimetres and dress sizes."
These are the Australian guidelines for adults when it comes to exercise:
"Be active on most (preferably all) days, to weekly total of: 2.5 to 5 hours of moderate activity or 1.25 to 2.5 hours of vigorous activity or an equivalent combination of both."
Moderate activity, as Dr Alexander explains, is "anything that's getting your heart rate up, you're a little bit breathless, a bit warm and sweaty".
"That's when we know that exercise is counting in terms of reducing your risk of things like type 2 diabetes, heart disease, stroke."
Her own exercise regime is relatively simple.
"All I really do is brisk walking and Pilates, and I hit the targets of exercise every week," Dr Alexander says.
"I predominantly exercise for my brain, to reduce my stress levels, to reduce my risk of cancer and heart disease. It's not very glamorous, but it counts and it works for me."
The best exercise is what works for you
Mr Hayes, who has researched and written about the history of exercise from the ancient Olympics to the fitness trends of today, says Jane Fonda is "one of the most important figures in the history of exercise" thanks to her workout videos from the early 80s.
"What was so important about the video was that it democratised exercise for women especially, but for women and men all around the world," he explains.
"You didn't have to join a gym, you could simply buy a videotape."
And Fonda's still on a mission to get every body to move, according to her paid partnership with H&M on Instagram.
"I think one of the fascinating things about the pandemic was we were all at home suddenly, and those of us who belonged to gyms had to go cold turkey and figure out home exercise routines," Mr Hayes says.
"So what was so new in the late 70s and early 80s sort of became the thing again during the pandemic."
But fitness trends come and go.
If leotards and leg warmers aren't for you, there's always something else — a team sport or a gym class, perhaps.
There are some specific exercises that are best for specific people.
For example, Dr Alexander recommends older patients do exercises that reduce the risk of falls.
"Do exercises which strengthen the muscles and improve balance," she explains.
"The other thing we should be thinking about as we age is weight-bearing exercise, basically, so that we don't have loss of density in the bones and you're trying to reduce the risk of osteoporosis."
But ultimately, she says, the best kind of exercise is whatever works for you.
"I say that to patients all the time — it's about what your body can manage, what is achievable for you day to day."
Mr Hayes adds that the best exercise should also be something you enjoy.
"There are so many different forms of exercise," he says.
"It doesn't have to be in the gym — you could be dancing in your apartment — as long as you're moving your body."
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