The humble push-up is often underrated when compared with racier forms of exercise, but the old faithful may pave the way to a longer life.
New research, from the University of Sydney, looking at more than 80,000 adults, compared different forms of exercise and found that those who did strength-based exercise just twice a week had a 23 per cent reduction in risk of premature death by any means, and a 31 per cent reduction in cancer-related death.
On the other hand, a reduced risk of cancer-related death did not apply to those who only met the WHO aerobic guidelines of 150 minutes a week and not the twice-weekly strength training recommendation (which was only introduced in 2010).
While strength training has received some attention lately for its important role in muscle maintenance, metabolism, bone density as we age and cognitive function there was "a gap in the literature".
"There was very, very little research looking at the association between participation in strength-promoting exercise and long-term outcomes related to mortality," said lead author Emmanuel Stamatakis from the School of Public Health and the Charles Perkins Centre.
For the study, published on Wednesday in the American Journal of Epidemiology, Stamatakis and his team looked at different types of strength-based exercise including using machines or free weights at the gym as well as bodyweight exercises – sit-ups, push-ups, pull-ups – that people can do from home.
On average, those who regularly participated in strength training, did two sessions a week totalling 50 to 60 minutes and the researchers adjusted for other "confounding" lifestyle factors such as diet and demographics.
"A very encouraging finding and a finding I'm very keen to promote more was that there was not much difference [between gym-based or home-based strength exercise], the association was pretty much the same," Stamatakis said.
It is an "important finding", Stamatakis says, because of how few people stick to the gym long-term.
"If you're someone who can exercise on your own, doing simple exercises at home is very easy to do," he said.
They also found that two strength sessions were enough to receive the benefits and that doing more than that did not lead to additional benefits.
"The main message from our study is that strength exercise is as important as aerobic physical activity," Stamatakis said. "The [WHO] guidelines are OK, but I think we need to put more effort into promoting them and making it clear they are as important as the generic aerobic guidelines."
Although many of us know the guidelines (at least the aerobic ones), we still struggle to meet them. Less than 50 per cent of Australian adults meet the aerobic recommendations and this figure jumps to 85 per cent if you add in at least two sessions of strength-promoting exercise a week.
While urban design modifications (adding in more walkways and bicycle lanes) are strongly recommended by public health experts as a way to address aerobic inactivity, by making incidental exercise easy, it is harder to do the same with strength-based activity.
There are increasing numbers of outdoor gyms in parks, which is a positive step, but Stamatakis suggests other solutions might involve delivering strength-training programs through preventive healthcare – "if such a thing exists, we know how neglected prevention is".
This could be prescribed through referral of high-risk people (inactive) by doctors to an exercise specialist. Another alternative is including education and technique training in school PE classes.
One way or another, we need to start thinking about solutions "to enable and empower the population to be more physically active in general", Stamatakis says, adding that no one form of exercise is better than another.
One study from earlier this year found that high-intensity interval training (HIIT) had the potential to regenerate mitochondrial cells and was thus linked with anti-ageing.
Stamatakis points out that uptake of HIIT is generally by younger and healthier people.
We need to consider the effect of promoting HIIT to those who are not fit and healthy, he says.
"The people who most need to get active is middle-aged people who are at imminent risk of developing cardiovascular disease and type 2 diabetes ... the processes have started already, so these people need physical exercise to slow down or reverse the processes hopefully," Stamatakis said. "So, in that demographic, how do you sell a very high-intensity form of exercise that for some people will make them feel sick and have consequences about whether they go back and do it again."
Studying forms of exercise in isolation provides "clues" about the health-enhancing benefits of the options that are out there, but there is no one form that is better than the other.
"It's not about trying to figure out what is the best and what is second-best,"Stamatakis said, "it doesn't exist. Whatever you can stick to long-term, that is the best."