You might be sheltered from the elements, but is treadmill running easier than running outside? These cardio machines have been a staple in many runners' routines for decades, and for good reason. The best treadmills (opens in new tab) can provide you with a brilliant form of aerobic exercise, no matter the weather. Come rain or shine, this running machine can be used around the clock. We’ll be unpacking the science behind this convenient form of cardiovascular training.
According to the American Heart Association (opens in new tab), adults should be doing at least 150 minutes of moderate-intensity aerobic exercise a week to maintain good health. And whether you have your own treadmill or go to a gym, treadmills can help you get your aerobic running hit. As well as the advantages of treadmill running, we’ll be looking at the disadvantages of running on a treadmill and whether you need certain types of trainers for using this machine.
• Related: Best running headphones (opens in new tab)
What are the advantages of treadmill running?
With no uneven outside terrain to deal with or poor weather conditions, you’d expect treadmill running to be easier. And according to research by the University of Calgary (opens in new tab) running on a treadmill is easier than pounding the sidewalks outdoors in many ways.
Firstly, treadmills pass the ground beneath you, so runners ‘receive energy (opens in new tab) from the treadmill at foot contact’ and ‘impart energy (opens in new tab) to the belt at toe-off due to the propulsive forces of the foot’.
Secondly, nowadays many running belts on treadmills are crafted with cushioning, therefore running on this type of machine is technically easier – especially on your joints – as it absorbs the shock of your foot hitting the belt.
And thirdly, a 2012 study (opens in new tab), (opens in new tab) found that most runners run slower on a treadmill than they do overground, due to our perception of speeds being influenced by the machine. So it can feel easier treadmill running, due to us physically running slower without the influence of the outside environment around us.
But mentally, running on a treadmill might not be so easy. A 2016 study published in the International Journal of Environmental Research and Public Health (opens in new tab) confirmed that it’s easier to maintain attention when exercising outdoors, rather than indoors due to directed attention and social interactions.
What are the disadvantages of treadmill running?
Along with the lack of scenery you'd otherwise get by taking a run outside, the other most obvious disadvantage of treadmill running is the up-front cost for a gym membership or the money it will cost to invest in your own machine. What’s more, if you do end up buying your own treadmill, unlike outdoor running, you’ll also have to pay the added electricity costs to power the machine.
Physically speaking, treadmill running can cause some disadvantages. As stated by a report (opens in new tab) titled: 'Running head: Gait changes during treadmill running', it’s believed that running on a treadmill can very subtly change your natural running gait.
The report says: "While gait variables changes were found using the treadmill, many were very subtle and further examination of the data using effect sizes showed that the practical importance of some changes was minor."
The same report noted treadmill running showed an increased step length, decreased cadence, and an increase in flight time.
The report continued: "The changes in contact and flight times suggested athletes altered their gait so that more time was spent airborne to allow the treadmill to pass under them."
Along with your running form, a 2020 report (opens in new tab) discovered that your foot hits the ground differently when treadmill running and overground running, changing your running gait.
Do you need certain shoes for treadmill running?
Not necessarily. According to Runner’s World (opens in new tab), many runners tend to wear the same pair of shoes to run inside as they do to run outside.
That’s because of the softer surface belt treadmills have, compared to the often hard and natural outside terrain. Technically speaking, this means you could get away with wearing lighter, less cushioned trainers while running on a treadmill.
However, as highlighted by the American Podiatric Medical Association (opens in new tab), 'one of the first steps to healthy running is wearing supportive running shoes', whether you are running inside or outside. According to the Association, failure to do so could result in a variety of foot problems that can cause injury and impede performance.
To help find the best fitting trainers for your feet, it’s therefore important to understand whether you have a low or flat arch, normal arch or high arching foot.
As noted by the Association, feet with low arches need a supportive shoe to help correct pronation. Feet with normal arches should have cushioning to 'help absorb shock', while those with high arches should have a cushioned trainer that has a 'softer midsole' to help compensate for the high arches.