The best thing about treadmill aerobic exercises is you can do them under any weather element. So whether it's rainy, snowy, or sun high, running indoors will get you closer to your fitness goals. But why do I run slower on a treadmill?
Running outdoors is unpredictable, and the terrain changes with every stride. In addition, you can run against the wind, making you cool down or have wind assist. All these changes make it challenging to determine which form is faster.
What Do the Records Say?
But let's compare the half marathon treadmill time and the half marathon record time outdoors. The fastest time over the half marathon distance (13.1 miles) is 57:31.
The fastest time over the half marathon distance on a treadmill is 1:10:07. According to a 2015 study by Biology of Sport Journal, treadmill runners don't have air resistance when running at the same velocity as outdoor runners. This makes indoor runners gain a better running economy. But with a slight 1% treadmill incline, you can compensate for the difference in energy cost, which changes the tide towards outdoor runners, giving them a better running economy.
So, what makes treadmill running harder?
To prove this notion, various athletes tried running at the exact calibration on different treadmill models, both new and used. Even though the results were inconclusive, most reported a difference in pace for all the models.
Your running form is low on a treadmill because you lack the freedom to exert yourself on the belt as you would outside. Treadmill running requires you to adhere to user weight and height to resemble the run outdoors.
While this sounds petty, it's true in so many ways.
Treadmills lack natural inclines and declines as you would get when running downhill or having the wind on your back assist you to power through. But treadmills are consistent, and you can set a specific speed and maintain it for a specified period as you wish with zero interruptions by the terrain or weather.
Treadmill workouts target the same muscles all the time. Because of this difference, treadmill running isn't the best for competitive athletes looking to become efficient runners. Seeing that you don't use all your muscles on the treadmill, it makes sense that your speed will go down.
There's also a risk of running an injury on the treadmill because of overusing the same muscles when running every time. The more muscles you work, the better the running efficiency.
Heat affects runners in different ways and can slow you down when you can't take it anymore. You can't control the heat when running outside, but you can dress for the weather, making it easier to push through. Likewise, running in chilly weather makes you run faster.
Even though you can make your running experience lively by switching on the TV or listening to your favorite podcast or music as you run, treadmill running is physically and mentally tasking.
According to a 2016 study by IJERP, it's easier to stay focused on running outdoors than on a treadmill. Even though the study is about the difference between outdoor and indoor cycling, the dynamics remain the same for running.
The good news is you can make treadmill exercises better by incorporating different training programs. For example, you can join group training and interact with others to cope with mental boredom or try HIIT treadmill routines that work you hard, so you don't have the time to get bored.
Other runners change the boredom to their advantage by using it to build mental toughness. For example, running a marathon is easier to maintain a steady pace when running in a group. But you will need mental toughness to run at a steady pace when isolated from the pack.