When it comes to running, there are two kinds of people: those who prefer running outside, and those who love going to the gym to run on the treadmill. Each of these two groups of people will defend their option with countless arguments.

In the end, it is a matter of preference, but we would like to take a closer look at the level of safety of each option. This article is not aimed to create a rift between free runners and gym goers. It is meant as a helpful guide both for beginners who have not made a choice, and as an eye opener for more seasoned runners, so that they can avoid injury while doing their favourite running routine.

Therefore, let us examine the conditions for each type of running and try to determine which one is safer.

Free Running

Either on a closed track or in the great outdoors, free running is the number one option for keeping fit for millions of people. Its number one advantage is that it does not cost too much (except for the running apparel and shoes). It is also great because you do not get bored, with the ever-changing scenery around you.

But this advantage can turn into a risk as well. If you are easily distracted by things you see around you, you may miss a bump in the track and fall down, possibly spraining your ankle. This risk of injury is multiplied by the fact that a lot of people (even some professional athletes) choose to listen to music on MP3 players while they are running, thus becoming oblivious to any warning noises.

On the other hand, free running helps you exercise your muscles better and helps you gain a correct gait. Every movement you make when your foot makes contact with the soil is different, and exercises all muscle groups in your legs. However, if you are running on a hard surface with inadequate shoes, running outdoors can cause shin splints and hamstring injuries.

Main Take-Away: Free running is great if you are a professional runner, and are good at focusing on your training and not getting distracted. Also, you need to use professional running shoes and know which type is adequate for the terrain on which you will be running.

Treadmill Running

Treadmill running is a great option for cold, rainy days. Even if you are a staunch lover of free running, you have to resort to going to the gym during late autumn and winter.

Treadmills are safer overall for amateur runners. They are provided with padding, so the impact on your muscles and joints is softer compared to free running. If you are just beginning to exercise and are a bit overweight, it is a great idea to start with the treadmill.

However, the main disadvantage of the treadmill is that your legs are not fully exercised. You are basically repeating the same type of step, and are not compelled in any way to correct your gait and vary the groups of muscles you are exercising. This repetitive exercise of the same groups of muscles leads to recurring cases of shin splints and IT band pain.

Observations by professional trainers have shown that treadmill runners tend to develop longer strides on the treadmill, trying to minimise the time when their feet are in actual contact with the treadmill. Several studies have also proven that running on the treadmill for a long time can change your posture, favouring the inward rolling of the ankle.

Also, if you happen to stumble on a treadmill, the consequences can be more serious than those of the same accident taking place on stationary ground.

Main Take-Away: The treadmill is a great complement to running outdoors, when inclement weather prevents the latter. However, continuous use of the treadmill may change your running posture, favouring the occurrence of accidents. It also favours repeated injury to the shins and IT band, which are the most exercised muscle groups during treadmill running.

The Verdict: Free running is healthier and better adapted to a complete work-out of your muscles. While the treadmill is great to keep fit during those days when you cannot do your running routine outside, you should not use it as a replacement for free running – both for fitness and health reasons.