Running outside or on a treadmill: which is better for you? It’s a contentious debate.
Surely running is running, and it just comes down to personal preference, right?
Actually, running outdoors versus on a treadmill is quite different in a number of obvious and also subtle ways. It places the individual on a very different surface and in very different conditions. And these changes can have a significant impact on the outcomes of the activity, both in the short term and the long run.
There are many arguments about which produces greater physiological benefits, and recent research has explored the differences.
But of course, there are a range of other measures and experiences of the two activities that can impact the benefits for the runner that might supersede the physiological pros and cons.
But first, the recent research.
The Research
A study published last year in Peer J Life and Environment sought to compare a controlled running program, with one group executing the regime outdoors, and the other doing so on a treadmill.
Participants were randomly assigned to either treadmill training (TT) or outdoor training (OT). They participated in a six-week supervised training protocol. Physical fitness and body composition metrics were measured throughout the six-week trial.
The results indicated that both groups saw improvements in a range of fitness markers, and both groups saw decreases in body fat.
However, the outdoor group saw greater physical fitness improvements overall, and greater leg skeletal muscle mass preservation than the treadmill group.
The authors hypothesised that outdoor running places additional physiological impediments on the athlete than the treadmill does. That is, less stability underfoot, which means the athlete is working a little bit harder per step; less control over hills and terrain, which means you can’t decrease the difficulty of the trail, and so on.
But before we name the outdoors as the optimal environment for running, there are some other things to consider, that might just see you turning to the treadmill instead.
Why running conditions are about more than just short-term adaptations
Still on the research, it should be noted that the mean age of the participants in the study was 19.82, meaning they were young. This would give them physiological advantages for tackling the unpredictable nature and the demands of the outdoors. That is, hard pavements, inconsistent terrain, and varying weather conditions.
They were also starting from a solid health base. For those starting their program from scratch — perhaps you’re a little older, inexperienced or overweight — these conditions might not be conducive to you maintaining this protocol outdoors long term.
Additionally, the study indicated that outdoor running might produce greater results in the short term. The study was performed over six weeks. However, some of the elements of this activity might make it more challenging to continue consistently or long term.
Outdoors vs Treadmill — The Pros and Cons
The only thing between the outdoor runner and rock-hard pavements, potholes, and unpredictable undulations in the terrain, are their shoes. Stress related injuries are very common in runners and difficult to fully recover from. This can be particularly problematic for heavier runners and those just starting out, with the goal of losing weight.
On the treadmill, the softer and consistent landing places less strain on the body. Reducing the impact on joints, lowers the risk of injury or stress-related issues. This is especially true for individuals with joint problems or who are prone to overuse injuries. This keeps you running longer and more frequently.
Although the terrain and varying inclines of the outdoors keep the body guessing and keep things interesting and more demanding, the treadmill runner has more control over incline and resistance and can therefore tailor and measure their progress more effectively.
They can gradually increase the difficulty of the run over time, and in varying ways, without having to seek out tougher trails. They can also incorporate interval training, hill workouts, or target specific pace goals. It’s all there built into the treadmill.
Although wearable technology has come a long way, treadmills equipped with built-in technology and features that allow you to monitor and track your workout metrics, do so with with extreme precision. These data points can provide valuable insights and help govern the workouts you set for yourself within the treadmill.
The outdoor runner will argue that being in nature and battling the elements can be more invigorating and mentally engaging, which makes you more motivated to do it.
The flipside of that is (technology, console, and entertainment options aside), the treadmill puts you in a controlled and safer environment. You don’t have to worry about inclement and extreme weather conditions, such as heatwaves, heavy rain, or icy conditions, where outdoor running may be unsafe. Therefore, you are enabling consistency.
Running on a treadmill and running outside each have their own unique advantages and considerations. And the reality is, both are available to you. Incorporating outdoor and treadmills into your running program is the only way to gain the maximal benefit of both.
Singh, G., Kushwah, G., Singh, T., Ramírez-Campillo, R., Thapa, R.K. Effects of six weeks outdoor versus treadmill running on physical fitness and body composition in recreationally active young males: a pilot study. PeerJ. 2022 Jul 27;10:e13791. doi: 10.7717/peerj.13791. PMID: 35915754; PMCID: PMC9338755.
