Can the treadmill replace outdoor running? This is a debate that continues to burn within the running community. As long as you train within your training pace, you will still reap the same benefits. However, the indoor enviroment is significantly different to the outdoors.

Firstly, you will not encounter the same degree of resistance or winds, be them tail winds or head winds. Due to the moving nature of the belt, you will use around 7% less energy, which is a negative effect if you are looking to lose weight. To overcome this, you can set the treadmill's incline to 1%. You may also run faster on a treadmill than on a road, which may be bad preperation for pacing and racing. It is also the case that many runners lean too far forward on a treadmill, which encourages bad form, again, not good for racing or injury prevention.

However, treadmills do have their place. If you run for fun, and not competitively, running 100% on the treadmill will still keep you fit and your heart healthy. If you plan to race however, you should get out on the road at least a few times a week. It is advised that you only use your treadmill for emergencies, such as when there is snow or ice on the ground, or when you would otherwise not be able to run. If it is too hot or too dark to train outside the treadmill is safer option - you can keep water near by and a fan on your face. If you plan to race in the summer, you should run in the heat to acclimatise, your body can adapt to the heat. (This process usually takes around 14 days).

Using a treadmill you can run at your exact pace, with or without hills. (Although, it must be said that the pace on some treadmills I have seen are very inaccurate). If you are a beginner that runs for fitness or fun, all of your running can be done on the treadmill guilt free. I encourage competitive beginners however, to do the majority of their runs on the road. And after all, the road is free.