Treadmill runners usually fall into two camps. There's those that plug in an average speed and mindlessly jog for hours until they finally get tired, and there's those that know that cranking up their incline (a handy feature on most treadmills) can save time, burn fat and pack on leg muscle.


When it comes to getting the most out of indoor running, less is more, and experts agree that incorporating incline intervals into your run can help boost your fitness levels in a shorter amount of time.


The incline button tilts the treadmill belt upwards, creating imaginary hills for the runner and giving you the same challenge you might get while on an uphill jog.


"Running on an incline is an alternative way of adding intensity to a running working, without adding speed," says Melissa Weldon, head of training at boutique fitness concept Sweat It (sweat-it.com). "It makes your cardiovascular system work harder, while also working the glutes and hamstrings more than flat running."


As the incline increases, the muscles are forced to work harder, because the body must produce more power to propel itself against gravity. The effort needed to push yourself forward works many different parts of your lower body, from your gluteals to your hamstrings, and even the trunk muscles.


According to Ben Davie, a lead trainer at Digme Fitness, the nature of an incline will challenge your body in a new way compared to a flat run. "It's a great way to overload training which, in time, can improve your running efficiency and technique," he says.

"Incline running can be lower impact, if performed right," he adds. "It will also help to strengthen key areas for running, like the posterior chain. This can help you become a more efficient runner - running faster and for longer with less energy wasted."


Deciding how much of an incline to use depends on your level of conditioning and the results you're seeking. If you're new to the incline button, Davie says it's wise to start at slow speeds to avoid injuries like shin splints or plantar fasciitis (or heel pain). Begin by dialling up the intensity during a brisk walk so you can get comfortable with the extra effort needed.


"I'd recommend first-time runners alternate between power walks up a steep incline, for example 12-15%, and an incline jog (8/10/12kph) on an incline 6-8%," says Weldon. "This way, you can build your confidence on the treadmills without the higher impact of speed."


The only catch is that running on an incline is much harder than sticking to the flat, but that extra effort is the key to a more speedy workout. Researchers at the University of Georgia found that uphill running activates 9% more muscle with each stride, compared with exercising at the same intensity on level ground.


So although your workout might be a bit more gruelling, it means you can spend less time on the gym floor and more time enjoying that blissful post-run shower.