Incline walking is having a moment, thanks to the 12-3-30 workout that took over TikTok earlier this year. That workout includes walking on an incline of 12% at 5km per hour for 30 minutes. Whether or not you do the 12-3-30 workout or you’re just curious about the fitness you’ll gain from cranking up the incline on your treadmill or finding the nearest hill to stroll up, there are plenty of reasons for runners to go slower on a steep grade.

To explain the benefits of incline walking versus running and what you’ll gain from adding hills to your routine, we asked experts to explain what you need to know about incline advantages. Plus, how to incorporate uphill walking workouts into your routine.

Incline Walking vs Running: The Similar Benefits You’ll Gain
Incline walking and running share many benefits, including:

Kicked Up Cardio
For starters, both incline walking and running are staple cardio exercises. Each activity gets your heart rate up and improves cardiorespiratory fitness, per the American Heart Association.

In general, running is more intense than walking, when you perform them on the same terrain. But once you start walking uphill, that incline adds resistance and your heart and lungs have to work harder to supply your muscles with blood and oxygen. “Running on relatively flat ground involves more horizontal movement, whereas walking uphill takes more vertical movement, and moving vertically against gravity is definitely going to be harder than moving horizontally,” says exercise physiologist Dean Somerset.

What’s more, the impact and push off of the ground you do when running creates an almost elastic propulsion from the muscles and tendons, which can be really beneficial for producing forward movement more efficiently, Somerset says. You don’t get that same benefit of forward momentum while walking a hill, so your heart works harder, offering a cardiovascular benefit comparable to running on flat ground.

Improved Muscular Strength
It takes a great deal of muscular strength to sustain your pace, whether you’re walking at an incline or running over flat terrain.

Both running and incline walking requires strong quadriceps (muscles in the front of the thigh), hamstrings (muscles in the back of the thigh), glutes (large buttock muscles), triceps surae (muscles of the calf, including the gastrocnemius and soleus), anterior tibialis (muscle of your shin) and abdominals, according to Somerset.

Compared to walking or running on level ground, taking your stride to an incline recruits even more of the quads, glutes, anterior tibialis, and calves. “Walking or running uphill changes the activation of the muscles you use because of the wider range of angles at which your hips, knees, and ankles are working,” says Dr. Todd Buckingham, a triathlete and professor of exercise science.

For example, the quads and glutes are more involved in walking uphill because the knee must come up higher in front of your body than walking on level ground and those glutes have to really power up to keep you moving upward. Meanwhile, the calves become more activated because your ankle is more dorsiflexed (that’s toes to shin) on an incline, Buckingham explains. It’s not uncommon to feel these muscles burning on your trek up a mountain or hillside.

And unlike walking or running on level ground, going uphill forces you to propel your body forward and upward, which requires more energy and force, Buckingham adds.

Boosted Kilojoule Burn
Incline walking and running also offer a comparable kilojoule burn, with running slightly higher.

Here are estimates for the number of kilojoules a 70kg person will burn from both activities for 30 minutes:

• Running at 10km per hour on level ground: 1400 kJ
• Walking at 5km per hour at a 1% to 5% grade: 750 kJ
• Walking at 5km per hour at a 6% to 15% grade 1100 kJ

Because both feet come off the ground when running, it’s considered a high-impact activity. In general, high-impact activities burn more kilojoules than low-impact options like walking or cycling. However, incline walking recruits the muscles in your legs to such an extent that the overall kilojoule burn is similar, according to Somerset.

The Differences Between Incline Walking vs Running
Where incline walking and running differ is in how much impact they place on the body. Again, running means hopping from one foot to the next, creating impact each time you land. That doesn’t happen when you’re walking, even on an incline, as you always have one foot on the ground. That’s not to say one is better than the other—it’s good to have some impact in your training routine, depending on what your body can handle on a given day. But high-impact activities often turn up the intensity, while adding more strain to your muscles, tendons, and joints.

With that impact in mind, it might explain why a study published in the Clinical Journal of Sports Medicine in 2000 comparing more than 5000 regular walkers and runners reveals that walkers had a significantly lower risk of activity-related injuries compared with runners.

What’s more: Research published in the European Journal of Applied Physiology found that uphill walking and running involve different biomechanical variables. While running, you actually change your centre of mass, foot-to-ground contact time, leg swing time, and stride—so it’s not just fast walking.

There are plenty of reasons for runners to go slower on a steep grade

A stand-out benefit of running, compared to walking, is that you can push your pace even more and work at a higher intensity than incline walking, which leads to greater fitness benefits. “For the most part, running will result in a higher heart rate than walking at an incline,” Buckingham says. “This helps strengthen the heart by increasing its elasticity, or how much your heart can stretch to fill up with more blood, and how much blood is pumped out with each beat.”

The higher intensity of running results in other changes that incline walking can’t offer. For example, running will help you develop more mitochondria—structures inside muscle cells that convert oxygen into adenosine triphosate (ATP), or energy, according to Buckingham. More mitochondria equals more potential energy for running.

“Running also increases capillary density in the muscle,” Buckingham says. Capillaries are blood vessels where gas exchange—the transfer of oxygen and carbon dioxide—from respiration takes place. Increasing capillary density allows the muscles to take in more oxygen for energy and eliminate more carbon dioxide, a waste product.

How Incline Walking Can Fit Into Your Training
“Incline walking can be used as a supplement or substitute for running, depending on your goals and what stage of your running life you’re in,” Somerset says.

How to Add Incline Walking to a Beginner Running Programme
“Beginners who struggle to run every day may benefit from alternating a running workout with an incline walking workout to build fitness,” Somerset says.

Beginners can also start with incline walking, and then gradually transition into jogging with 20- to 30-second intervals as their fitness improves and their muscles, joints, and ligaments get used to exercise, says Liza Howard, a certified running coach.

If you’re an absolute beginner—as in, you haven’t followed a walking or running programme for more than a year—Howard suggests starting with three incline walking workouts per week. Aim to walk for 30 minutes at 5km per hour and a 6% incline. If that’s too challenging, simply lower the incline and/or speed, Howard says.

How Seasoned Runners Can Add Incline Walking to their Routine
For more experienced runners, an incline walk can be a great way to mix up their training and give their joints a break from pounding the pavement, says Somerset. Try an incline walk in place of an easy run on your training plan.

In addition, Howard often recommends incorporating incline walking into race training, especially if the race course has elevation changes. “To maintain a constant effort throughout a race, it helps to switch to a fast walk when you’re going uphill,” she says.

Fast-walking uphill takes practice, though, Howard adds. So, try incorporating incline walking into a training run. On a treadmill, run for nine minutes, and then bump up the incline and walk fast for one minute, Howard suggests. How steep you put the incline and how quickly you walk will depend on your fitness level; aim for an incline and pace that feels challenging but doable. Because you’ll need a treadmill to do this, you may want to save this workout for a shorter training run (i.e. 30 minutes).

The Bottom Line on the Benefits of Incline Walking vs Running
Incline walking and running can both work your muscles, improve your fitness, and burn kilojoules to a similar extent—they’re simply different approaches.

“It’s like driving a car versus a motorcycle to the grocery store,” Somerset says. Either modality will get you to your destination, but the approach varies.

Furthermore, neither modality is better than the other. “The best option will be the one you feel gets you the workout you’re after, and that you enjoy,” Somerset says.

The option you choose also often comes down to your goals. That brings us to one last thing to keep in mind: If your goal is running a race or you’re looking to score a faster time on the run, practicing your specific sport is smart. In other words, running will win out when it comes to prepping your body for a run PB. But even in that case, you can still incorporate incline walking into a couple of your easy runs or hill interval workouts, which will help you master steep inclines.

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