Mountain climbers are an 'underrated' exercise to improve core strength and cardio fitness together - here's how to do it

When it comes to high-intensity moves, it's fair to say I have a love-hate relationship with them. I love the sweaty, endorphin-fuelled high that follows them, but actually doing the exercise? Not so much.

I know that alongside beloved barre and home Pilates workouts, my body (and brain) need a decent sweat session. If the NHS guidelines that recommend 75 minutes of vigorous exercise every week weren't enough of a reason to do it, I came across a study in the Menopause Journal that found high-intensity exercise is especially effective in midlife for boosting quality of life and longevity. That's what we want after all.

It set me on a quest to find a high-intensity move that I liked. Enter the mountain climbers exercise. While it’s absolutely not my first rodeo with this move, it’s certainly not something I either look forward to doing or perform regularly in my bodyweight workouts, so I was interested to give this multi-purpose exercise a go.

What is the mountain climbers exercise?

Don’t worry: no actual mountains are required! Mountain climbers are a bodyweight strength and cardio exercise, performed in a plank position on the floor, as personal trainer Abbie Watkins reveals.

“Mountain climbers are a full-body, high-intensity exercise that mimics a climbing motion, but on the floor,” she tells us. “You start in a plank position and drive your knees towards your chest in a running action. It’s a simple move, but it delivers a big payoff for both strength and cardio fitness.”

Quite the full-body move, then, but they are also relatively simple to do. If you’re a beginner (like I am), you can perform them as slowly as necessary until you’ve gained more strength and cardio capabilities.

How to do the mountain climbers exercise

I asked Rowan Clift, training and nutrition specialist at AI-based fitness and lifestyle coaching app Freeletics, for his top technique tips on doing the mountain climbers exercise.

• Start in a high plank position with your hands placed directly under your shoulders and arms straight.
• Your head, shoulders, hips and knees should form one long line, with your core engaged to prevent the hips from sagging or lifting.
• From here, drive one knee forward toward chest level, then return it to the starting position as you simultaneously bring the opposite knee forward.
• Keep alternating legs in a smooth motion.
• One repetition is counted each time a foot reaches hip level, and one side counts as one rep.

Expert tip: "The key to good form is maintaining alignment through your core and keeping the shoulders over the wrists throughout the movement," he says.

Benefits of mountain climbers

1. They improve core strength and stability

While they may not appear to be one of the best core exercises on the face of it, there’s no doubt that mountain climbers really work the ab muscles.

“Mountain Climbers are particularly effective for the core,” notes Clift. “They work into the entire core area (the rectus abdominis, obliques and deep transverse abdominis) as they work to resist rotation and maintain stability.”

2. They're an excellent cardio exercise

However fit you are, there’s no denying that a set of mountain climbers will raise your heart rate fast. If you're looking for an alternative to your classic treadmill workout or dumbbell core workout, they could be a good option.

“Mountain climbers elevate the heart rate almost instantly, making them excellent for improving aerobic fitness,” agrees Clift. “This also means they have cardio-metabolic benefits when performed as part of a circuit, improving cardiovascular health and helping to maintain a healthy body mass.”

3. The mountain climbers exercise is low-impact

They might be high-intensity, but another advantage of mountain climbers is that they’re low-impact (because they’re performed on the ground) and they’re great for beginners.

You won’t need any specialist equipment, knowledge or skill to get started. They can be performed as slowly (or as fast) as you need, making them perfect for starting out, but also you can use mountain climbers as a way to track your progress. If doing the exercise gets easier as time goes on, that's a sure sign you're getting fitter.

4. They target the whole body in one move

Perform mountain climbers slowly, and you’ll really notice some strength and stability challenges. Race through them, and your heart rate will soar. They’re the definition of a full-body exercise.

“Mountain climbers are a time-efficient way to work multiple fitness components at once,” agrees Watkins. “ They build core stability, improve cardiovascular endurance, and strengthen your upper and lower body all at the same time.”

What muscles do mountain climbers work?

Having spent a week doing mountain climbers every day, I can tell you it would be easier to list the muscles the move doesn’t work. The experts certainly weren’t exaggerating when they said this is a full-body exercise.

“When done correctly, mountain climbers do not isolate one muscle group but instead demand a coordinated effort from the entire body,” advises Clift.

Specifically, though, I felt the most work in my core, hip flexors and arms, the latter two being my self-confessed shakier areas. Interestingly, the first thing to fail me (every time, no less) were my wrists. A joint rather than a muscle, but nevertheless, those of us with weak wrists might struggle with this one.

You’ll notice gain (and/or pain!) in the following muscles when doing mountain climbers:

• Shoulders and chest - these are constantly engaged in maintaining the plank position throughout the move.
• Triceps - support the arms as you hold your position.
• Hip flexors - working to drive the knees forward.
• Quads - help to power the forward motion of the legs.
• Glutes - are engaged to keep the hips level and stable.
• Hamstrings - this also helps with stability.
• Core - works to stop your trunk rotating, and to keep you stable in the plank position. You may also notice your abs ‘crunching’, as they would in a sit-up, as your knee drives forward, offering similar benefits to a sit-up or dead bug.

Do you need any equipment to do mountain climbers?

No, you don't need any equipment to do mountain climbers. However, if your home gym sits above your living room or you don't want to bother downstairs neighbours, you can avoid jumping by doing mountain climbers with Pilates sliders or a thick yoga mat.

Simple Pilates sliders sit under your toes as you do mountain climbers, giving you the freedom to move your legs in a running motion without any impact on the floor.

For those who struggle with joint pain or any hip or knee discomfort, this could also help lessen the load even more.