April 11, 2025, 7:20 pm | Read time: 5 minutes
Summer is gradually approaching, and with it, the desire for a well-toned upper body increases. So, what to do? Sure, sit-ups are a popular option. However, it’s also worth considering mountain climbers. Here’s a hint: This exercise, also known as “Bergsteiger” in German, is a true all-rounder. What should you keep in mind during training? Which muscles does the exercise activate? FITBOOK author Tony Poland spoke with a personal trainer about it.
To focus on a flat stomach, planks are perfectly suited. This full-body exercise using your own body weight, which is quite demanding, primarily targets our abdominal muscles along with the core or midsection. An even more intense version of this is the mountain climbers. Here, the climbing motion is simulated. But instead of climbing a steep wall, you move horizontally on the ground. This way, you can train both strength and endurance simultaneously, and you engage the entire body. It’s no wonder mountain climbers are among the most effective bodyweight exercises—if done correctly.
Overview
Starting Position and Procedure
You start in the plank position, but you can also begin in the push-up position. The body forms a straight line from head to toe, with the stomach and glutes engaged, and the gaze directed downward. Now, alternately pull the right and left knee in a controlled and bent motion toward the chest, while the other leg returns to the starting position.
Personal trainer Markus Bremen from Cologne tells FITBOOK: “To visualize it for people, I always say it’s like running in place. Or like high knees. Only, you do it in a supporting position.” Clearly, the faster you go, the more challenging it becomes, and the more endurance comes to the forefront.
Also interesting: Plank vs. Reverse Plank–two effective exercises for a strong stomach and back
Training Tips
It often happens that the back sags or the buttocks move up and down. This can be prevented by maintaining proper body tension, where the core remains stable and the back stays straight. It’s also important to maintain calm and even breathing, even at higher speeds. For more stability, it’s recommended to press the hands firmly into the ground or, better yet, into a padded surface.
Muscles Activated
Basically, mountain climbers are full-body exercises that train multiple muscles simultaneously. First and foremost, the focus is on the abdominal muscles or the core. The rectus abdominis provides stability and helps pull the knees in, while the obliques are active during lateral movement and core stabilization. The deep abdominal muscles are important for core control and body tension.
A second focus is on the leg muscles. The hip flexor, which is more part of the core area, helps pull the knee to the chest, while the back and front thighs stabilize the movement or work during stretching. Calf muscles assist with support. Our gluteal muscles are also engaged, as they support the stretching movement and keep the pelvis stable. Additionally, just by being in the starting position, shoulders, chest, and triceps are pushed, as well as our back muscles.1
Bremen: “There’s a division between primary muscles that are targeted and secondary muscles. Secondary would be everything that supports and keeps the upper body in a straight line. This includes arm muscles or triceps, shoulder muscles, and chest muscles. But the main focus is on the core.”
“An Exercise That Trains Endurance Extremely Well”
By the way: In addition to training many different muscle groups simultaneously, which builds strength, mountain climbers also promote coordination, balance, and endurance due to the movement sequence. The high intensity of mountain climbers also boosts metabolism, so we burn fat. It’s like hitting several birds with one stone. “It’s simply an exercise that primarily taxes the core and especially trains endurance extremely well,” emphasizes the fitness expert.
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Mountain Climber vs. Sit-ups
Of course, mountain climbers must withstand comparison with sit-ups, especially when it comes to muscle building, fat burning, and functional strength.
While our “Bergsteiger” exercise, as mentioned, focuses on the whole body, with an emphasis somewhat on the core or trunk, sit-ups mainly target the rectus abdominis. Mountain climbers also activate more abdominal muscles, especially the deep and lateral abs.
On top of that, unlike sit-ups, they can also serve as cardio training due to the dynamic movement, which melts significantly more calories. Stability, coordination, and core control are also much more promoted, which is crucial for functional strength in everyday life.
Conclusion: For visible abs, mountain climbers are much more effective than sit-ups. They are also significantly more versatile and functional, covering a lot more areas.
Mountain Climber vs. Crunches
Even compared to crunches, mountain climbers perform better overall in terms of the mentioned parameters (muscle building, fat burning, functional strength). Crunches, or “ab presses,” primarily target the rectus abdominis, have little endurance effect, and burn less fat. The functionality is also not as high.2
“Mountain Climber Significantly More Functional”
Crunches alone won’t fulfill the dream of a flat stomach or even a six-pack. Along with proper nutrition, mountain climbers are the far better choice due to their higher intensity and versatility–plus, they engage much more muscle.
“Mountain climbers are definitely preferable to crunches because they are significantly more functional,” says Bremen. “Pulling the leg in is something we do in everyday life, like running, walking, or climbing. With crunches, we don’t use the hip flexor at all. Instead, we move the upper body to the legs from the rectus abdominis. And that’s less functional in everyday life.” Additionally, crunches can more quickly provoke spinal problems if the exercise is performed incorrectly.