Most people know that exercises like mountain climbers can help you build muscle. But what specific muscles do mountain climbers work?
You can describe mountain climbers as doing high knees in a plank position which means mountain climbers are a type of bodyweight exercise.
Mountain climbers mostly engage your hip flexors, core muscles, glutes (butt), quadriceps (front thighs), and hamstrings (back thighs). They also engage a variety of secondary muscles to some extent. That being said, if you are serious about training these muscles you want to turn to strength training exercises instead.
If you are a resistance training beginner you may see some muscle gain in these muscles but soon mountain climbers will become a more cardiovascular-focused exercise.
Cardio vs resistance training
For someone who exercises every once in a while doing mountain climbers is mainly a cardiovascular-focused workout. Your cardiovascular system is the circulatory system inside of your body and includes the heart and blood vessels. These transport many types of important nutrients, oxygen, and waste throughout your body.
When you move more intensely by doing mountain climbers your body needs to transport these things, which means using your heart, at a higher rate.
Your heart is a muscle that can be trained by using it more intensely. By doing mountain climbers you can strengthen your cardiovascular system which in turn leads to a wide variety of other benefits (1, 2, 3, 4, 5).
It is true that mountain climbers will require certain muscles to work harder. One of the benefits of mountain climbers is that individuals who never do any resistance training will likely initially gain some muscle from doing this exercise.
However, even if you are able to gain some muscle with mountain climbers, this progress will usually not go on for long. If you are serious about gaining muscle you likely want to turn to resistance training exercises.
You don’t even necessarily need to use any dumbbells or barbells. Something like resistance band exercises can be a great start.
So in short, for a moderately active person the main body parts mountain climbers work out are your heart and lungs. Besides that, they also work out a variety of muscles. Do keep in mind that muscles can get injured. If you have not done any physical activity in a long time you may want to start out with low-intensity movements and build up from there.
Main muscles worked with mountain climbers
One of the benefits of an exercise like mountain climbers is that it engages both lower and upper body. Like with many exercises, this makes a variety of different muscles work. Even so, there are a few muscles that will have to work the hardest.
For most people, the core muscles, hip flexors, glutes, quadriceps, or hamstrings will be the first to fatigue when doing mountain climbers with the right technique.
Secondary muscles worked with mountain climbers
There are also other muscles that have to work during mountain climbers to keep your body in position. For example, your triceps (back/outer upper arm muscles) keep your arms stretched, your upper back muscles keep your upper back straight, and erector spinae keep the rest of your back straight.
Mountain climber variations for different muscles
You can also do mountain climbers on a slightly different surface or in a slightly different way to make the exercise focus more on certain muscles.
First of all, you can do mountain climbers with your arms resting on a stability ball to target your core muscles like abs and obliques (core muscles to the outsides of your abs) more.
A second variation is moving with your knee to the chest of the opposite side instead of going straight forward. This version that is also called twisting or crossbody mountain climbers will target your oblique muscles more.
How to make mountain climbers harder
Sooner or later most people have to do other exercises or make mountain climbers harder to keep seeing muscle gain results. Making mountain climbers harder at the right points in your training journey can also speed up muscle growth.
The first “way” is simply doing mountain climbers faster. The rougher, more explosive, movements will engage mainly your leg muscles more. Do make sure your technique is good before trying this out and pay extra attention to technique when speeding up.
Next, you can wear a weighted vest to make mountain climbers more challenging for your core muscles. The closer to your hips the more challenging for these muscles. If the vest only rests on your upper back it will only make the exercise more challenging for triceps and back.
Lastly, to make mountain climbers more challenging for your leg muscles and cardiovascular system, you can wear ankle weights, attach resistance bands to your legs, or put your feet on fitness sliders and move them over the ground.
Especially if you implement these more challenging variations of mountain climbers, make sure you give your body enough nutrients, rest, and sleep to repair and grow your muscles.