If you’re looking for some challenging exercises, look no further than your own body. Weight training is great for adding muscle, because you are able to push yourself and begin lifting weights that exceed your body weight. The ability to lift your own bodyweight, however, is a sneaky gauge of true strength. There’s a reason the military and certain athletes, especially gymnasts, train with primarily bodyweight exercises. It’s a safe and effective way to really get shredded. Think about how strong a soldier is. You may not even know because of the uniform and all the gear, but America’s freedom fighters are some seriously in shape individuals. Gymnasts aren’t as covered up, and it’s easier to take notice of their physique. Take a page from their hypothetical training book and begin using some challenging bodyweight exercises to get pumped up and take your body to the next level.

You are probably familiar with traditional bodyweight exercises like the pushup, pull-up, dip or sit-up. These exercises are challenging in their own right, especially pull-ups, but the evolution of the fitness monster has given birth to a new range of more challenging exercises that require nothing more than you, your body and just enough space to workout and move freely. Here are few challenging bodyweight exercises to add to your workouts and give your body a new test of true strength.

Pull-Ups & Dips: Wondering why this is first on the list? They may be a traditional exercise, but it is the definition of a bodyweight exercise, because you are doing exactly that: lifting your body weight through the strength of your arms, shoulders and upper back. These exercises will always be challenging, and chances are, they are not part of your workout. If you aren’t at the point where you can perform a full pull-up or dip, start with assisted pull-ups and dips and keep working. If 5 is your max, keep pushing until you can do 10. Always have a goal in mind.

Burpees: Probably the oddest-named exercise out there, but this exercise has always been a staple of the military. Begin by standing up, then squat down with a slight bend at the waist enough for your hands to plant on the floor. Next, kick your legs out behind you, keeping your arms straight. At this point you should look like you’re in the “up” position of a pushup. From here, tighten the core, bend the knees and hike your legs back underneath your body and stand up. For an extra plyometric experience, instead of simply standing back up, actually jump up and extend your arms up in the air before performing another rep. The entire exercise should be one fluid motion. Perform 10-15 reps and do 2-3 sets.

Push-Up Y Kicks: Pushups are another traditional exercise, but with a little twist, you can make them more challenging. They have tremendous benefit for upper body strength and should be a part of your workouts. Start in the up position, and as you lower your chest to the floor, kick your legs out into a “Y” shape, just a little wider than your shoulders. As you pushup, kick your legs back together. Perform 15-20 reps and do 2-3 sets.

Low-Plank Obliques: The plank is a great exercise for building core and abdominal strength, but adding some oblique work to it makes it more challenging and helps you work all areas of the abs. Assume the low plank position up on your toes and elbows and maintain a straight line form your head to legs, so that your butt isn’t pointing too high in the air. From here, lift your right leg up toward your right shoulder. Return it and then switch legs. Perform 20-30 reps and do 2-3 sets.

These challenging body weight exercises will be a great addition to your workout routines. With these four alone, your upper and lower body, as well as your core, will be pushed to the limit.