If you’ve tried every butt-blasting, glute-sculpting workout you can find and still see flat or saggy results, you may just need to tweak what you’re doing to turn disappointment into an uplifting success.

VIDEOS: Top Trainers Share Their Favorite Butt-Toning Moves

Most butt-blaster workouts rightly incorporate squats, lunges, step ups and dead lifts. I’m not going to rehash or describe them here. You can find them easily online. I’m also not going to go into proper technique or discuss the risks associated with each exercise. You can find that elsewhere, too. What I am going to do is tell you how to adjust these exercises to actually make them work for you.

Up the Resistance

If you can do more than 12 repetitions of your chosen glute exercise, whether that’s squats, lunges, step ups or dead lifts, add more resistance. Ten barbell squats to fatigue will do more to shape your rear than 50 squats without added weight. To build muscle effectively, you must have enough resistance to make the exercise tough… so tough that you can’t do more than 8 to 12 repetitions. Add a barbell, dumbbells, sandbags, a weighted vest, a kettlebell—whatever you want. You can also increase resistance by switching to single leg squats.

Apply Plyometrics and Speed

Add a jump or hop to your traditional glute exercises. Do jump squats, step ups with a hop at the top of the motion (also holding a dumbbell for added intensity, if needed) and lunges with a jump between reps. Use caution when adding extra weight to these plyometric exercises. The extra weight increases injury risk but can also provide more dramatic results. On the cardio interval side, perform short sprints and side-to-side skater leaps to build and shape your glutes—if uphill, all the better.

Bring Your Thigh Closer to Your Chest

The more flexion you have at the front of the hip, the more work your glutes have to do to extend the hip. In practice, this involves leaning the torso forward slightly from the hip (not by curving the back) during exercises such as the lunge and step ups. The closer you get the thigh to the chest, the better. Also, with step ups, place the working leg at least 2″ higher than the trailing leg. This may mean skipping one or even two steps when using stairs or using a higher stool than you’re used to. The higher, the better, as long as you can perform the step up safely. Try to minimize push-off with the trailing leg.

MORE: Booty-Shaping Workouts for Your Butt Type

Pay Attention During the Lowering Phase

Normally we focus on the “up” or lifting portion of a squat, lunge, step up or dead lift. The “down” portion, or lowering phase, is at least, if not more, important. Take your time with the lowering phase, and control the motion to its end.

Avoid the Treadmill and Elliptical Machine

Treadmills and elliptical machines, because of the movement of the belt beneath you or the help given to the glutes of one leg by the hip flexors of the other leg, can lead to glute “shut down” or glute laziness. When possible, train on firm ground and preferably on hills and/or stairs. This does not mean you can never use these machines, but do not use them exclusively. When you do use the treadmill, incline it 5 to 7 percent.

Building and shaping your glutes requires intense work and places significant demands on your muscles and joints. Not all people can achieve the goal of sculpted glutes without injury. If you notice any signs of overuse or strain, decrease the intensity of your workouts and get with a trainer to make sure your exercise technique is correct. A great looking butt is nice, but a body functioning without pain is nicer.

Finally, realize that genetics do play a role in your results. The shape of your derrière is somewhat predetermined by the length of your tendons and where those tendons of your hamstrings and glutes attach to the bone. In addition, levels of various hormones such as testosterone, growth hormone and insulin-like growth factor 1 (IGF-1), affect how much muscle development you will achieve. Some people see more growth than they want, while others won’t quite reach the muscle development they wish for.

MORE: The Best Jean Pockets for Your Butt Shape