Unlike your boobs, your glutes are loaded with muscles that are capable of growing larger, so you can score the curvy butt of your dreams. Obviously, if you want those muscles to grow, you need to work them, says Tony Gentilcore, a certified personal trainer and strength and conditioning specialist, and co-founder of Cressey Performance in Hudson, Massachusetts. To score a bigger booty, he says to start by doing glutes-focused exercises, like the glute bridge and squats, while progressively adding more weight. (Gentilcore says you can do this by holding a barbell or dumbbells on your hips for the glute bridge and by holding a dumbbell in each hand for the squats.)
When you don't spend enough time strengthening your butt, your other muscles can pay the price, says Metzl. See, when your butt isn't strong enough to support you during activities the way it should, you put more loading force on your hamstrings, which can injure them or other muscles, joints, and ligaments that your hamstrings come in contact with—like your calves or knees. Metzl says that when a patient comes in to see him about an injury, weak glutes are often part of the problem. 
The hip flexors are a group of muscles in the front of the hip that act to lift the knee and bring the thigh towards the abdomen. The major muscles making up the hip flexors that we will focus on are the iliacus and the psoas, or the iliopsoas and the rectus femoris. The rectus femoris  is a “two joint muscle” because it crosses both the hip and knee joints. As a group, the hip flexors have attachments on the lumbar spine, the pelvis, and the femur. In addition to their major function of flexing the hip, their attachment on the spine makes them an important part of the core muscles and spinal stabilizers.
If your fitness goals are to get strong and build hard, visible muscle, then you’re going to want to train in three phases according to Heath. Strength, conditioning, and a blend of the two that works for you. “If you can get to the gym 4-5 days a week, that would be perfect,” he says. “You can still do chest/tri’s, back/bi’s, legs, shoulders, and make the fifth day a cleanup day, meaning focus on body parts you may be weaker in.” Check out Heath’s guide to finding your best muscle-building routine.
Firstly, let’s establish where your glutes are and what they actually refer to! Your ‘glutes’ — or your gluteal muscles, as they are more formally known — refer to the muscles in your butt. Specifically, there are three major muscles in this area: your gluteus maximus (the main, large muscle that shapes your backside), your gluteus medius and your gluteus minimus (two smaller muscles that assist the gluteus maximus in moving your body).
×