If you have trouble getting your hamstrings to grow, you might be choosing the wrong exercises or failing to fuel your body properly. By adding a few basic exercises that target the hamstrings and eating enough protein to build up the muscle, you can save months — or even years — of frustration of not seeing results.

Your hamstrings are the muscles in the back of your thigh that go all the way from your hips down into your knees. You use them in almost any lower-body activity such as walking, running, biking, lunging and squatting.

Sometimes your hamstrings can get overshadowed by more visible muscles such as the quadriceps on the front of the thighs or the glutes. That doesn't mean they're not important, but they probably don't get the attention they don't deserve. Part of the reason might be that you can't see them in the mirror — out of sight, out of mind.

Hamstring-Specific Exercises

To get these long muscles to grow, you need to give them special attention and use exercises that isolate them. They work in tandem with the biggest muscle in your body, the glutes, during combination exercises like the barbell squat or deadlift. That means they get plenty of help and might not work as hard as they should.

Sliding Hamstring Curls

Lie on your back with your legs out straight. Put sliders under your feet or towels if you're on a hardwood surface. Pull your heels in toward your butt as you lift your hips into the air. Keep pulling in and pushing your hips up until your feet are flat on the ground and you're at the top of a glute bridge. Then, slowly slide back down to the starting position.

Romanian Deadlift

Start standing, holding either a barbell or two dumbbells in front of your thighs. Slowly stick your butt back, keeping your back flat, and lower the bar down your thighs, past your knees and down to the middle of your shins. Your knees should not come forward at any point, and all of your weight should be in your heels. From there, pull the weight back up and stand up straight.

Back Hyperextension Machine

This piece of equipment is in most gyms. Put your feet in the bottom on the platforms and your thighs on the thigh pads. Adjust the height so that the top of the pad is below your hips. Lower your upper body down as far as you can and then pull it back up by digging in your heels and pulling back with your legs.

Stiff-Legged Deadlift

Start standing with a dumbbell in each hand. Reach one leg back and balance on the other leg as you tip your upper body forward. Go down until the dumbbells are below knee-height and then come back up to standing.

Diet

Once you have your favorite hamstring exercises worked into your program, it's time to give your diet a quick check. Specifically, you need to know if you're eating enough calories and enough protein.

Calories

If your caloric intake is too low and you're losing weight, your body won't be very likely to divert energy and nutrients to building muscle. Adding new muscle is more of a luxury that you body can afford when you're eating enough.

Try monitoring your weight for a month and track your calories. At the end of each week, note how many calories you ate and how much weight you gained or lost. Then, up your caloric intake if you lost weight or keep it the same and even slightly lower it if you're gaining weight.

Protein

You should be eating 0.35 grams of protein per pound of bodyweight, according to the American College of Sports Medicine. Once again, track what you're eating for a week and pay specific attention to the amount of protein you consume. As an example, a 150-pound person should be eating at least 52.5 grams of protein per day, regardless of the source.