Shaping Your Rear Thighs with Lying Leg Curls
Written by Shoshana Pritzker Monday, 17 May 2010 18:28
By Stephen E. Alway, Ph.D.
The rear thighs are often tough areas to shape for many women. This area stores body fat rather easily and it’s usually close to the last area to give up its fat reserves, even when you are in strict dieting mode. Having weak and soft rear thighs accentuates this problem. The rear thigh is not a major problem for athletes who run, jump or ski because they must constantly work hard on this area to have strong and flexible posterior (rear) thigh muscles or hamstrings if they wish to be at the top of their game. In contrast, if the posterior thigh muscles are underdeveloped, the back of the thigh can take on a soft and saggy appearance and even simple things like climbing stairs, or stepping up a foot stool to reach something on a top shelf will be harder than it needs to be.
Even slim people can possess soft, untoned and weak hamstrings that detract from the overall shape of the thigh, especially from a back view. Nevertheless, don’t think for a moment that you have to be a competitive athlete in order to develop a firm and shapely rear thigh. It does not matter if you were born with unshaped and soft posterior thighs, or if your muscle tone in this area was lost over a number of years; it’s never too late, nor is it an impossible task, to become the proud owner of a better rear thigh. Targeted training for the posterior thigh area can help to firm, form and lift the entire area, and coupled with some cardiovascular work and proper diet, you will never have to worry about looking less appealing from behind than you’d like.
Structure and Function
The hamstring muscles consist of the long head of the biceps femoris and the semimembranosus and semitendinosus muscles. The hamstring part of the adductor magnus is also an important accessory muscle.
The biceps femoris muscle is a two (“bi”) headed muscle that lives on the posterior thigh (“femoris”; the femur is the thigh bone). The long head of the biceps femoris attaches to the ischial tuberosity. The ischial tuberosities are the bony parts that you sit on when you are in a chair. The fibers of the short head of the biceps femoris begin on the lower one-third of the femur bone, just above the knee. Because they do not attach to the ischial tuberosity, the short head is not considered a “hamstring” muscle. Both heads of the biceps femoris muscle fuse into a thick tendon, which crosses the lateral side of the knee joint to attach to the fibula bone (and some ligaments) near the knee.
The semitendinosus muscle is part (“semi”) tendon (“tendinous”) and part muscle. The semitendinosus fibers attach to the ischial tuberosity and insert into a cord-like tendon about two-thirds of the way down the posterior thigh. The semitendinosus crosses the knee joint posteriorly to attach to the medial side of the superior part of the tibia bone (the large medial bone of the lower leg). The semimembranosus muscle is partly ("semi") membrane (“membranous”) and partly muscle. It begins on the ischial tuberosity of the hip and it attaches to the posterior part of the medial condyle of the tibia just below the knee joint. The adductor magnus muscle primarily acts as a thigh adductor and it pulls the thigh close to the mid-line of the body. However, a vertical portion of the adductor magnus is called the “hamstring part” because it attaches on the ischial tuberosities and runs to the adductor tubercle on the femur. The adductor tubercle is a small prominence of bone just above the knee joint on the medial side of the femur bone.
“True” hamstring muscles cross both the knee and the hip joints posteriorly and they can both extend the thigh at the hip joint (i.e., they help draw the thigh posteriorly, as when running) and flex the leg at the knee joint (bring the heel toward the buttock). The short head of the biceps femoris only flexes the knee and the hamstring part of the adductor magnus only extends the thigh at the hip joint.
Lying Leg Curls
It is difficult to activate both functions of the hamstrings in a single exercise. To get around this problem in the leg curls, one end of the muscle group is fixed (at the hip joint) by lying on a bench and the knee is allowed to move.
1. If possible, choose a bench that’s not perfectly flat, but one that has a slightly raised part for your hips. The hips will be in a slightly flexed position (about 120 degrees is ideal) when you’re on the bench. Flexing the hip slightly allows you to use more resistance because your hamstrings are stretched and more mechanically efficient to lift the weight. A perfectly flat bench generates rather large torques through the lower back, which increases the risk for back injury, but this is greatly diminished on the benches that permit hip flexion.
2. Lie on your stomach and if your machine has handles, grip them to provide additional support and stability to your upper body. The top of your knees should be just beyond the edge of the main bench pad upon which you are lying. Adjust the length of the leg bar so the ankle pad, or roller, sits just above your heel over your Achilles tendon.
3. Start pulling your heels toward your buttocks. Keep your hips on the bench and do not let them lift upward during the exercise.
4. After moving your heels a few inches, plantarflex your feet by pointing your toes away from your head (as if you were standing on your toes). Plantar flexion decreases the effectiveness of the gastrocnemius (calf) muscles to contribute to knee flexion. It will make the exercise much harder when your gastrocnemius muscles are functionally removed in this manner. However, it will really start to shape your posterior thigh.
5. Continue to flex your knees with the intent of touching your buttocks with your heels. This should be done under full control and not with a ballistic momentum-stealing repetition. You might not quite make it that far, but pull as far as you can. Hold the top position for a two- to three-second count.
6. Slowly lower your legs to the starting position, but do not straighten your knee completely or let the weight stack touch down. Immediately after reaching the end of the repetition begin the next repetition. Aim for 12-15 repetitions before resting.
Important Tips
Spend your time between sets stretching your hamstrings. Lock your knee(s) out straight and slowly pull your chest toward your thigh by flexing your trunk, but try to avoid straining your neck to do this. Hold each stretched position for at least 10 seconds and repeat this at least twice before moving to the other leg. Stretching the hamstrings is a very important preventative measure that should minimize the chances of obtaining back injuries or pain that results from having hamstrings that are too tight.
Your posterior thigh and hamstring strength should be about 60 percent of your quadriceps strength, and anything less than this places the hamstrings at risk for injury. Not only will working your hamstrings allow you to regain the proper strength ratios around your knee joint, but it also just might be the stimulus you need to develop that firmness, sweep and shape that will be a total knockout blow once you arrive at the beach next summer. The leg curls as described here with ankle plantarflexion are harder to do than leg curls performed without plantar flexion. This means you will have to concentrate and focus more on this exercise. Concentration is actually an important key to your posterior thigh success. To effectively work the posterior thigh, it takes more than just going up and down with your heels. You must engage your mind and focus on performing the exercise strictly and correctly. It is too easy to lift your hips, or move your ankles from plantar flexion into dorsiflexion (bending backward) and this will bring other muscles into play, so it’s important that you do the exercise strictly and under full control.
Now, I know hamstrings may not be as exciting to train as other body parts, but never use this as an excuse to avoid hamstring work. Improvements in hamstring tone can take a flat and lifeless or overbulked and soft rear thigh, and turn it into a sleek and firm posterior thigh with a nicely arched shape. A stronger and firmer set of hamstrings will also give you a new spring in your step. If you have the determination and dedication to do it right, then adding a few sets of lying leg curls may be just the ticket you need to launch to the next level of beautifully shaped rear thighs. After all, don’t your training efforts deserve attention whether you are coming or going?
References
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