Injury Breakdown: Exercises in Futility - Lower Body
By Abby Sims
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Parts two, three and four of the "Exercises in Futility" series will address lower body exercises more likely to result in injury than benefit. Safe alternatives utilizing better and less stressful mechanics are offered in order to reduce the potential for injury. Here are a few of the prime offenders targeting the lower body that will be discussed:
- Dead Lifts
- Full Arc Leg Extensions
- Deep Squats
- Full Arc Back Extensions
- Hurdlers Stretches
- Hamstring Stretches with the Leg Propped Up too High
1. Dead Lifts
There are a number of conflicting instructions as to how to correctly perform a dead lift. The problem is that no matter which way you slice it, unless you lift competitively and have no choice, there are safer ways to strengthen. In my opinion, why risk it?
The purpose of an exercise often referred to in the literature as a Roumanian Dead Lift is to strengthen the hamstrings and low back by moving from a forward bent position to an upright posture by extending the back and hips while straightening the knees from a minimally flexed (bent) position. This is the type of Dead Lift that I see most people doing in the gym. Dead Lifts put the low back at risk, particularly for those who round the back during the lifting and lowering of the bar. A rounded back places the low back in a compromised position in which spinal structures are stressed (ligaments and discs). As the exerciser rises to an upright position (against gravity and the added resistance of weights) this stress increases. If you hold your breath there is even greater risk due to increased intra-abdominal pressure.
One reason the Dead Lift receives so much attention is that it works the hamstring in a very different way than the traditional leg curl motion. In this exercise, the hamstring is utilized to extend the hip rather than to bend the knee. The exercise also incorporates a vigorous eccentric component for both the hamstring and low back extensors. An eccentric contraction is a lengthening contraction during which the muscle works while controlling the release from its shortened position – in this case while the trunk is lowered. Eccentrics are very beneficial in training, especially because muscles can be safely loaded with more resistance during their lengthening or eccentric phase than that for shortening (the concentric phase).
It should be noted that muscles that cross two joints are at a mechanical disadvantage in working at one joint when contracted over the other joint. For instance, the hamstrings (in the back of the thigh) cross both the hip and knee. If the knee is maintained in an almost straight position, as for the Roumanian Dead Lift, the hamstring will act to extend the hip. In contrast, if the knee is held in a bent position (with the hamstring contracted), the gluteus maximus muscle (in the buttock) will be the primary muscle recruited to extend the hip. This is why variations on the dead lift, where the knees are bent while flexing the trunk forward, don't isolate the hamstrings. These variations are more similar to squats, which activate the gluteals, quadriceps, hamstrings and adductor (inner thigh) muscles in concert. This lift is sometimes referred to as the Bar Bell Dead Lift. This type of lift is a safer alternative though I am still not a big fan. Here the exerciser still lowers the bar placing stress on the lumbar spine (low back), though now with bent knees that (hopefully) remain behind the plane of the toes. The lift comes more from the lower body than the back in this exercise, encouraging more of a push through the heels rather than a pull from the lumbar spine.
There are a number of safe options for hamstring and back extensor strengthening that do not entail the risks inherent in the Dead Lift. The most obvious for the hams is the leg curl machine. Here it is preferable to work each leg individually to avoid having one's stronger leg exert more in order to compensate for the weaker side when both are worked together.
Another option is the standing leg curl – performed by standing on one leg with the thighs parallel, drawing one heel toward the buttock on that side and slowly lowering it to the starting position. Ankle cuff weights can be added to increase the level of difficulty. Also done with cuff weights, the traditional hamstring straight leg raise is executed by lying prone (on your stomach) with pillows under your hips to support you in a forward bent posture. Contract your abdominals and raise one lower extremity (with the knee straight) toward the ceiling without allowing your back to arch. Repeat for two to three sets on one side before beginning on the other. This straight leg raise can also be performed over a physioball or in a quadriped position (on hands and knees), both of which enable you to work through an increased arc of motion.
For the person just beginning an exercise program, initiating rehab for a hamstring, or whom experiences pain with other hamstring exercises, the most basic hamstring exercise is an isometric hamstring curl. Isometric exercises involve the exertion of force (a change in tension of a muscle) without a change in its length (therefore without movement). Lying on your back with your knee bent to a right angle (90 degrees) and your heel resting on a large physioball, push your heel into the ball for a 10 count; Repeat for two to three sets as for other strengthening exercises. You can also perform another version of hamstring isometrics by lying with your knees bent and feet flat on the exercise mat. Push one heel into the exercise mat and hold for a count of 10. For all strengthening exercises, repeat all reps on one side before continuing switching to the other.
Some Dead Lift alternatives for the low back extensors include:
- Locking your ankles down on a prone leg curl machine, tightening the gluts and low back while raising the head and trunk up from a flexed forward position to a neutral posture.
- Performing a version of the above while lying on an exercise mat. Begin with pillows under the hips to start from a flexed position.
- Extend the trunk from a flexed to a neutral position while supported on an exercise ball. .
- Lie on your stomach over pillows (at the hips) and alternate raising one arm and then the other. Keep the abdominals tight.
- Perform the above exercise alternating straight leg lifts instead of arm lifts.
- In the prone over pillows position, raise one arm and the opposite straight leg simultaneously. Repeat with the other arm and leg. Alternate. This is called a Pointer Exercise. Keep the abs tight.
- The Pointer can also be done over an exercise ball or in a quadriped position (on hands and knees) to increase the degree of difficulty.
Subsequent posts will review the remaining lower body "Exercises in Futility".
Related articles
- Injury Breakdown: Exercises in Futility (newyork.cbslocal.com)
