While flexibility is one of the five health-related components of physical fitness (along with muscular strength and endurance, cardio respiratory endurance and body composition), some of our most common orthopedic injuries can be partially attributed to poor flexibility. Approximately 80% of the U.S. population will experience back pain sometime in their lifetimes. In the workplace, back injuries are the number one problem, and overuse syndromes are number two. Among athletes, common complaints include back pain, leg pain and various shoulder problems. In all of these situations, too much or too little flexibility can contribute to poor body mechanics, which increases the risk of injury.

Ignoring the flexibility component of fitness is like not maintaining your car but continuing to drive regularly. Over time, the chances of your car having problems will increase. It could be as simple as being unable to start your car or getting a flat tire. It could be as bad as having a serious accident because your brakes don't work. If you don't maintain your body by including all five health-related components in your fitness program, your likelihood of having health problems is greatly increased as you get older.

In reality, most people have some areas of hypomobility (decreased flexibility) and hypermobility (flexibility that is beyond normal). Lack of flexibility means your muscles may work harder to perform an activity, you may be substituting one movement for another or performing movement with poor body mechanics. For example, if you have tight hip flexors, when you walk your hip extensors have to work harder to propel your body forward. This is most obvious in the last phase of walking when you push off with the back leg. It is not uncommon for people with tight hip flexors to substitute hip extension with lumbar hyperextension while pushing off with the back leg. Additionally, tight hip flexors can also lead to increased internal rotation of the hip during activities that use the legs. The increased internal rotation can compromise the body mechanics of any of the joints in the lower body including the hips, knees, ankles and feet.

Conversely, it is also possible to be too flexible. Injuries are more likely to occur when you do not have the strength and endurance to protect your joints throughout their available range of motion (ROM). A joint that has more ROM than expected is called a hypermobile joint. There are many sports, such as gymnastics, swimming and pitching, in which increased flexibility can create some mechanical advantages. Flexibility coupled with strength in the upper body can help athletes excel in all of these sports. However, due to the nature of the activities, upper body overuse injuries can also be found. In the case of an overuse injury, there is often a lack of functional flexibility.

Flexibility looks at the ROM available in a joint. Functional flexibility means you can use this ROM correctly when you need it. In other words, it means having the correct combination of flexibility, strength, endurance and coordination to perform everyday activities with proper body mechanics. For example, if someone cannot reach overhead, and you only work on increasing their shoulder flexibility, then you haven't worked on all the components of functional flexibility. Everyday activities that usually require reaching overhead include combing your hair, hanging clothes in a closet and getting a cup out of an overhead cabinet. Most people have the flexibility to reach overhead with both arms. However, most of us do not have the functional flexibility to easily comb our hair, hang our clothes in the closet or get a cup out of an overhead cabinet with our non-dominant arm. This is because most people never practice these activities with their non-dominant arms.

The ideal flexibility program includes more than the static stretches typically found in most warm-ups and cool-downs, although they are still important to make sure a person has the necessary ROM available to do their activities. Some form of dynamic stretching generally helps address the combination of flexibility, strength, endurance and coordination. As an example, someone with tight hip flexors will benefit from doing static stretches that isolate the iliopsoas and rectus femoris. For functional flexibility, they could work on getting full hip extension while doing various aerobic activities like walking, running and taking step class.

Before starting clients on a functional flexibility program, assess their available ROM in a static position. Use static stretches to help any areas of inflexibility. Once clients have the ROM in a static position, you'll figure out how to incorporate the use of it through dynamic stretching activities.

Screening for Flexibility

Following are some basic screening tools for common areas of inflexibility. Test both sides of the body. Even with the spine, it is possible for the muscles on one side to be tighter than on the other side. Because we are testing functional flexibility rather than maximal flexibility, it is not necessary for the client to warm up before these screenings. The client should demonstrate their pain-free range. Any range that is uncomfortable or requires an extensive warm-up will probably not be used in normal circumstances and therefore isn't usually a functional ROM for everyday activities.

Pectoral muscles: Have your client lay supine on the floor with the knees bent, feet flat, and the arms relaxed at the sides. You should not be able to place your entire hand under their shoulder. If you can, then the client may have tight pectoral muscles. Before doing this assessment, make sure your client does not have increased thoracic kyphosis or this test is not valid.

Shoulder internal rotators: When standing or sitting with the arms relaxed and hanging by the sides of the body, the palms should face the body. When you look at the person from the side, you should be able to easily see all four fingers and the thumb. If you cannot see the thumb and index finger, then the shoulder internal rotators are too tight. In more severe cases, the palm will actually face backward.

Lumbar extensors: Ask your client to lie supine on the floor with the feet flat and the knees bent. The lower back should touch the floor in this position without the client having to consciously contract the abdominals. Kneel beside your client and see if you can fit your hand in between their lower back and the floor. Move to the other side and check again. If the lower back is not flat in this position, your client has decreased flexibility in the lumbar spine.

Hamstrings: Have your client lie supine on the floor with both legs straight. Kneel to the side of your client and help him or her lift one leg as far as is comfortable, with you holding the majority of the weight of the leg. Most people should be able to lift their legs to 90 degrees of hip flexion without any pain or discomfort. Inability to assume this position could be due to tight hamstrings or various back problems. If the client complains of muscle tightness in the back of the thigh, the problem is most likely lack of flexibility in the hamstring muscles. If the patient complains of back or hip pain or nerve pain (characterized by numbness, tingling, a sharp pain or something that feels like electricity), they should be referred to their physician. These symptoms could indicate possible spinal or sciatic nerve problems. Move to the other side of the client and repeat the test on the second leg.

Hip flexors: While lying supine on a weight bench, your client should start with both knees flexed and held to the chest and the lower back pressed to the bench. Your client should be able to hold one leg in and then take the other leg and extend the hip while keeping the knee bent 90 degrees. The low back remains in contact with the bench and the thigh stays in alignment with the rest of the body. Inability to assume this position indicates tightness in the iliopsoas and/or rectus femoris. Bring the first leg back to the starting position and then lower the second leg to test the other side.

Hip internal rotators: Have your client sit in a chair and put one ankle on top of the other thigh. Their lower leg should be parallel to the floor. If it is not, then they have tight hip internal rotators. Return to the starting position and test the other leg.

How to Perform Common Stretches Correctly

Stretching Into the 21st Century: Part One ("CEU Corner,"January/February '98) covered the differences between stretching during the warm-up for permanent increases in flexibility and how long to hold the stretches. Various techniques, including the CRAC method and static stretching, were discussed. This section focuses on body positions and tips for isolating various muscles and muscle fibers.

The sensation of stretching is occasionally described as uncomfortable or painful. In all the positions, the client should feel the stretch somewhere in the muscle or tendon area unless they are hypermobile in that joint. The sensation of the muscle stretching should decrease as the position is held. If the client wants to increase flexibility, he or she should move further into the stretch as the position becomes easier to hold. They should never experience any pain that causes them to contract the target muscle or surrounding muscles, or joint pain or nerve pain. Joint pain is characterized as the feeling of bone rubbing on bone and is located within the joint itself. Nerve pain is associated with tingling, numbness, sharp pain or a feeling like electricity is running through you.

For a hypermobile joint, the client should only go to the position that is considered normal ROM for them. If they do not have muscular control of their current ROM, then increasing their range only elevates the injury risk. Typical clients with hypermobility include children, female adolescents and prenatal women. Again, be aware that some people may be hypermobile in one joint, but hypomobile in another area.

The general rule for determining the best positions to statically stretch a muscle is to first decide how the muscle works concentrically. Then, move in the opposite direction and make sure the body part being stretched is supported against gravity so the muscle can relax in that position. As an example, when stretching the hip adductor muscles, most people use a seated straddle position to stretch one or both adductors. The adductor muscles pull the legs toward the midline of the body, so sitting in the straddle position moves the legs in the opposite direction. Because you are seated on the floor, it bears the weight of the legs so the adductors can relax. However, to increase the stretch, people often flex their trunk forward. Because the adductor muscles do not attach to the spine, this will not directly increase the stretch to the target muscles. To increase the stretch, the participants should assume a wider straddle position by moving their legs into more abduction, not by flexing the trunk forward. You should also be aware of how much ROM is necessary for your client's functional activities. A gymnast requires much more flexibility through the hip adductors than normal. To focus on increased flexibility in an area where you do not typically work on increased strength could predispose participants to future biomechanical problems.

Pectoral muscles: The most common chest stretch involves bringing your arms behind you and clasping your hands together. To maximize the effect of this stretch, adduct your shoulder blades, externally rotate the shoulders so your palms face away from each other and maintain a neutral spine.

Tip: The pectoralis major is a fan shaped muscle, and it will take more than one stretch to maintain flexibility in all of the fibers. The best flexibility programs will stretch all of the pectoralis major fibers. Bring the arms behind you with the arms below shoulder level, at shoulder level and then with the arms above the shoulders. By stretching with the arms in all three positions, you will stretch the upper, middle and lower fibers of the pectoralis major.

Low back stretch: The most common back stretches involve supporting the weight of the upper body by placing the arms on the floor (or the legs, if stretching in a standing position). Then, flex the spine. However, most clients flex through the thoracic spine, where they have more flexibility, rather than the lumbar spine. Encourage clients to round the low back rather than the upper back.

Tip: The erector spinae are actually several different muscle groups which extend the entire length of the spine. To stretch all of the muscle fibers, you have to flex all the parts of the spine. Generally, you'll be doing great if you can get your clients to understand the difference between rounding out the upper and lower back. By stretching both areas, you'll help them avoid getting stiff areas in their neck and back.

In standing and sitting, it's normal to have a small lordotic curve in the lower back. When you are stretching the lower back muscles, you should see a complete reversal of the curve at the waistline. If you'll have your clients stretch their lower back before they do any abdominal work, they might be surprised at how much easier it is to stabilize and/or flex the spine.

Hip flexor stretch: To stretch the hip flexors, the hip should be in extension with the thigh, directly in line with the trunk, or slightly behind it, while the spine maintains a neutral position. Participants often hyperextend their lower back to get their leg behind them but don't realize that they never fully extended their hip.

Tip: Because there are several different muscles that can perform hip flexion, many clients will benefit from rotating the hip in slightly different positions to vary the fibers that are stretched. Because it is difficult to balance on one leg while trying to stretch the other, a good base of support is needed before you vary the position of the leg being stretched. There should be little to no weight on the leg being stretched when you are rotating the hip to vary the positions.

Hamstring stretch: The hamstring muscle extends the hip and flexes the knee. To get the most out of your stretch, you have to flex at the hip and straighten the knee. In some cases, fitness professionals mistakenly instruct their clients to keep the knee bent to protect the joint. It is correct to stop your clients from hyperextending the knee. But you have to extend the knee to a straight position to effectively stretch the hamstrings with clients who have normal flexibility in this area.

You need to position the thigh in front of the body to effectively stretch the hamstring muscles. To save time, instructors and personal trainers may try to have their clients stretch their hamstrings from a seated straddle position. It is difficult to effectively stretch the biceps femoris (most lateral hamstring muscle) in this position.

Tip: Again, because there are three hamstring muscles, it is best to slightly rotate at the hip to vary the positions for stretching out the hamstring muscles. Because the biceps femoris is usually the least stretched hamstring muscle, clients will often feel the most difference when they slightly roll the hip and knee in for internal rotation. There should be little to no weight on the leg being stretched when you are rotating the hip to vary the positions.

Calf stretch: The gastrocnemius flexes the knee and plantar flexes the ankle. For the most effective stretch, extend the knee and dorsi and flex the ankle. It's the same situation as with the hamstring muscle. Do not allow the participants to hyperextend the knee, but make sure they extend it to a straight position.

Tip: When performing the standard standing calf stretch with one leg behind, make sure that your client performs the stretch correctly. On the back leg, the knee should face forward and the heel should be centered behind the ball of the foot. Many clients externally rotate their hip so that the back knee and toes are slightly turned out. This makes it difficult to stretch the lateral fibers of the gastrocnemius and soleus.

Dynamic Functional Flexibility

Once you've assessed your client's areas of hypermobility and hypomobility and used the tips to help your clients work on areas on hypomobility with static stretching activities, how do you put it together with dynamic functional flexibility activities? How can you work with your clients to find the balance of coordination, strength, muscular endurance and flexibility to help them in their everyday activities?

There are many ways to focus on this balance. Some of the exercise programs that are based on Eastern philosophies, such as yoga and tai chi, play with strength and flexibility in various positions. One of the benefits of these programs is that participants often feel they can move more easily in their everyday activities. The movement patterns in yoga and tai chi are usually slow, controlled and take the entire body through a broad ROM. To be successful in achieving a flowing style of movement and holding some of the positions requires a balance of flexibility, coordination, strength and endurance. These types of programs are examples of dynamic stretching.

If you choose to incorporate these types of movement patterns in your clients' exercise programs, please be aware of a few precautions. These programs emphasize feeling the movement and generally do not use music where movements must occur at a set pace and positions must be held a certain amount of time. Participants are encouraged to self-monitor and adapt positions as required. The emphasis is on doing what the body is ready to do rather than copying what the instructor and other participants are doing. One of the self-monitors is maintaining slow, relaxed breathing. Many clients use breathing to monitor aerobic intensity or use specific breathing techniques during strength training. They may confuse the breathing techniques used in these programs with slow, relaxed breathing which is quite different. When introduced to these types of exercises, they may push themselves too hard and experience pain and discomfort. However,as long as they correctly self-monitor their movements, they often show positive gains in flexibility.

In the types of exercise programs commonly found in the United States, functional flexibility is practiced by using correct body mechanics throughout the ROM of the exercises. As an example, when performing hip extensions (lifting the leg to the back), functional flexibility requires the person lift their leg without hyperextending their lower back. Participants often feel they get a better workout in the hip extensor muscles when they lift their legs higher. They do not realize this is true only if their spine remains stable. If they lift the leg higher in the back by increasing their lumbar curve, then they increase their risk of back injury rather than the strength and endurance in the gluteus maximus and hamstrings. Some of the spinal stabilization exercises focus on maintaining a neutral spine while performing various movements. When exercising the lower body, maintaining a neutral spine protects the back while helping develop functional flexibility in the legs.

When weight training with clients, do not use weight machines exclusively. Weight machines are excellent for helping someone isolate specific muscles and for working on strength and endurance in a relatively safe environment. However, movements are limited to the range and plane of motion that are built into the equipment. Once someone has reached basic strength and endurance levels on weight equipment, they can work on the same target areas with free weights. The first time someone moves from weight machines to free weights, they are often surprised at how much more stabilization they need and some of the asymmetries they may have when comparing the right side of the body to the left side. Someone who only practices biceps curls on weight equipment is usually limited to working in the sagittal plane. However, in real life, we lift things by bending our arms in more positions than directly in front of us. With free weights, we can practice our bicep curls in many different positions. By varying our positions and using full ROM in the elbow, we can address functional flexibility in our biceps, supinators/pronators and shoulder rotators.

How much the movements in all of these programs help us in performing our everyday activities depends on the instructor, participants and exercises they use. Generally, the more the movement looks like an everyday activity, the more likely we are to have some carry over from the fitness setting to real life. Doing squats with free weights looks more like sitting down in a chair than doing leg extensions with a machine. While both exercises are excellent for strengthening the legs, some people have to practice the exact activity to see improvement in their functional flexibility. Others find gains in their functional flexibility as long as the movement is somewhat similar to their everyday activities.

Not every movement in our fitness programs has to contribute to functional flexibility. Flexibility is only one of the five components of health-related fitness. However, to help prevent injuries, we should incorporate functional flexibility into our clients' overall fitness prescription. To help individualize a program, we reviewed some basic screenings for flexibility. For areas of hypomobility, be sure to include static stretches after the body is fully warmed up to help increase your client's ROM. For both hypomobility and hypermobility, be sure to include functional exercises that help maintain a balance of coordination, strength, muscular endurance and flexibility. You can address functional flexibility by using different types of movements such as those found in yoga and tai chi or by incorporating functional movements in your regular aerobic and weight training programs. By including functional flexibility into your exercise programming you'll help your clients avoid injury, while encouraging them to be their best.

Author's Bio:

Sharon Cheng is an AFAA master specialist, co-owner of Fitness By Definition, and has worked in the fitness industry for more than 15 years. She is a licensed physical therapist and works as the Director of Rehab and Fitness Services for All Saints Health System in Ft. Worth, Texas.