Home of Sports Medicine and Exercise Physiology

“I’ve started running, but my knees are killing me. I used to run for miles, but now I can’t. Any advice?”

It’s great to strengthen your heart, but why derail nature’s transportation system in the process? With each step, you pound your joints with about four times your weight. Ease into it: Start by walking 30 minutes a day and doing strength training a few days a week. Build up the muscles around your knees with exercises such as lunges or squats. Plus, weight training can help you lose weight, so you put less strain on your knees. After a month, try running again, but don’t increase your mileage by more than 25% a week.
Crucial: Go to a specialty sneaker store to have your gait analyzed so you can find shoes with proper support. Add calcium, magnesium and vitamins C and D to your diet to help prevent osteoarthritis. And keep in mind that running on a treadmill or track can be easier on aching knees.

Among movement scientists and clinicians, there is often disagreement over the use of the terms kinesiology and biomnechanics. The word kinesiology is a combination of the Greek kinein meaning ((to move” and logos meaning “discourse.” Kinesiologists—those who discourse on movement—combine anatomy (the science of body stmcture) with physiology (the science of body function) to produce kinesiology, the science of movement of the body.
Kinesiology has long been used an umbrella term to describe any form of anatomic, physiologic, psychological, or mechanical human movement evaluation. Therefore, kinesiology has been used by several disciplines to describe many different content areas. A class in kinesiology may consist primarily of functional anatomy at one university and strictly biomechanics at another. Typically, a kinesiology course has been part of college curricula in physical education, exercise science, athletic training, and physical therapy programs. These courses usually focus on the musculoskeletal system, movement efficiency from an anatomic standpoint, and joint and muscular actions during simple and complex movements. A successful student in a kinesiology course could identify discrete phases in an activity, describe the segmental movements occurring in each phase, and then identify the major muscular contributors to each joint movement. Thus a kinesiologic analysis of the movement of a vertical jump would be as follows: The movements would be hip extension via the gluteus maximus and hamstrings, knee extension via the quadriceps femoris, and plantarflexion via the gastrocnemius-soleus complex. Such an analysis is considered qualitative because it involves the observation of movement and identification of the muscular contributions to that movement.

In the last 30 to 40 years, biomechanics has been developed as an area of study within undergraduate and graduate curricula throughout the world. The contents of biomechanics include a marriage of the areas of applied physics or mechanics and biology. Mechanics, the study of the effect of forces on an object and the resulting motions, is used by engineers to design and build structures or machines because it provides the tools for analyzing the strength of structures and methods for predicting and measuring the movement of a machine. Since it is natural to apply mechanics to the movements and structures of living organisms, the term biomechanics was created.
A biomechanical analysis evaluates the motion of a living organim and also may examine the forces responsible for the observed motion. Biomechanical analyses can be qualitative or quantitative, whereas a kinesiologic analysis would be strictly qualitative. Thus a biomechanical analysis of the vertical jump might include a qualitative description of the movement (similar to the kinesiologic analysis) in addition to the following: measurement of the forces between the person’s feet and the floor: quantification of the joint angles at the hip, knee, and ankle; calculation of the joint forces acting at each joint; and the amount of muscle activity in specific muscles.
Each of the posts in this series includes biomechanical analyses of a specific activity, since each describes certain movement characteristics and muscle actIvity both quantitatively and qualitatively, as available in the literature. More research is necessary before the biomechanics of even sport are fully understood. Clinicians today typically have several measurement tools—isokinetic/isovelocity dynamometers, electromyography (EMG) units, goniometers, and video systems—that enable them to conduct biomechanical analyses daily within the rehabilitation environment. A thorough understanding of the biomechanics of injury mechanisms, aspects of individual sports, and treatment interventions is crucial to providing the standard of care expected in today’s sports medicine environment.

Human movement has long fascinated scientists, clinicians, philosophers, and artists. Some of the greatest minds in history have expressed an interest in describing and understanding human motion:’ The famous Greek philosopher Aristotle (384—322 B.C,) the Roman physician Galen (13 1—201 A.D.), the brilliant Leonardo da Vinci (1452—1519), and Italian scientist Giovanni Borelli (11608—1679) all provided detailed and insightful descriptions of human movement and functional anatomy. Although these descriptions were purely qualitative, the astute observations and attention to detail were similar many ways to modem biomechanics.
The similarities lie in the fact that their descriptions were rooted in a desire to better understand the human body as a whole, either from a biologic perspective or from an artist’s need to better represent human movement in paintings and sculpture. In either case, human movement analysis was used as a tool to provide better understanding of the questions at hand.
The dawn of modern biomechanics coincided with the development of measurement tools that allowed the analyses to become quantitative. The advent of the motion picture camera allowed scientists and photographers to investigate details of human motion that go beyond the capacity of the naked eye. In addition, innovative techniques for recording ground reaction forces and displacements, as well as more precise time measurements, facilitated some of the first studies that could be classified as biomechanics or even exercise science. Nobel prize winner A. V. Hill, a physiologist who many consider to be the “father” of modern exercise science, integrated physiologic and mechanical measures to provide valuable insight into the mechanics of muscle contraction, energy expenditure, and the efficiency of distance running and to create the first description of the velocity curve in sprinting. Wallace Fenn, one of Hill’s students in physiology, used similar instrumentation to pioneer calculation of the work done by the body against gravity as well as an estimation of the work done by individual segments. Herbert Elftman, a biologist, conducted the first true “biomechanics study using mechanical principles to estimate the contribution of muscles during the motion sequences recorded by Fenn. The preceding works again demonstrate that biomechanics can best be described as an interdisciplinary tool used by physiologists, engineers, biologists, and artists.
The advancement and widespread use of high-speed film in the 1960s and early 1970s facilitated publication of biomechanical research studies related to sports. Refinement in instrumentation techniques using newly available microelectronics devices resulted in improved measurements of force, acceleration, muscle activity, and physiologic parameters. For the first time, detailed descriptions of the movements, forces, and metabolic characteristics of athletes during different activities were made available to clinicians and researchers. Thus the fields of sports medicine and sport science began to grow and assemble a body of literature and associated professional societies. College curricula for students in physical therapy, coaching, medicine, physiology, and exercise science started to include classes in biomechanics and kinesiology. The study of human movement became an integral part of the preparation of professionals in many areas.
Over the last 25 to 30 years, the proliferation of sports medicine and sport science literature related to human movement has been phenomenal. For the sports medicine professional, modem biomechanics research can be especially helpful in understanding injury mechanisms, prescription of rehabilitation programs, performance enhancement, and improved athletic equipment. However, the level of detail in many biomechanics research studies may be beyond the needs of the clinician. Thus the clinician has the daunting task of sorting through the immense amount of research literature generated each year and deciding what is relevant for improving the level of care given to a patient or athlete following an injury. Hopefully, this text will be helpful in providing both an overview of the detailed biomechanics associated with a broad range of sports and suggested techniques for effective rehabilitation.

Source: Shamus, Eric – Shamus, Jennifer. ” Sports Injury; Prevention and Rehabilitation”. McGrow-Hill Companies. 2001

If sensitive knees are preventing you from doing kneeling exercises, Fila’s new Knee Pad Yoga Capri ($55; fila.com) might help. The thin, built-in cushioning kept our tester’s knees comfy as she did everything from bent-knee push-ups to Cat/Cow poses. Wear the pants whenever you get down on the ground, like gardening or playing with kids. —by Jessica Cassity/Prevention magazine

Most people who get carpal tunnel syndrome have jobs or hobbies that involve repetitive motion of the hand, wrist, or arm. I also applies to athletes who perform sports that include repetitive motions such as golf, tennis, and similar sports that put pressure on the wrist.
Cause: Repeating the same hand, wrist, and arm movements hour after hour, day after day is the primary cause of carpal tunnel syndrome. When force is used at the same time, carpal
tunnel syndrome becomes even more likely. The disease develops when the repeated motion inflames the tendons in the wrist. This inflammation puts pressure on the nerve that runs through the carpal tunnel (a passage through the bone and ligament in the wrist).
Incidence: Carpal tunnel syndrome often occurs among workers who have jobs that involve repetitive lifting or finger and wrist motions, and sometimes in athletes that don’t perform proper stretching exercises and irresponsibly exhaust their body. People who work with computers are likely candidates too. Carpal tunnel syndrome also occurs among amateur and professional musicians, people who do needlework or other crafts involving the fingers and wrists, and food-service workers who chop and cut.
Women who are pregnant, are taking birth control pills (oral contraceptives), or are in menopause (the life stage when they stop menstruating) are more prone to get carpal tunnel syndrome. Conditions such as diabetes, thyroid disease, rheumatoid arthritis, and Lyme disease have also been linked to carpal tunnel syndrome. In addition people who weigh more than they should, do not get enough exercise, or have bad posture are at risk.
Symptoms you are likely to notice: Numbness or tingling in the hands, especially at night, is a major symptom. Hands may also become “clumsy:’ Some people feel pain in their hands, wrists, arms, or shoulders.

Symptoms your physician may observe: The physician will ask you to bend back your hand at the wrist to test the flexibility of the wrist. You may need to squeeze a device that measures the strength of the hands and fingers. Another test for the syndrome involves holding the hands together as if praying, but upside down. After a few moments the physician will ask about numbness or tingling. He or she will also tap the hands and arms lightly and ask about tingling sensations at that time. These tests will determine whether the problem is caused by carpal tunnel syndrome. They will also show the seriousness of any damage.
In some cases the physician may do a nerve conduction study, or electromyography. For this test he or she inserts needles at several places on the patient’s arm, and then runs a very low voltage of electricity through the needles. The test shows the location of any nerve damage.
Treatment options: The treatment for carpal tunnel syndrome begins with rest. The patient will need to give up activities that strain the hands and wrists temporarily. Moist heat and cold packs often help to ease the pain. The physician may prescribe anti-inflammatory drugs such as ibuprofen or naproxen for pain relief and to reduce inflammation. If there is a lot of pain and oral anti-inflammatory drugs do not help, the physician may inject cortisone. However, cortisone can cause unwanted side effects. The doctor may recommend sleeping with a wrist splint on the injured wrist. In some cases surgery may be necessary to relieve pressure on the nerve in the carpal tunnel. Most physicians, however, recommend surgery only when other treatments do not help. The physician will probably send the patient to a licensed physical therapist, who will help rebuild weakened muscles and teach stretching exercises designed to make arms and wrists more flexible.
Before returning to the activity that caused the injury, a patient needs to make lifestyle or work changes that will prevent reinjury. If you use a computer, for example, it is important to make sure it is set up correctly and that you are using good keyboarding techniques. It is also important to take frequent breaks.

Stages and progress: The longer carpal tunnel syndrome goes untreated the more extensive the nerve damage will be. The muscles of the shoulders, arms, and hands become weak, and you may develop other repetitive strain injuries.
Prevention and risk factors: Carpal tunnel syndrome is usually caused by rapidly repeated motions. When the wrist is held in an awkward position or force is used during such activities, the likelihood of injury increases.

Four things can be done to reduce the chances of getting carpal tunnel syndrome: (1) Learn how to do repetitive tasks in ways that will not strain the hands, wrists, and arms.

(2) Take frequent breaks when doing repetitive tasks.

(3) Use only as much force as is absolutely necessary to get a job done.

(4) Do stretching exercises to keep muscles flexible before beginning and after finishing a task. If you spend more than about an hour at a task, also do stretching exercises during breaks.