Exercise Safety

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Over Generalizations It is easy to denounce an exercise or movement as 'dangerous', particularly if an injury has occurred during its execution. When someone sustains an injury while performing a particular exercise, we should not assume that a particular exercise is necessarily a 'bad' exercise. Likewise, we should not judge a particular exercise or movement as 'bad' if an exerciser experiences pain during its execution before an injury has healed, allowing for proper rehabilitation to be administered. Trainers often tell their clients not to perform a particular exercise through full range of motion. Take for example allowing the elbow to travel behind the shoulders during a bench press or chest press. These guidelines may be appropriate for those with a Shoulder Transverse Adduction / Flexor Inflexibility and/or an Infraspinatus Weakness. However, this same advice is inappropriate for those with no biomechanical deficiencies relating to the structures in question. Perhaps a trainer was told by their client that their physician ordered them to avoid a particular exercise or a specific range of motion due to an orthopedic problem. More commonly, trainers offer these over-generalizations because their 'Cracker Jack' certification recommend such practices despite the ability of most people to safely perform these movements. Certainly, some individuals should not a perform a particular movement due to a recent injury or an orthopedic issue, but to suggest a movement is inappropriate for all people is an erroneous assumption. Livingston, CSCS (2004) explains, "The justification of contraindication is derived from the philosophy of training at the level of the lowest common denominator. There are very few exercises that should be contraindicated. There are lots of people who should not be doing certain exercises." Take for example, sprinting, or even running. These modes of exercise could be considered contraindicative for many people, yet we understand there are those individuals that are certainly capable of performing these activities relatively safely. We also can understand the need to prescribe these forms of exercise for those with particular fitness or sports performance goals. For this reason, we should not dismiss other exercises or activities as dangerous for all individuals. Certainly one can find numerous studies supporting the injurious effects of running or sprinting. One could even make the argument than nearly all runners or athletes that run have occurred an injury sometime in their careers. But are we to deem running contraindicative for these reasons? Although certain movements should not be performed by those with a current injury or even those with certain predispositions to certain orthopedic complications, for those with relatively healthy joints, these movements may actually decrease the occurrence of injury, particularly when the joint is moving through this particular range of motion, perhaps even inadvertently or subtly. Conversely, avoiding a movement or a particular range of motion during exercise may actually increase the risk of injury, particularly if the joint ever experiences greater load than what it is accustomed to through these particular ranges of motion, either in real world situations or in training. See example effects of range of motion restrictions: Avoiding knee lockout during squat, leg presses, etc. Lack of Vastus Medialis Involvement Potential weakness leading to patella tracking problems Avoiding full extension or abduction during shoulder presses Lack of Supraspinatus Involvement Increase potential of should injury Avoiding spinal extension under load Erector Spinae Weakness Degeneration of joint structures in spine (Nelson 1993) Greater venerability to low back injury (Nelson 1995) So what is an exercise instructor to do when working with a group? Instead of announcing to the class that a certain movement is 'bad', educate your class. With certain 'higher risk' movements, instruct those who have had certain knee or shoulder problems to do it one way (having them follow the advice of their physician) and have the remaining participants perform the movement through the fuller range. Typically restrictive guidelines given for injured individuals or those with biomechanical deficiencies are commonly misconstrued and unnecessarily recommended for orthopedically healthy individuals. Ironically, an injury-free individual may be more likely to injure themselves avoiding a movement they believe to be dangerous (full range of motion, locking out, etc.) when they inadvertently perform that movement, as compared to someone that implements that movement following sound training principles and adaptation criteria. The appropriateness of an exercise should be assessed on an individual case-by-case basis. See Common Biomechanical Deficiencies (below) and Dangerous Exercises Essay and Squat Safety. Causes of Injury Both extrinsic and intrinsic factors can increase the risk of injury. Extrinsic factors include training errors, faulty technique, poor environmental conditions, incorrect equipment and surfaces. Intrinsic factors include biomechanical deficiencies, including malignant of limbs, muscular imbalances, degenerative processes, and other anatomical factors (Crown LA, et. al., 1997). Biomechanical deficiencies (as those referenced below) may contribute to orthopedic injury when combined with other factors than may negatively effect joint integrity (e.g. hyper-mobility, structural weakness, insufficient adaptation of joint or muscular structures, acute or chronic overtraining, etc). See Adaptation Criteria. Sports Conditioning Athletes are always at risk of injury, whether it be during practice, in the weight room, or on the playing field. The reasons of injury vary and often happen unnecessarily. The failure to understand and implement fundamental training principles and adaptation criteria is largely to blame. A program that does not adequately prepare the athlete for the specific types of forces and stresses experienced on during the sport place athletes at risk. See Training Specificity and Resistance Training for the Reduction of Sports Injury. Programs that fail to incorporate movements that condition stabilizing muscles (joint stabilizers such as hamstrings and rotator cuff muscles), maintain ideal muscular balance, and correct biomechanical deficiencies unique to each athlete increase the risk of injury on and off the playing field. Using too much resistance or perform too many sets when athletes are first introduced to new movements or exercise variations are common training errors greatly increasing the risk of injury. Injuries can also be caused by poorly designed split and cross training programs (e.g. speed, agility, and strength training) as well as the over emphasis of higher-volume training programs. See Overtraining. The coach can introduce methods in which athlete's can customized a 'group program' to each athlete's unique abilities, results, and needs. Coaches must allow for proper adaptation to 'new' exercises, understand the benefits periodization techniques, implement program customization, and schedule adequate recovery periods for optimal recovery and progress. Also see Training Mistakes. Common Biomechanical Deficiencies Weaknesses Inflexibilities Postural Deficiencies The biomechanical deficiencies are listed for precautionary measures only so they may be identified and possibly corrected in attempt to prevent athletic injuries during exercise or physical activity. A physician may need to establish if a biomechanical deficiency is structural, muscular, neuromuscular, or due to some other pathology. The corrective exercises assume a muscular imbalance (flexibility and strength). Only a qualified physician should diagnose and give prescription for an existing injury. In some circumstances, an attempt to correct a biomechanical deficiency may irritate the injury and prolong recovery, particularly if certain exercises are initiated too soon after an injury has occurred. Even after the underlying biomechanical deficiencies have been improved, the injury may require the attention of a physical therapist under the advise of a physician to restore total functionality. See Injury Prevention Tidbits and Sports Injury First Aid. Controversial Exercises When introducing any new exercise, particularly exercise associated with higher risk, strict progressive adaption and caution should be practiced. For healthy individuals with no biomechanical deficiencies and sound training practices, many exercises considered controversial are relatively safe when performed correctly and may actually decrease the risk of injury. See Squats as an example. This is particularly true when an even greater stress from daily activity, sports, other conditioning exercises will be encountered. Sample Exercise Questioned Position Considerations Full squat Smith squat Leg press Depth Jump Knees flexed, also knees beyond toes Hips flexed, then Spine flexed Knees extended (locked) Inflexibility Gluteus Maximus Dorsiflexion Weakness Hamstring Erector Spinae Abdominal Vastus Medialis Biomechanical Analysis Squat Smith squat Full Range of Motion Joint Adaptations Lateral Step-up Alternating Step-down Knee extension during knee medial or lateral rotation. Rotary Force during Squats Certain activities such as skiing require these movement combinations. Straight leg dead lift Stiff leg dead lift Cable Row Standing hamstring stretch Spine flexed Inflexibility Hamstrings Weakness Erector Spinae Biomechanical Analysis Straight leg dead lift Cable Row Joint Adaptations Lower Back Recuperation Bench press Chest press Depth Push-up Elbow below, or behind shoulders Shoulders extended / horizontally extended Back Hyperextended Elbow extended (locked) Posture Protracted Shoulder Weakness Infraspinatus Biomechanical Analysis Specific Adaptations Joint Adaptations Upright row Narrow grip Internally rotated shoulder while shoulder abducted and flexed Inflexibility Internal Shoulder Rotation Biomechanical Analysis Upright Row Safety Rear pull downs Behind neck shoulder press Lever Fly (on pec deck) Externally rotated shoulder while shoulder Abducted Inflexibility Internal Shoulder Rotation Posture Winged Scapula Military press Shoulder press Elbows below shoulders Abducted shoulders Elbow extended (locked) Weakness Supraspinatus Biomechanical Analysis Full Range of Motion Joint Adaptations Bench press Military Press Lying leg curl Lower back arched Spine hyperextension Posture Lordosis Inflexibility Hip Flexor Biomechanical Analysis Lower Back Review of Literature Hamstring Active Insufficiency Sit-up (particularly straight leg) Roman chair sit-up Decline sit-up Lying leg raise Hip extended during Hip flexion Inflexibility Hip Flexor Weakness Abdominal Biomechanical Analysis Incline Sit-up Plyometrics Ballistic movements Recommendations Adaptation Criteria Crown LA, Hizon JW, Rodney WM, (1997) Musculoskeletal Injuries in Sports, The Team Physician's Handbook, Mosby, 2: 361-370. Livingston S (2004). Contra-indicated People Versus Contra-indicated Exercise, Society of Weight Training Injury Specialists (SWIS) Symposium.