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The following are my regularly updated notes from my presentations to
the North Carolina Chiropractic Association 1st Annual Sports
Symposium, July, 1999 and the Maryland Chiropractic Association,
March, 2000.
See Active Release Techniques® and
Graston Technique for more information
on injury care and prevention.
See:
Ames, R. "Weightlifting Injuries and Their Chiropractic Management:
A Clinical Review. Part 1: A Clinical Framework for Management"
Journal of Sports Chiropractic and Rehabilitation, 12(2):65-70,
June 1998
Ames, R. "Weightlifting Injuries and Their Chiropractic Management:
A Clinical Review. Part 2: Injury Management and Overview"
Journal of Sports Chiropractic and Rehabilitation, 12(2):71-81,
June1998
Bauer, Jeffrey, Fry, Andrew, Carter, Cory. "The Use of
Lumbar-Supporting Weight Belts While Performing Squats:
Erector Spinae Electromyographic Activity" Journal of Strength and
Conditioning Research 13(4): 384-388, 1999.
Bemben, Michael and McCalip, Gregory. "Strength and
Power Relationships as a Function of Age" Journal of Strength
and Conditioning Research, 13(4): 330-338, 1999.
Masterson, Gerald. "The Impact of Menstrual Phases on Anaerobic
Power Performance in Collegiate Women" Journal of Strength and
Conditioning Research, 13(4): 325-329, 1999.
Reeves RK, Laskowski ER, Smith J. "Weight Training Injuries:
Part 1: Diagnosing and Managing Acute Injuries" Physician and
Sports Medicine 26(2):67-83, February, 1998.
Reeves RK, Laskowski ER, Smith J. "Weight Training Injuries: Part 2:
Diagnosing and Managing Chronic Conditions" Physician and Sports
Medicine 26(2):54-63, February, 1998.
Weinert, Dan. "Scapular Stabilization Exercises for Weightlifters"
Journal of Sports Chiropractic and Rehabilitation,
13(4): 139-144, 1999.
Whitting, W, Rugg, S., Coleman, A., Vincent, W. "Muscle Activity
During Sit-ups using Abdominal Exercise Devices" Journal of
Strength and Conditioning Research, 13(4): 339-345, 1999.
TYPES OF STRENTH TRAINING
Five categories of weight training: Olympic weightlifters, powerlifters,
bodybuilders, amateur and elite athletes who use weights for training,
and injured athletes or nonathletes in need of rehabilitation.
PSM: Circuit, Focused Weight training, Bodybuilding, Powerlifting,
Weightlifting
Types of Strength Training and Competitions:
1. Training for a sport with weights
2. Rehabilitation
3. Recreational strength training
4. Weightlifting
1896, only superheavyweights
Launceston Eliot lifted 71kg in the one hand lift
Viggo Jenson and Launcestion Elliot both lifted 111.5kg in the two hand lift,
but Jenson awarded victory because he did not move his feet.
1928 winning lifts in snatch 107.5kg (236.5lb) and C&J 142.5 (313.5lb)
1996 winning lifts in snatch 197kg (435lb) and C&J 260kg(573lb)
All weight categories changed in 1992
Prior to 1995 world championships 856 male weightlifters given doping tests
and 62 from 31 countries tested positive for steroids.
Wallechinsky, David. The Complete Book of the Summer Olympics Little, Brown
and Company Boston 1996.
International Weightlifting Federation founded in 1905.
The IWF recognizes two events, which must be done in competitions in the
following order: a) the two hands snatch (snatch), and
b) the two hands clean and jerk (C&J). The overall winner of any weightlifting
competition is the athlete who lifts the highest combined amount of weight
in the snatch and C&J (i.e., the heaviest weights successfully lifted in
each event are combined) . This combined score is called the "Total." While
awards are given at major competitions for each event as well as the
Total, recognition in the sport of weightlifting goes to the athlete who
lifts the greatest total weight in competition. The minimum age for
participation in the Olympic Games and the World Championships for men is
fifteen.
There are eight (8) categories for men - juniors and seniors: 56kg to 105kg+
There are nine (7) categories for women: 48kg - 75kg+
World Record Snatch: Men: 467.5 Women: 280.5
World Record Clean and Jerk: Men: 577.5 Women: 346.5
5. Bodybuilding
1938: Mr. America first contested- Bert Goodrich
Mr Olympia
Larry Scott 1965-66
Sergio Oliva 1967-69
Arnold Schwarzeneggar 1970-75
Franco Columbo 1976
Frank Zane 1977-79
Arnold Schwarzeneggar 1980
Franco Columbo 1981
Chris Dickerson 1982
Samir Bannout 1983
Lee Haney 1984-91
Dorian Yates 1992-97
Ron Coleman 1998-99
6. Powerlifting
First National Championship in 1964 and first world championship in 1971
Squat: 1000+
Bench: Almost 800
Deadlift: over 900
Total: 2463 by Ed Coan in 242lb. class, Squat: 1003 Bench: 573 DL:887
7. World Strongest Man and Highland Games
Circuit Training: Rapid transition from one muscle group exercise to
the next with 15-30 seconds rest between exercises. Weights used
are 40% - 60% of 1RM. Strength and aerobic gains are modest.
Risk of injury is short rest period.
Focused Weight Training: Machines and free weights are used as part
of an overall fitness program. Overtraining (ignoring pain from workouts)
is most common reason for injury.
Bodybuilding: Weights used are 80% - 100% of 1RM, 1 to 100 reps.
Risk is for both acute and chronic (overuse) injury. There is the
problem of ergogenic aids like anabolic steroids, human growth hormone
and many nutritional supplements of unknown value.
Weightlifting: Snatch and Clean and Jerk. Acute injury can occur due
to loss of control and chronic injury due to overuse.
Powerlifting: Squat, bench press and deadlift.
INJURY RATES
45 million Americans weight train regularly. Serious injuries are relatively rare.
In 1986 43,400 ER visits out of 5.6 million for all sports (<1%).
In 1995 56,400 ER visits out of 5.4 million for all sports (1%).
Recreational Injury Rates
1. Lombardi, V Recreational Weight training Injuries & Deaths: Trends Over The Most Recent Decade In The U.S. Medicine and Science in Sports and Exercise S98, 27(5).
U.S. Consumer Product Safety Comission Incident data files for 1982, 1991, 1992 analyzed.
Young males 15-24y.o. accounted for most of the injuries. Muscular strains and ligamenous sprains most common.
Majority of injuries in children were to toes, finger, head and face
Majority of injuries in adolescents and adults were to lower and upper trunk and shoulder
One dozen deaths with recreational weight training between 3/91 and 4/92.
11 cases involved males dying of asphyxia due to barbell compression of the neck
or chest as they performed heavy, home bench presses without a spotter.
2. Some 986 recreational fitness subjects were followed for 3 months to study
injury patterns. Runners had the most injuries, followed by those in team
sports and individual sports. Non-running cardiovascular fitness activities
and resistance training had the lowest rates of injury. Free weight activities
had slightly fewer injuries than machine training.(Requa)
Novice weightlifters can remain injury free- injury rate 0.oo17 per
100hours compared to basketball (0.03), track and field (0.57), gymnastics
(0.044) and football (0.10). (Stone)
Powerlifting Injury Rates
Brown and Kimball in 1983 found that 39.4% (28 0f 71) adolescent
powerlifters entered in a teenage powerlifting championship (ages 14-19)
sustained injuries during training. High rate of injury may have been
result of poor supervision.
Football Injury Rates
Risser et al in 1990 in a retrospective study found on 7.6% (27 of 354) of
adolescent football players in a supervised program sustained injuries.
Zemper in 1990 found only a 0.3% rate of injury in a 4 year study of a
national sample of college football players who trained under supervision.
There are no risk factor studies of weight training, but poor technique, lack
of supervision, skeletal maturity, steroid abuse (overuse, poor equipment)
are recognized as contributing factors.
Skeletal maturity: American Academy of Pediatrics issued guidelines for
weight training in children. They call for proper supervision and
advise that adolescents reach Tanner stage 5 before participating in
vigorous weight training.
Conditioning Injury Rates
An athlete-exposure is one athlete taking part in one practice or
competition where he is exposed to the possibility of being injured.
Over four years there were 742,720 A-E for the 10,908 players in the
sample. During the period of the study there were 38 time loss
injuries occurring during weight training resulting in an injury rate
of 0.13 injuries per 1000 A-E or 0.35 injuries per 100 players.
About 40% of those injuries involved the lower back.(Zemper)
Weightlifting Injury Rates
Competitive adolescent Olympic weightlifting in Britain
(Schoolboy Championship) has been staged annually for 18 years and has
involved some 54,600 competition lifts and 54,600 heavy warm-up lifts.
In this period one boy suffered a concussion when he fell onto a weight
after losing control and another was bruised when he dropped a weight
onto his upper back. In neither case has there been any evidence of
a long-term consequence. The serious injury from a fall represents
roughly 0.0018 injuries per 100 hours.(Hamill)
Hamill, B. "Relative Safety of Weightlifting and Weight Training" Journal
of Strength and Conditioning Research 8(1):53-57, 1994.
Requa, R., et al. "Injuries in recreational adult fitness activities."
American Journal of Sports Medicine 21:461-467, 1993.
Zemper, E. "Four-year study of weight room injuries in a national sample
of college football teams" National Strength and Conditioning Association
Journal 12(3):32-34, 1990.
TYPES OF INJURIES
A. Acute: Strains, Sprains, Fractures, Ruptured discs, Nerve damage.
1.Causes: Barbell or platform defects, improper footwear, collisions
with the bar, poor technique, failure to properly warm-up, and
rapid weight loss.
2.Typically occur due to athlete losing concentration, attempting to
perform beyond his capabilities, returning to training before being
completely rehabilitated, poor coaching.
B. Chronic: Tendonitis, bursitis
1. Typically the result of poor technique, use of high volume or high
intensities for too long a period, poor choice of exercises.
It has been shown that the stress placed on tendons during a maximum
contraction is about 30% of the max tensile strength of the tissue.
This leaves a >200% safety margin.
Stone, M., et al. "Injury Potential and Safety Aspects of Weightlifting
Movements" Strength and Conditioning 16(3):15-21, 1994.
GENERAL CAUSES OF INJURIES
Title Weightlifting injuries and their chiropractic management: a
clinical review. Part 1: A clinical framework for management In Journal
of Sports Chiropractic & Rehabilitation 1998 Jun 12, 2, p. 65-70,
105-6 (28 ref) Author Ames R.
Abstract The sports chiropractor is a
primary contact practitioner with a special interest and training in the
diagnosis, treatment, and rehabilitation of athletes with injuries. Weight
training is common in the overall program of many athletes; therefore, it
is probable that the sports chiropractor will see these athletes as patients.
This presentation acquaints the sports chiropractor to the background,
diagnosis, and management of a group of injuries common to Olympic
weightlifters, powerlifters, bodybuilders, amateur and elite athletes
who use weights for training, and injured athletes or nonathletes in need
of rehabilitation. The general causes, mechanism of injury, and desirable
attributes of both the weight-training program and the nutritional needs
of the athlete are covered. The total range of management options available
to the sports chiropractor is extensively outlined. Strategies for prevention
of injuries, based on interactions with the coach and other health
professionals, are presented.
External factors (no control)
Equipment defects
Collisions
Bar hits
Gym climate
Poor program development: Exceeds musculoskeletal tolerance of athlete
Has control:
Insufficient warm-up
Overstrain
Poor technique
Quick body-weight change
Poor concentration
Insufficiently healed injury
Insufficient recovery
Poor nutrition/substance abuse
ACUTE INJURIES
Title Weight training injuries. Part 1: Diagnosing and managing acute
conditions In Physician and Sportsmedicine 1998 February 26, 2,
p. 67-83, 96 passim (45 ref) Author Reeves RK; Laskowski ER; Smith J.
Musculoskeletal Injuries
Ligament sprains
Grade I: Pain on palpation, solid end-point on examination
Grade II: Pain on palpation, mild laxity compared to contralateral
ligament
Grade III: Significant laxity without a solid endpoint (gross instability)
Medial and lateral collateral knee ligament sprains may occur during squats,
leg presses, lunges. Complete ligament disruption is uncommon but Freeman
and Rooker reported that bodybuilder on steroids presented with spontaneous
ACL rupture.
Medial meniscus tears associated with hamstring curls and deadlifts
Muscle strains
Grade I: Pain on palpation, little or no weakness, no palpable
defect or asymmetry.
Grade II: Significant pain and mild weakness
Grade III: Possible muscle asymmetry with a palpable defect,
significant weakness.
Hamstring and lower back strains are common.
Muscle ruptures and tendon avulsions can occur:
Patellar tendon rupture- eccentric part of jerk; squat; bottom of clean
Grenier, R. and Guimont, A. "Simultaneous bilateral rupture of the quadriceps
tendon and leg fractures in a weightlifter. American Journal of Sports Medicine
6:451-453, 1983.
Nisell, R. and Ekholm, J. "Joint load during the parallel squat in
powerlifting and forces of in vivo bilateral quadriceps tendon rupture"
Scand J. Sports Science 8:63-70, 1986.
Bilateral quadriceps muscle/tendon (squat - Mechician)
Biceps Rupture (Powerlifter Steve Wilson)
Due to the initial pull of the dead lift. Distal rupture off the radial
insertion.
D'Alessandro, D., et al. "Repair of Distal Biceps Tendon Ruptures in
Athletes" American Journal of Sports Medicine 21(1):114-119, 1993.
Pectoralis Injuries: Pectoralis major muscle/tendon
(Bench Press - Fried)
Pectoralis injuries are usually due to ballistic movement, rapid descent,
going for max imum lifts week after week.
Butcher, J., et al. "Pectoralis Major Rupture: Ensuring Accurate Diagnosis
and Effective Rehabilitation" Physician and Sports Medicine
24(3):37-44, 1996.
Rupture of pectoralis major muscle was first reported in 1822 and
was believed through the 1970s to be a rare injury. The injury most
commonly occurs performing the bench press. A 31YO male bodybuilder
presented with pain in the right upper pectoral region. He reported
that 1 week earlier he had felt a popping, tearing sensation in the
right pectoral area while performing the BP at 275lb. PE revealed
ecchymosis over the proximal right medial upper arm and pectoral area.
The area was tender to palpation and revealed asymmetry with an obvious
defect. Right shoulder ROM was limited and painful. Muscle strength
was decreased. Surgery used multiple nonabsorbable sutures to secure
the tendon to the remnant insertional tendon tissue. The tear is more
likely to occur during the eccentric phase of the lift.
Reut, R., et al. "Pectoralis major rupture" Physician and Sports Medicine
19(3):89-96, 1991
The main causative factor of pectoralis major tears is the fatigue
of the muscle due to incomplete recovery from overtraining.
Only five cases of triceps tears were found. No cases of deltoid tears
found.
Reynolds, E., et al. "Pectoralis Major Tears: Etiology and Prevention"
Chiropractic Sports Medicine 7(3):83-89, 1993.
Wolf, S., et al. "Ruptures of the Pectoralis Major Muscle" American
Journal of Sports Medicine 20(5):587-593, 1992.
Triceps tendon avulsion with radial neuropathy
Pelvic avulsion of ASIS - sartorius muscle contraction with forceful
hip extension (non-operative)
Ischial apophysis and hamstring avulsions with deadlift, squats and
hamstring curls.
Capsular ligament sprains
Ankle, wrist, costotransverse/vertebral joints
Costovertebral - lifter attempts to stabilize falling weight or
valsalva maneuver (Ames)
Hand Injuries
Torn calluses and blisters
Dislocations
1. Shoulder (posterior/inferior) - snatch - often self relocate
2. Elbow (Distal Radial Epiphysis Injuries)- medial dislocation of the
humerus from the olecranon - Overhead press or "catch" in snatch -
closed reduction
3. Wrist - Distal Ulnar Radial Dislocation
A 23YO woman injured her right wrist holding a weight lifting bar with
the forearm in supination when she was pushed from behind. She heard
a snapping noise, experienced sudden pain and could not move her wrist
without severe pain. Exam showed a tender prominence on the anterior
surface of the wrist just medial to the flexor digitorum superficialis
at the level of the distal radio-ulnar joint. Paresthesia was reported
in the median nerve distribution. Radio-carpal and carpal motion were
restricted. The lateral X-ray showed an anterior displacement of the ulna.
Francobandiera, C., et al. "Distal radio-ulnar joint dislocation, ulna
volar in a female bodybuilder" Medicine and Science in Sports and Exercise
22(2):155-158, 1990.
4. Wrist (lunate)
5. Patella (Ames) - squat/leg extension - more common lateral than
medial - often self relocate
Fractures
1. Clay-shovelers fracture - From bar while holding weight for squat.
2. Bilateral radius and ulna with loss of control of clean and jerk.
3. Scaphoid fracture with bench press (17 year old while attempting 430lb
bench press)
Reider, B., et al. "Scaphoid Waist Fracture in a Weight Lifter:
A Case Report" American Journal of Sports Medicine 21(2):329-331, 1993.
4. Second rib fracture associated with bench press
A 34 YO male complained of stabbing pain in left pectoral and rhomboid
muscles after benching 150lbs and was aggravated by lifting with his left
arm and with coughing. The pain lasted two weeks. PE revealed palpatory
tenderness over the left second through fifth ribs posteriorly. Muscle
testing of the left pectoralis major produced sharp pain. Active left
shoulder ROM was normal as were all neurological and orthopedic tests.
X-rays showed fracture of posterior aspect of left second rib.
Goeser, C. and Aikenhead, J. "Rib fracture due to bench pressing"
Journal of Manipulative and Physiological Therapeutics 13(1):26-29, 1990.
5. Talar dome fracture associated with squatting
6. Acute compression or burst fracture of the spine (Ames) -
missed lift in which lifter has fallen under the weight.
7. Avulsion fracture at the elbow (tricep avulses the olecranon)
8. Avulsion fracture at the knee (patella tendon avulses the tibial
tuberosity)
9. Avulsion fracture at the spine (erector spinae/quadratus lumborum
avulses the tranverse process) (Ames)
10. Acquried or traumatic spondylolysis most common at L5 - any adolescent
who has developed LBP that is unilateral, localized and increased in
intensity upon hyperextension and sitting/standing lifts should be examined
for this condition.
Acute Medical Events
Tremendous BP elevations as high as 480/350 mm Hg. MacDougall et al
also studied BP responsesin several lifting situations and found that BP
elevations were similar across contraction types (eccentric, concentric
and isometric) when intensity was controlled. Narloch and Brandstater
demonstrated that slow exhalation during the strain phase of a lift
significantly reduces BP elevation
(i.e., avoid valsalva).
Rhabdomyolitis
Disintegration or dissolution of muscle, associated with excretion of
myoglobin in the urine. can be life threatening because of the potential
for acute renal failure and electrolyte abnormalities. Creatine kinase
elevations to 76,000 IU/L have been reported. Treatment involves aggressive
hydration, urine alkalization and brisk diuresis.
Acute compartment syndrome
Progressively severe muscle pain following strenuous workouts,
especially if eccentric exercises were involved. Cardinal signs of
acute compartment syndrome are pain an pressure in a muscle or muscle
compartment, pain with stretching of that muscle, paresis and paresthesias.
A pulse may or may not be palpable. Compartment pressures should be
measured is suspected. Fasciotomy ofr pressure relief must be performed
in a timely manner to minimize permanent nerve and muscle injury.
Quadriplegia
26 Y.O. woman, in good health, experienced in weight training performed
rowing machine warm-up, leg extensions, leg curls, butterfly and behind
the neck pull downs and stretching. Total time 20 minutes. After 5 minutes
she noticed gradual onset of tingling and numbness throughout her body
beginning in the shoulder area and accompanied by an inability to move
any of her extremities. About ten minute later she was totally paralyzed.
She was taken to the ER. Exam showed weakness in right upper extremity
and no motor function in the left upper extremity or either lower extremity.
Lab work, X-rays, CAT scan, arteriogram negative. Cause of spinal apoplexy
unknown.
Shea, J. "Acute quadriplegia following the use of progressive resistance
exercise machinery" Physician and Sports Medicine 14(4):120-124, 1986.
· Aortic dissection - 4 associated with history of steroid abuse and
hypertension
· Acute radiculitis and possible increased risk for cervical and lumbar
disc herniation
· Effort thrombosis
· External iliac artery stenosis
· Myocardial Infarction
· Pulmonary Embolism
· Spontaneous pneumothorax
· Stroke
· Subarachnoid hemorrhage
Death
One dozen deaths with recreational weight training between 3/91 and 4/92.
11 cases involved males dying of asphyxia due to barbell compression
of the neck or chest as tey performed heavy, home bench presses
without a spotter. (Lombardi)
Per Spero Tshontikidis: coaching 15 years, only serious injuries if
athletes not coached.
Loss of control of bar with thumb under grip (16 year old kid) 370lb.
onto chest (fell 8 - 10 inches). Spotters didn't get it. Kid ok.
CHRONIC INJURIES
Title Weight training injuries. Part 2: Diagnosing and managing chronic
conditions In Physician and Sportsmedicine 1998 Mar 26, 3, p. 54-63, 73,
85-6 passim (37 ref) Author Reeves RK; Laskowski ER; Smith J.
Abstract
The repetitive nature of weight training and the often heavy loads involved
provide fertile ground for chronic injuries. Common chronic injuries include
rotator cuff tendinopathy and stress injuries to the vertebrae, clavicles,
and upper extremities. In addition, muscle hypertrophy, poor technique, or
overuse can contribute to nerve injuries such as thoracic outlet syndrome or
suprascapular neuropathy. Chronic medical conditions that are known to occur
in weight trainers include vascular stenosis and weight lifter's cephalgia.
Management of chronic problems will vary by condition, but relative rest and
correction of poor technique are important for many.
Tendon and ligament Injuries
Can occur at insertion, mid-tendon, muscle-tendon junction (Ames)
Common areas:
· Quadriceps tendon at the patella, patella tendon at attachment
to patella or tibial tuberosity (Jumper's knee- rapid uncontrolled
descent of squat)
Squats- little to no evidence that below parallel causes knee damage-
due to improper technique.
Squats do not affect rotational stability of knee and there is no
permanent stretch of knee ligaments
Medicine and Science in Sports and Exercise 6/89
OL and PL are no more susceptible to arthritic changes than general
population
Knee Wraps: Regulations allow 30cm of leg to be covered by wraps of
maximum 2 meter in length and 8cm in width in the unstretched state.
Not used en OL because it slows the movements down. Used in powerlifting
to increase the amount of weight lifted.
Proposed mechanisms:
1. Direct mechanical assistance- wrap exerts a force that extends the knee
2. The warming effect enhances blood flow.
3. Improved kinesthetic cuing, wherein the physical sensation of the wraps
on the kenes provides the lifter with better awareness of the knee angle,
thereby improving motor control and the ability to make adjustments in
technique.
4. Maintaining the patella in its proper track. Allows for greater
muscle force to be exerted.
5. Enhanced psychological state- increased feeling of security.
Wearing of wraps may cause chondromalacia patella because of overtightening.
(Harman)
Harman, E. and Frykman, P. "The effects of knee wraps on weightlifting
performance and injury" National Strength and Conditioning Association
Journal 12(5):30-35, 1990.
· Achilles tendon at calcaneus
· Pectoralis major at humerus
· Supraspinatus as is passes under the acromion. (Ames)
Tendonitis accounts for 3.5% ot 12% of weight training injuries.
Chronic excessive stress (too much weight and volume) and incorrect technique
AC Joint Injuries - From bench press, shoulder shrug, pads from standing calf
raise
Rotator Cuff Injury
Upright row, military press, Pec Dec - supraspinatus (look at subscapularis)
Sx: Diffuse aching of the shoulder, anterior chest and shoulder muscle
development is disproportionate to that of the scapular stabilizers.
The resultant inability of the periscapular muscles to stabilize the scapula
leads to scapulothoracic and glenohumeral dysfunction, which contributes to
inefficient force transfer through the shoulder.
Leahy, P. and Mock, L. "Altered Biomechanics of the Shoulder and
Subscapularis" Chiropractic Sports Medicine 5(3):62-66, 1991.
Narrow grip and pad on the sternum. This limits the amount of horizontal
abduction and prevents excessive strain on the anterior joint capsule.
Sigmon, C. and Tyson, A. "Preventing Shoulder Injuries by Modifying the
Bench and Incline Press" Strength and Conditioning 18(4): 52-53, 1996.
Weinert, Dan. "Scapular Stabilization Exercises for Weightlifters"
Journal of Sports Chiropractic and Rehabilitation, 13(4): 139-144, 1999.
- Blackburn position: arm is straight, abducted,
externally rotated and horizontally abducted while prone on ball.
- Scapular retraction with wide pull down
- Straight arm dip with scapular retraction
- Bench press with scapular retraction (no shrug or scapular elevation)
- Avoid upright rows to avoid impingement syndrome because of
internal rotation and flexion of the humerus causing impingement
of the supraspinatus.
- Push up with scapular retraction
- Ball push up with scapular retraction (patient standing,
ball on wall, patient's fist into ball with scapular protraction)
Anterior Shoulder Instability
Behind-the-neck lat pull downs (load in extreme external rotation);
bench press (shoulder hyperextension produces repetitive shoulder capsule
trauma and places excessive traction on the acromioclavicular joint;
behind-the-neck military presses (stress the shoulder capsule, rotator
cuff and inferior glenohumeral ligament.
Sx: Vague feeling of looseness or transient numbness of the arm.
Do instability tests like shoulder apprehension and relocation test
(pushing the humeral head posteriorly relieves symptoms of apprehension).
Capsular ligament sprains
Wrist in weightlifting - hyperextension of wrist strains intercarpal
ligaments and capsules
Radial-ulnar joint, intercarpal, carpal-metacarpal (Ames)
Lower Cervical Disc Injury
Injuries occurred almost exclusively during exercises where a) the
lower cervical spine was in a flexed position (the chin was protracted
and forward of the torso and b) a muscular force was produced in response
to a resistance, which further flexed the lower cervical spine (C5-C7).
This may cause trauma to the ligaments and discs resulting in referred
pain to a variety of soft tissue and peripheral locations.
If loading occurs when the neck is in this position, forces are
directed along the cervical spine's longitudinal axis, initially causing
compressive deformation. When the head is held in neutral position the
loading forces dissipate in lateral flexion, flexion or extension. Thus,
the cervical spine is able to sustain loading due to the ability of
the musculature, intervertebral discs and ligaments to absorb energy.
(Taylor)
Examples: Shrugs, Behind the neck presses, behind the neck pull-downs,
squat head position, calf (heel) raises.
Lefavi, R., et al. "Lower Cervical Disc Trauma in Weight Training:
Possible Causes and Preventive Techniques" National Strength and Conditioning
Association Journal 15(2):34-36, 1993.
Taylor, J. "Reducing the Risk of Neck Injuries Through Program Design"
National Strength Conditioning Association Journal 15(4):7-14, 1993.
Atraumatic osteolysis of the distal clavicle: insidious onset of
aching pain of the AC region that is exacerbated by weight training.
The pain may radiate to the deltoid or trapezium and is relieved by rest.
Frequently, patients report that pain disturbs their sleep.
Spondylolysis
Improper lumbar hyperextension during squats, military press and bench press.
36% of competitive weight lifters have a spondylolytic defect on spine films,
compared with 5% of the general population. Incidence of spondylo in
weightlifters (22 of 97 in one study) is higher than in the general
population.(4-7%). (Stone)
This is part of the reason the press was removed as an Olympic lift
after the 1972 Olympic Games.
Sx: Chronic unilateral low-grade back pain with exacerbation and radiation
to the ipsilateral sacroiliac joint. Lumbar extension/hyperextension
produces the pain. Patients have tight hamstrings and the stork test
is positive (patient balances on the leg on the pain side, then hyperextends
the lumbar spine and rotates the trunk toward the symptomatic side.
The test, which unilaterally loads the posterior elements, is positive if
the maneuver reproduces the pain).
Journal of the National Strength Conditioning Association 2/84
Granhed, H. and Morelli, B. "Low back pain among retired wrestlers and
heavy weight lifters" American Journal of Sports Medicine 16:530-533, 1988.
Spondylolisthesis
Slippage of L5 on S1 is most common in isthmic spondylolisthesis and
is more common in younger people. Slippage of L4 on L5 is most common
in degenerative spondylolisthesis and in older patients.
Half the patients are asymptomatic and condition is an incidental finding.
Sx: Lumbar pain aggravated by strenuous activity, particularly repetitive
flexion-extension or hyperextension.
Less than 30% slippage is managed conservatively.
Spondylolysis and spondylosis due to repeated hyperextension.
Incidence of spondylo in weightlifters (22 of 97 in one study) is
higher than in the general population.(4-7%). (Stone) Part of reason
press was removed as an Olympic lift.
Lower Back
During squatting, the back muscles act at a great mechanical
disadvantage because the horizontal distance from the weight to where the
lower back pivots (up to 18") is generally much greater than the distance
from the back muscles to the pivot point (about 2"). As with an ordinary
lever, the closer a force actis to the pivot point, the greater it must be
to exert a given torque. Therefore, the tensile force on the muscles and
tendons can be several times the weight of the bar lifted.
Any acceleration of the bar increases the force even further.
Both the force exerted by the weight on the shoulders (directly or
through the arms) and the force exerted by the lower back muscles act
to compress the spinal discs.
The flat back lifting posture has been found to be better overall
than a rounded back (ventral portion of the disc compressed) in
minimizing L5-S1 compressive forces and ligament strain. An arched
back (dorsal portion of the disc compressed) has been found to be
superior to a rounded back for avoiding injury.
The abdominal fluids and tissue kept under pressure by surrounding
muscle under tension has been described as a "fluid ball" which aids
in supporting the spinal column during lifting.
Harman, E. "Weight Training Safety: A Biomechanical Perspective"
Strength and Conditioning 16(5):55-60, 1994.
Mundt, D., et al. "An epidemiologic study of sports and weight lifting
as possible risk factors for herniated lumbar and cervical discs. The
Northeast Collaborative Group on Low Back Pain" American Journal of
Sports Medicine 21(6):854-860, 1993.
Osteoarthritis
Patellofemoral or tibiofemoral osteoarthritis in former competitive
weight lifters has been reported as 31% vs. 14% in competitive runners.
Patellofemoral arthritis was more prevalent (28%) in weight lifters than
in soccer players, runners and shooters. Cause was suboptimal technique
and below parallel squats.
OL and PL are no more susceptible to arthritic changes than general
population
Dx: Jointline tenderness and X-ray evidence of narrowed compartments,
tibial ridging and bony hypertrophy. Standing P-A in 30-45 of flexion.
Rx: Conservative
Kujala, U., et al. "Knee Osteoarthritis in former runners, soccer players,
weight lifters, and shooters" Arthritis Rheum 38(4):539-546, 1995.
Mazur, L., et al. "Weight-training injuries. Common injuries and preventative
methods" Sports Medicine 16(1):57-63, 1993.
Stress Fractures
Ulna, humerus, sternum and lumbar apophysis.
Focal or point tenderness (tuning fork)
Aseptic Necrosis
Avascular necrosis - most often in adolescents
Common sites: capitulum (Panners), lunate (Kienbocks), olecranon,
tibial tuberosity (Osgood-Schlatters) and calcaneus (Severs).
Mechanism of injury thought to be repetitive trauma or vascular changes.
Diagnosis based on age, lack of significant trauma, palpatory pain and
swelling and confirmation by diagnostic imaging. (Ames76)
Neuropathies
Chronic - take weeks or months to develop
Brachial Plexus at scalenes
Suprascapular nerve in posterior shoulder girdle by overhead lifting
Ulnar nerve at elbow by overtraining forearm
Radial nerve at forearm by overtraining forearm
Median and ulnar nerves at wrist by hyperextension
Peroneal nerve at fibular head (Ames 77)
Lateral Planter Nerve Entrapment
Johnson, E., et al. "Lateral Planter Nerve Entrapment:
Foot Pain in a Power Lifter" American Journal of Sports Medicine
20(5):619-620, 1992
Thoracic Outlet
Hypertrophy of the scalene and pectoralis minor muscles
Insidious upper-limb pain, ulnar hand paresthesias and thenar
weakness consistent with a lower trunk plexopathy. Physical exam,
EMG and vascular studies are often normal.
Suprascapular neuropathy (Suprascapular nerve in posterior shoulder
girdle by overhead lifting)
Suprascapular notch, under the transverse scapular ligament is
most common site for impingement of the suprascapular nerve.
Compression of the nerve affects both the supraspinatus and
infraspinatus muscles. The nerve can be traumatized by repetitive
shoulder abduction as in the military press.
Sx: Gradually increasing pain with or without weakness which
may not be noticeable until atrophy is present. The clinical
distinction between atrophy from suprascapular neuropathy and rotator
cuff injury can be difficult. Atrophy involving just the supraspinatus
muscle would be rare for suprascapular nerve problem. Isolated atrophy
of infraspinatus would be unusual with rotator cuff injury but could be
due to compression of infraspinatus branch of suprascapular nerve.
EMG can be helpful.
Scapular Winging
Caused by weakness of the serratus anterior muscle from a long
thoracic nerve injury or by weakness of the trapezius muscle from
an accessory nerve injury (Cranial nerve XI). No specific exercise
has been shown to predispose patients to scapular winging, but perhaps
the pads on the machines which rest on the shoulders (calf raises, leg
presses, hack squat) could contribute.
Sx: Winging from long thoracic nerve involvement is most prominent
at the infero-medial border of the scapula with shoulder flexion,
whereas accessory nerve palsies cuase superior medial winging.
Dx: Laboratory screen for infectious and inflammatory causes as well
as nerve conduction studies and EMG to establish level of injury.
Rx: Winging often resolves spontaneously within 3 - 24 months.
Musculocutaneous neuropathies
In a report of three patients, all occurred in the dominant arm
and spared the coracobrachialis muscle. The patients' symptoms
were precipitated by repetitive bicep curls.
Sx: Biceps muscle pain and weakness.
Theoretically, the symptoms are caused by impingement of the
musculocutaneous nerve from coracobrachialis muscle hypertrophy.
Notalgia paresthetica
Lesion of a thoracic dorsal primary ramus. It is not known if
this condition is seen in weightlifters and the injury mechanism is
unknown.
Sx: Chronic pain and sensory symptoms that are frequently described
as intense itching in an area 4 to 10cm in diameter over the thoracic
paraspinal muscles at the inferomedial scapula.
Rx: Capsaicin (depleting the local C fiber store of neuropeptides,
which are the principal substance responsible for transmitting pain
and itching.
Chronic Medical Conditions
Vascular stenosis
Uncommon, but may result from repetitive trauma to blood vessels.
External iliac artery stenosis in the region of the inguinal ligament
has been reported in cyclist. One report of a bodybuilder with
similar injury - hypothesis that repetitive hip flexion during leg press
and squat.
Sx: Anterior thigh pain
Weightlifter's cephalgia (Benign exertional headache)
Annals of Emer. Med. Vol. 11 No.8, 9/82
Pstgrd Med Vol. 71 No.3 3/82
Physician and Sports Medicine Vol.19 No. 8, 9/91
Physician and Sports Medicine Vol. No. , 5/97
1. Background- First described in 1932 on patients in whom severe pain
developed in head during maneuvers that incr. intrathoracic pressure
2. Described as brief in duration, sharply localized (diffuse PSM 99) and
comparable in intensity to a hammer blow (burning or boring pain).
Onset is sudden and the headache is localized to the posterior head and neck.
Headache may persist for days to weeks with gradual resolution.
Usually no neurologic signs or symptoms (Ames).
a. 60% . age 40, 75% men
3. Trigger mechanisms
No cause has been identified, the presumed mechanism is ligament or
soft-tissue injury (possibly cervicogenic -Ames).
a. Maneuvers which elevate intrathoracic pressure like coughing,
sneezing, laughing, defecating, stooping, shouting- Valsalva
b. Raise BP like leg press or any heavy weight lift, orgasm
c. Cause traction on intracranial content like jumping rope,
plyometrics
d. Shifting weather patterns- change in barometric pressure-
changes ion content of air- release of serotonin from platelets
e. Altitude
f. Hyperventilation- causes cerebral vasoconstriction with
subsequent vasodilatation
g. Muscular contraction
4. Mechanism of action:
a. Venous sinuses are among those structures within the head that
are pain sensitive- intrathoracic pressure incr. may cause temporary
obstruction of venous sinuses- i.e.. blood backs up causing distention of
venous structures causing pain.
b. Relative hypoglycemia makes one prone to exertional headache resembling migraine
c. Prostaglandin system alterations- physical activity causes
vasodilation
5. Prognosis- good if benign- may be self-limiting
6. Examination- Full neuro exam with CT or MRI to rule out neoplasm,
meningitis, subarachnoid hemorrhage, pheochromocytoma (esp. if there is
an incr.in BP), Arnold-Chiari malformation, platybasia, aneurysms, AV.
malformations
7. Initial management consists of stopping weight training, starting
cervical ROM and stretching and pain meds. Review lifting technique
and avoid valsalva (Ames).
Weightlifter's heart
Physiologic stress on the cardiovascular system during weight
training changes the myocardial architecture. The intraventricular
septum thickens relative to the ventricular free wall. May be
inaccurately diagnosed as gyprtrophic obstructive cardiomyopathy,
however, the ratios of intraventricular septum thickness to body
surface area and of ventricular free wall thickness to body surface
area are the same in weight trainers and controls. In HOCM these
ratios are significantly greater than in controls.
Hernias
No incidence or prevalence studies have been completed.
CHILDREN
Prevention of Injuries
Only a few studies have demonstrated a decreased injury rate in
adolescents who have undergone resistance training. A pre-season
conditioning program that included resistance training led to a decrease
in the number and severity of injuries in high school football players.
Resistance training decreased the incidence of shoulder problem in teenage
swimmers and older athletes.
In one report involving high school male and female athletes,
injuy rate for those who performed resistance training was 26.2% (
2.02 days rehab) compared to 72.4% (4.82 days rehab) for those who did not.
Guidelines
1. Child should be psychologically and physiologically ready
2. Have realistic expectations
3. Safe exercise environment and equipment
4. 5-10 minutes warm-up and specific warm-up
5. Close supervision and proper instruction in technique,
spotting and etiquette (returning weights to trees)
6. Light loads (12-15 RM)
7. Gradual increase in resistance - 5-10% in overall load
8. Gradual progression in sets, exercises and training sessions
(periodization)
9. Child should feel comfortable
10. Advanced exercises may be shown with proper instruction
11. Competition should be discouraged, fun is focus
12. Drink plenty of fluids
13. Encourage participation in variety of sports and activities
14. Instructors and parents should be good role models
Faigenbaum, A, et al. "Youth Resistance Training: Position Statement
Paper and Literature Review" Strength and Conditioning 18(6):62-75, 1996.
Faigenbaum, A, et al. "Olympic-Style Weightlifting, Kid Style" Strength
and Conditioning Journal 21(3):73-76, 1999.
WOMEN
Physician and Sports Medicine 16(4),1988.
NSCA 8&10/89
Ebben, W. and Jensen, R. "Strength Training for Women"
Physician and Sports Medicine 26(5):86-97,1998.
A. History
1. Female participation in resistance exercise began in the
1950's with a few track an field athletes. Previous henerations
were inhibited by social stigmas and lack of physiological research.
2. Passage of Title IX in 1972 provided impetus for subsequent growth
of RE for female athletes
3. First weightlifting world championships in 1987
World Records: Clean and Jerk 315, Snatch 249
4. First powerlifting world championships in Mass.in 1980
1980 - 97,105,114,123,132,148,165,181,shwt
Squat: 507
Bench: 264
DL: 452
Total: 1157
1999 - Added 198, then shwt
Squat: 615
Bench: 393
DL:584
Total: 1494
B. Socio-psychological considerations
1. Cultural stigmas- femininity, appearance, appropriateness
2. Western society belief systems- men v. women with regard to
physical expression and body image.
C. Physiological considerations
1. Strength
*MSSE 6/95, 906- Increased strength in older females
a. Absolute body strength of females is about 2/3's of males, although
this difference is not consistent for all muscle groups.
- Absolute lower body strength ranges from
60-80% of males
- Absolute upper body strength ranges
from 35-79% of males
- More data needed
b. Men may have advantage in neuromuscular response times that
results in greater force production speed than women (PSM 99)
c. Distribution of fiber types (fast and slow twitch) is similar in
two sexes
d. Women able to use a greater portion of stored elastic energy that men
during activities in which muscle is pre-stretched, such as counter-
movement prior to jumping.
e. Based on strength to lean body mass ratio, women are about equal to men
f. When strength calculated per cross-sectional area of muscle, no
significant difference exists.
g. Measuring strength this way suggests that muscle at the
cellular level has a force development capability independent of
sex and that women benefit from strength training at least as much as
men. (PSM 99)
2. Body size and lean body mass taken into consideration,
relative strength differences are appreciably less.
- Lower body- almost equal to males
- No difference in force per unit of cross sectional muscle
c. At maturity, males are 13cm taller, 14-18kg heavier, 18-22kg more
lean body mass, 3-6kg less fat weight (avg. body fat of
15 compared to 23%)
3. Body composition
a. RE will decr. body fat, incr. lean weight, and either
no change or slight incr. in total weight
b. Remember gender characteristic fat stored around mamary glands
and pelvic/thigh region
4. Hypertrophy
a. Muscle will hypertrophy due to RE
b. Relative degree is equal to males but absolute is smaller
c. Genetic predispostion to hypertrophy and/or exogenous androgen use
most likely play significant roles in determining amount of hypertrophy
achieved.
d. Females have similar fiber type distribution but fibers are
smaller in cross-sectional area
e. Functional quality of muscle is the same in regard to
contractile properties and the ability to develop muscle
strength
5. Androgens
a. Produced by adrenal glands and the ovaries- contribute about
equally exept at mid-cycle
b. Females have 1/10th the testosterone- this account for some
of the above differences in strength and hypertrophy. Levels do vary.
c. No exercised induced incr. in testosterone NSCA V14No2
d. Androstenedione: absolute response to weight training is similar
in males and females (PSM 99)
6. Menstrual cycle- how menstrual cycle affects hormonal responses
to RE remains unclear
a. Masterson, Gerald. "The Impact of Menstrual Phases on
Anaerobic Power Performance in Collegiate Women" Journal of
Strength and Conditioning Research, 13(4): 325-329, 1999.
The women in this study demonstrated greater anaerobic
capacity, produced greater peak power and were less
fatigued by the end of the exercise during the luteal phase
than during the follicular phase.
Follicular phase: within 48 hours of the first
noticeable sign of menstruation
Luteal phase: End of flow within 14-15 days.
b. Little evidence to suggest onset affects athlete performance
c. Menstrual cycle does alter certain hormone concentrations and response
to exercise
- early follicular phase, higher growth hormone concentration
d. Tremendous variation in responses to menses
7. Pregnancy
a. Little data- anecdoctal evidence suggests that women may
safely train during prenancy using a little common sense
b. Reduced levels of testosterone
8. Bone structure
a. Narrow shoulder of women causing problems- no evidence to
support this
b. Must pay attention to carrying angle at elbow, Q angle at
knee
D. Injuries
1. Women may be more predisposed due to wider hips and smaller shoulders
2. Greater Q angle at knee- more of theoretical argument
3. Excess joint laxity may predispose to dislocations
4. Smaller wrists
5. Back problems are common in female track and field athletes
6. Advantage- incr. flexibility
E. Studies
AR&FA v12n2 2/94 p.2
1. Collegiate women's tennis players on 30min to 1 hour RE 2-3
times per week for 9 months to players who did only regular conditioning.
2. Routine: bench presss, seated shoulder press, upright rows, seated rows,
lat and front raises, lat pulldowns, wrist curls, sit-ups, split squats,
leg press, calf raise, back extensions and arm curls.
a. avg. serve incr. from 60mph to 77 mph, control had no change
b. Backhand stroke up 35% and forehand 19%, no change control
c. Grip strength up, no change control
d. Short burst of power incr. signif., no change control
e. Body fat from 24% to 19% with incr. in LBM, no change control.
F. Osteoporosis
LaFontaine, T. "Resistance Training and Bone Health" Strength
and Conditioning Journal 21(1)11-12.
1. Osteoporosis: 2 types
a. Type 1 presumed to be due to estrogen deficiency in women
b. Type 2 result of calcium and vitamin D deficiency
c. 4/10 women, 1/10 men develop OP after 65
d. 1.5 million OP related fractures per year - hip, spine and wrist
e. Risk factors: female gender, advance age, Caucasian/Asian, family history,
low body weight, premature menopause, prolonged dysmenorrhea, not having
born children, low dietary calcium and excessive alcohol intake.
f. Bone mass peaks in 2nd and 3rd decades in women. Thereafter,
0.5% to 1.0% loss annually till menopause. After menopause, bone
loss is accelerated because of a secondary deficiency of estrogen.
This loss is accelerated by a low calcium inatke and lack of weight-
bearing exercises.
g. NASA- astronauts who were measured for bone density 5 or
more years after returning from space continued to show reduced bone mass.
h. Swimmers have lower BMD than athletes who weight bear.
i. Longitudinal studies of exercise and OP in pre-menopausal women are
equivocal. However, many of earlier studies failed to adequately apply
key principles of training such as specificity, overload, progressive
resistance, etc.
j. Recent study of 40 post-menopausal estrogen-deplete women,
ages 50-70 assigned to high intensity program consisting of knee
and hip extension, lateral pull-down, back extension and abdominal
flexion at 84% of 1RM, 3x8 every other day for 1 year and compared
to sedentary control. DEXA scan showed hip and spinal BMD increased
significantly and decreased in control.
2. Recommendations
a. Physician's clearance
b. Initial DEXA
c. >75% 1RM, 6-10 reps, 3 sets and progressive increase in load
of free weight lifting.
d. Calcium 1000mg to 1500mg (Magnesium), Vitamin D 400IU to 800IU
e. Protein: at least .6g protein/lb. bodyweight.
AGING
I. Intro: image of strength for elderly incongruous but may help decrease
injury and improve quality of life
1. Emphasis on strength
a. Studies show assoc. between lower extremity muscle
weakness and risk of falling- big problem as about 40% of
people over 65 fall at least once per year.
b. Muscle strength declines even in trained athletes after
age 60-65 for unknown reasons
c. Many clinical problems relate more to muscle weakness
than lack of aerobic fitness
- Old people probably not destined genetically
to die of heart disease; what they die of is
osteoporosis, i.e., hip fracture and immobility
- Inability to get out of chair, not inability to
run across street is limiting their quality of
life
d. e.g., 89 year old may require more than 100% strength in
quads, rising occurs in .6 seconds
e. Arm strength fairly well preserved because they use
their arm muscles even if sedentary
f. Developing leg strength more critical because it
tends to decrease more rapidly
Adams, K., et al. "Aging: It's Effects on Strength, Power, Flexibility
and Bone Density" Strength and Conditioning Journal 21(2):65-77, 1999.
A. Strength - Resistance training essential for those 50 and over
1. Aging human body is highly resilient in its capacity to cope and
adapt to high-intensity resistance training as seen in two case
studies of powerlifting
a. Subjects subjected themselves to a level of training intensity
normally associated with younger athletes with no negative
effects.
2. Common weakness in studies was lack of sufficient training intensity,
volume and frequency.
B. Muscle Power
1. Age related decline can be slowed and even reversed.
However, neither machine nor free weight training is effective
incontrolling this decline. Freestanding power-type lifts that
train and develop the body as a functional unit through a full range
of multi joint body movement, i.e., power snatch and power clean.
2. Bemben, Michael and McCalip, Gregory. "Strength and Power
Relationships as a Function of Age" Journal of Strength and
Conditioning Research, 13(4): 330-338, 1999.
The ages of 50-65 years represents a critical period when factors
other than the amount of fat-free tissue are responsible for the
beginning decline in neuromuscular strength and power.
Strength con be maintained from age 20 to 50.
· Possible factors: Fiber type shift - loss of type II
motor units and fibers become smaller as subjects age
· Increase in fiber density in the type I motor units begins at
about age 60
· Fiber number may max out at 25 and decrease by 40% by age 80
C. Flexibility
1. Declines 20-30% between ages 30 and 70.
2. Free weight training must be combined with flexibility training.
D. Bone Density
1. High intensity free weight training utilizing squats and dead
lifts is necessary to significantly increase bone density. Machine
training seems to have no effect on increasing bone density.
2. Free weight training may help people with arthritis. Bone strength
is accociated with good muscle, ligament and tendon strength.
Together they reduce stress placed on the joint surface. Physical
inactivity causes significant loss in ligament and tendon strength and
hence joint strength.
E. Free Weight v. Machines
1. Research data overwhelmingly support use of free weights in
developing overall strength, power and flexibility. It develops
superior neuromuscular function and coordination, especially in the
muscle sensory system. This translates into improvement or maintenance
of motor skills critical to independent living.
PSM 11/89 v17n11
Etta Clark-Growing Old is not for Sissies
20/20 Tape
*MSSE 4/94, 432- Skeletal myo weakness in old age
*MSSE 6/95, 941
B. Benefits
1. Incr. strength
2. Improve walking speed
3. Improve ability to get up and down and climb stairs
C. Risks
1. Valsalva
2. No training with uncontrolled angina or recent myocaridal infarction
D. Program description
1. Machines- low cost, balance, form, weight stacks, incr. in small
increments
2. Prescription
a. Use all muscle groups, 2-3 times per week, 20-30 min/session
b. Light weight
c. Warm up and cool down
d. Make sure someone is around
STRENGTH TRAINING FOR THE PHYSICALLY CHALLENGED
*NSCA 2/94, 66
Injury Prevention By Use Of Weight Training
One study showed a decreased injury rate of athletes who performed a
RE program compared to those who did not. Studies have shown decreased
time lost from sports and faster rehabilitation time. National Strength
and Conditioning Association Journal 2/82 Study- weight trained had
1/3 the injuries of non-weight trained and weight trained had 1/2 the
time lost.
*Barrier Trigger Points National Strength and Conditioning Association
Journal 12/93, 39
Prevention of Injuries
1. Proper preparation: One or more warm-up sets
2. Examination of athlete
3. Strength balance
4. Flexibility
5. Proper technique- avoid Valsalva
a. Basic exercises should be performed through a full range of motion.
6. Proper manipulation of training variables
7. Proper equipment maintenance
Parts lubricated, floors cleaned and disinfected, plates put away
properly, proper spacing between equipment, non-slip flooring,
properly padded equipment.
Armitage-Johnson, S. "Safe Training Environment, Part III, Maintaining
Equipment" Strength and Conditioning 16(3):54-55, 1994
Polson, Gary. "Weight Room Safety Strategic Planning-Part III"
Strength and Conditioning 16(6):62-64, 1994.
Strength and Conditioning 2/94, :64, 1994.
Proper teaching guidelines
o Introduce the exercise and describe the body area that is affected.
o Explain and demonstrate the proper body position and hand grip.
o Explain and demonstrate the lifting technique.
o Demonstrate common errors and how to correct them.
o Demonstrate and explain proper spotting and safety techniques.
o Monitor students as they lift and spot. (Bowers)
o When a new exercise is introduced or athlete has greater than two
week layoff, light weights should be used.
o Do not work through pain
o Maximal lifts should not be performed without proper preparation.
(Harman)
Bowers, C. "Guidelines for Teaching Free-Weight Exercises"Strength and
Conditioning 18(1):63-64, 1996.
Harman, E. "Weight Training Safety: A Biomechanical Perspective"
Strength and Conditioning 16(5):55-60, 1994.
Common Weight Training Errors- know your functional anatomy
1. Behind the neck pull downs
2. Behind the neck shoulder press
3. Picking up weights from the rack
4. Moving head while doing any lift
5. Unequal loading of the bar
5. Wrist position and hand placement on bar during pressing movements
6. Lateral Raise- Wrist flexion
8. Squatting- forward lean
9. Squatting- use of board
10. Squatting/Leg Press- Knee wiggle and foot placement
11. Squatting- Butt back first, not down
12. Squatting- knees over toes
13. Squatting- bar placement on the back
14. Bench Press- feet on the ground
15. Bench Press- scapular retraction
16. Bench Press- even grip on the bar
17. Dead Lift- Lifting buttock
18. Sit up- Knees bent, unsupported; hand position
19. Shrug- protracted chin causing cervical flexion
ABDOMINAL EXERCISE DEVICES
Whitting, W, Rugg, S., Coleman, A., Vincent, W. "Muscle
Activity During Sit-ups using Abdominal Exercise Devices"
Journal of Strength and Conditioning Research, 13(4): 339-345, 1999.
Abdominal devices (AB Roller Plus, AbSculptor, Ab Trainer, AbWorks)
do not elicit any greater or lesser involvement of the abdominal
musculature than does performing similar exercises unassisted.
No benefit or detriment with devices.
Lower SCM activity in all devices compared to crunch.
EFFECTS OF WEIGHT BELT ON INTRA-ABDOMINAL PRESSURE
1 Bauer, Jeffrey, Fry, Andrew, Carter, Cory. "The Use of
Lumbar-Supporting Weight Belts While Performing Squats: Erector
Spinae Electromyographic Activity" Journal of Strength and
Conditioning Research 13(4): 384-388, 1999.
2 Faigenbaum, A. and Liatsos, N. "The Use and Abuse of Weightlifting
Belts" Strength and Conditioning 16(4):60-62, 1994.
3 Harman, E., et al. "Effects of a belt on intra-abdominal pressure
during weight lifting" Medicine and Science in Sports and Exercise
21(2):186-190, 1989.
4 Lander, J., et al. "The effectiveness of weight-belts during the
squat exercise" Medicine and Science in Sports and Exercise
22(1):117-126, 1990.
5 Lander, J., et al. "The effectiveness of weight-belts during
multiple repetitions of the squat exercise" Medicine and Science in
Sports and Exercise 24(5):603-609, 1992.
6 Strength Power Update Summer, 1986
Bauer: Mean erector spinae activity was greater in the lumbar
region of the spine when wearing weight belts during squatting exercises
than the mean activity in subjects who were not wearing weight lifting
belts.
Results were contrary to what was expected, since it is believed that
the use of weight belts provides additional support to the spine and
therefore should result in a decrease in the activity of the musculature
used to stabilize the spine during lifting tasks.
Tightening of belt may pre-load erector spinae before any flexion of the
spine or contraction of the erectors occurs.
Use: Device for reducing stress during overhead lifts in which
force was directed toward hyperextension of the trunk, i.e..
overhead press and jerk. The general purpose is to provide
support for the lower back.(1)
Inter: Both PL and WL use lifting belts to aid in the stability
of the trunk during heavy lifts.
A. Types of belts
1. 6" in back, 2" in front
2. 4" in back, 2" in front
3. 4" all the way around.
4. Power belt: 4" all the way around, legal belt in PL contests, is not more
than11cm wide and 13mm thick. These belts are multi-layered and provide a
bit more support.
B. The ligaments supporting the spine can only withstand 4-5lb. of force
before they will topple. In contrast, total body lifts require a stable
spine that can withstand literally tons of force.
C. IAP
1. A piece of leather pressed against the spine will not in and of itself
support the back regardless of whether it is 6" or 4" wide.
2. True function is to increase the pressure in the abdominal cavity by
wearing it as tight as possible and by pushing against the front part of
the belt. Belt prevents protrusion of ab. myo
3. By doing this one can increase the IAP so that it supports the load.
4. Most lifters close their glottis while attempting to forcefully expire
(valsalva). This incr. the ITP and inflates and stabilizes chest cavity
5. Both maneuvers serve to take load off discs and back myo
6. Healthy vert. can withstand 5000-8000N (1100-1800lb) of compressive force.
This varies with age and physical condition
7. In a study examining lifting bars, Lander found compressive forces on
spine up to 1910lb.; shear forces up to 675lb. and back myo forces up to
1800lb.
8. Without taking into account IAP, back myo would have to generate 44%
more force (2600lb) and the compression on the spine would increase 64%
to 3150lb. Clearly, IAP has a profound effect on the forces acting on the
structures on the spine. IAP decr. these compressive forces by up to 40%.
9. It has been hypothesized that IAP during a lift may result in the
formulation of a rigid tube-like structure that limits spinal flexion,
thereby decreasing the forces placed upon the supporting structures of the
lower back.(2)
10. A belt will increase IAP by compressing(2) or preventing the protrusion(3)
of the abdominal compartment. IAP reduces forces required of the lower
back muscles to perform a lift. Because the spinal erector forces tend
to compress the spinal discs, the reduction of such forces has been said
to reduce the likelihood of compressive injury to the spinal discs.(2)
E. Blood Pressure and Heart Rate
1. Blood pressure and heart rate my be elevated while wearing a
tightly cinched belt. Individuals with a comprised cardiovascular
system would appear to be at greater risk when undertaking exercises
with a back support.(1)
F. Recommendations
1. Use a 4" all the way around belt; the stiffer the better.
Typically, 4-7mm thick. In powerlifting the dimensions are no
more than 13cm wide and no more than 11mm thick. If 4" in front
uncomfortable, esp. at bottom of squat, get one that is narrow in front.
2. Just prior to set, tighten belt as much as possible
3. Take a trunk stabilizing breath and close glottis to increase ITP
4. Tighten ab. myo and push or squeeze against the belt to increase IAP
(valsalva)
5. Lower the weight, making sure to maintain a stable and tight feeling
trunk at the bottom of the lift.
6. Raise the weight and begin to exhale after the "sticking" point.
7. At completion of lift complete exhalation and prepare for next rep.
8. NOTE: all lifting does not need a belt. Electromyographic activity of the rectus abdominus, external oblique and erector spinae were reduced when a belt was worn.
a. Abdominal muscle will not be fully strengthened
b. Difference in neuromuscular control of IAP generating myo
c. General rule: wear belt on near maximal or maximal attempts-
loads above 80% 1RM. Interestingly, Lander noted that
weightlifting belts may actually be more important when
performing multiple repetitions with a submaximal load. During
the last few repetitions of a set, muscular fatigue may make it
difficult to execute given exercise properly, adding additional
strain the lower spine.(4)
d. Use only on exercises during which the spinal erectors work
against high resistance (squat, dead lift) or in which the
spine may hyperextend
(military press).(1)
MUSCLE SORENESS
Clinics in Sports Medicine
Medicine and Science in Sports and Exercise 24(5):510-542, 1992.
Mechanical cause of injury- related to duration and intensity of exercise.
Teague, B. and Schwane, J. "Effect of intermittent eccentric contractions
on symptoms of muscle microinjury" Medicine and Science in Sports and
Exercise 27(10):1378-1384, 1995.
Ross, M. "Delayed-Onset Muscle Sorness" Physician and Sports Medicine
27(1):107-108,1999.
3 Types: DOMS, Acute, Injury
A. DOMS
1. Characterized by:
- Diffuse muscle tenderness occurring 12-48 hours after exercise and persists 4-12 days and disappears
- Tenderness to palpation
- Increased muscle stiffness
- Decreased ROM
- Occurs in beginner athlete or experienced athlete returning
after long layoff; sharp increase in load may bring DOMS on
2. Causes
- Microtrauma- tiny tears in myo fibers and adjacent connective tissue
- Waste products formed by biochemical process in muscle as a result of muscle contraction
- Eccentric exercise- due to increased stretch and strain of muscle.
-eccentrics cause increased number of Motor Unit to fire
- Tonic spasms in local Motor Unit: disruption of calcium handling
of SR in fibers used during exercise results in increase
in calcium and fiber degradation
3. Bottom line- mechanical damage to myo
4. Recommendations
- Beginner athlete should use light loads
- Avoid large load increase or drastic increase in reps or load duration - Proper warm-up
- Stretching
- Proper use of clothing
- Ice after workout
C. Acute
1.Characterized by:
- Soreness appearing during exercise, after contraction, that can last up to 48 hours after exercise
- Appears during isometric contractions
2. Cause
- Related to contraction related ischemia
- Pain is decreased once circulation is restored
3. Recommendations
- Be careful with isometrics
- Use less than max attempt for less than 1 minute
D. Injury
Medicine and Science in Sports and Exercise 9/95, p.1263
1. Related pain during rapid, repetitive exercise at high speeds or an accident
- Incr. inertia allows for possibility of tendon and ligament stretching and tearing and joint subluxation
2. Recommendations
- Rate of less than 1 rep per second may be dangerous
- Realistically, ballistic movements are difficult to avoid
- Be careful with plyometrics
3. Eccentric action: greater myo damage, peak soreness 2-3
days post, peak swell 5 days post
- Restoration next 10 days
- CK blood levels do not incr. precipitate until 2 days post
cytoskeletal and myofibrillar damage
OVERTRAINING
Susceptibility varies greatly with individuals. Intensity, overall health status, quantity of training and duration of training contribute to overtraining more than the specific type of training performed. National Strength and Conditioning Association Journal 8/92
1. Emotional warning signs
a. Incr. nervousness or depression
b. Inability to relax
c. Lack of desire, mental attitude of "I don't care."
d. Drop in academic or job performance
2. Physiological warning signs
a. Extreme soreness and stiffness after training
b. Gradual incr. in soreness from session to session
c. Decr. body weight when no effort made to lose weight
d. Inability to complete training session that should be able to be completed
e. Sudden incr. in resting heart rate when taken at same time each day
f. Lowered resistance- colds, headaches, flu
g. Loss of appetite
h. Swelling of lymph nodes
i. Constipation or diarrhea
j. Unexplained drop in athletic performance
k. Decr. sex drive
3. Recommendations
a. Do not incr. intensity, frequency, duration suddenly
b. Allow proper recover time
c. Get enough sleep
d. Eat balanced diet- carbohydrates!
e. Individualize training intensity
f. Monitor heart rate- if incr. 5 beats per minute, rest
g. Know each athlete individually as signs of overtraining are subjective
- susceptibility varies greatly with individuals; intensity, quantity of training, duration of training contribute to overtraining more than the specific type of training performed.
h. Know overall health status of athlete
i. Training to failure is not necessary. Use a periodized approach. (Stone)
Stone, M., et al. "Training to Muscular Failure: Is It Necessary?"
Strength and Conditioning 18(3):44-48, 1996.
CONTRIBUTION OF REST TO MUSCULAR DEVELOPMENT
Journal of Applied Sports Science Research, Vol. 5 No.4, p. 219
Three Types Of Rest
1. Intratraining: between sets.
2. Intertraining: between sessions
3. Pre-performance
A. Intratraining Rest
1. Energy systems
a. ATP-PC- energy for all myo contraction comes from P being cleaved from ATP. May be nearly depleted in 15 sec. 5 or fewer reps in 12-15 sec. to failure is this system
b. Anaerobic glycolysis: > 5 reps and < 3min. betw. sets
c. For maximum strength- need 3-5 min. rest betw. sets
B. Intertraining Rest
1. After a workout need rest for myo to fully recover from
stress placed on them. What is lacking is either a physiologic
marker or definitive time frame indicating when lifter should repeat
session for optimal results. Many coaches use volume as a guide.
Look for overtraining signs.
C. Pre-Performance Rest
1. No evidence strength is lost after 5 days rest
2. Ideal time may be about 4 days rest
3. Powerlifting example.
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