Transcript Chapter 4: Preventing Injuries Through Fitness Training

Chapter 4: Preventing
Injuries Through
Fitness Training
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• Fitness is critical for performance and
injury prevention
• Improper conditioning is a major cause
in sports related injuries
• Areas of concern:
– Flexibility
– Muscular strength, endurance, power
– Cardiorespiratory endurance
• Coaches need to develop program that
focuses on injury prevention and
performance enhancement
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Periodization in Training
and Conditioning
• Traditional seasons no longer exist for
serious athletes
• Periodization
– Achieve peak performance
– Decrease injuries and overtraining
– Program that spans various seasons
– Modify program relative to athlete’s needs
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Year Round Training Cycle
• Complete training cycle
• Seasonal approach based on
preseason, in-season, and off-season
• Changes in intensity, volume, specificity
of training occur in order to achieve
peak levels of fitness for competition
• Broken into periods or phases (lasting
weeks or months)
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Periods or Phases
• Transition period:
– Follows last competition (early off-season)
– Unstructured (escape rigors of training)
• Preparatory period:
– Off-season
– Hypertropy/endurance phase (Low
intensity with high volume)
• Allows for development of endurance base
• Lasts several weeks to 2 months
– Strength Phase
– Power Phase (High intensity/ pre-season)
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• Preparatory period (continued)
– Strength Phase
• Intensity and volume increase to moderate levels
– Power Phase (High intensity/ pre-season)
• Volume is decreased to allow adequate recovery
• Competition period:
– May last a < week or several months for
seasonal sports
– High intensity, low volume, skill training
sessions
– May incorporate weekly training cycles (1-7
days)
• Designed to ensure peak on days of competition
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Cross Training
• Training for a sport with substitutions of
alternative activities (carryover value)
• Useful in transition and preparatory
periods
• Variety to training regimen
• Should be discontinued prior to
preseason as it is not sport-specific
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Foundations of
Conditioning and Training
• Warm-up/Cool-down
• Motivation
• Overload and SAID
principle
• Intensity
• Specificity
• Individuality
• Consistency/routine
• Relaxation/Minimize
Stress
• Progression
• Safety
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Warm-up
• Precaution against unnecessary
musculoskeletal injury and soreness
• May enhance certain aspects of
performance
• Prepares body physiologically for physical
work
• Stimulates cardiorespiratory system,
enhancing circulation and blood flow to
muscles
• Increases metabolic processes, core
temperature, and muscle elasticity
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General
– Activities which bring a general warming to
the body(break a sweat)
– Not related to sport
Specific
– Specific to sport
– Stretching, jogging, running, throwing,
catching
Should last 10-15 minutes resulting in
effects that will last 45 minutes
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Cool-down
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•
•
•
•
Essential component of workout
Bring body back to resting state
5-10 minutes in duration
Often ignored
Decreased muscle soreness following
training if time used to stretch after
workout
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Why is it important to have
good flexibility?
• Flexibility
– Ability to move a joint(s) smoothly through
a full range of motion (ROM)
• Originally believed that decreased ROM
results in:
– Decreased performance capabilities
– Uncoordinated/awkward movements
– Predisposes athlete to injury
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• New evidence indicates that it may be more
important for participation in more dynamic
activities
– Activities that require jumping, bounding
– High intensity stretch-shortening cycles (where
muscle tendon unit requires storage of more
elastic energy
– Without necessary flexibility the tendon may
exceed capacity
– Stretching can influence viscosity of tendons
making it more compliant = injury reduction
• No scientifically based evidence to support
relationship between stretching and
occurrence of injury
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Factors That Limit Flexibility
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Bony structures
Tissue approximation
Excessive fat
Muscle and tendon lengths
Connective tissue
Scarring and contractures
Skin
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Range of Motion
(ROM)
Active range of motion = dynamic flexibility
– Ability to move a joint with little resistance
• Passive range of motion = static flexibility
– Motion of joint to end points without muscle
contraction
• Must be able to move through unrestricted
range
• Must have elasticity for additional stretch
encountered during activity
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Agonist vs. Antagonist
Muscles
• Joints are capable of multiple movements
• Example:
– Quadriceps will extend knee with contraction
– Hamstrings will stretch during extension
– Quads (muscle producing movement)
referred to as agonist
– Muscle undergoing stretch referred to as
antagonist
– Agonist and antagonist work together to
produce smooth coordinated movements
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Stretching Techniques
Ballistic
– Bouncing movement in which repetitive
contractions of agonist work to stretch
antagonist muscle
– While effective in improving flexibility,
caution should be exercised
• Increased motion is achieved through a series
of jerks on resistant tissue
– Possible soreness may result if jerks are
greater than tissue extensibility
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Dynamic
– Stretching technique of choice in athletic
populations
– Related to types of activity an athlete will
engage in
– Tend to be more functional in nature
– Recommended prior to beginning an
activity
– Stretches that mimic components of
athletic activity
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Static stretching
– Passively stretching
– 20-30 second hold = optimal
– Go to point of pain and back off and hold
for 30 seconds (3 to 4 times)
– Controlled, less chance of injury
– Not dynamic
– Should precede ballistic stretching
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Proprioceptive Neuromuscular Facilitation
– Physical therapy for neuromuscular
paralysis
– Slow-reversal-hold-relax
– Contract-relax
– Hold-relax
• Ten second push, ten second relax
– Best technique to improve flexibility
– Technique that involves combination of
alternating contractions and relaxation of
both agonist and antagonists
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Stretching Exercises
Shoulder Towel Stretch Exercise
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Anterior Abdominal Stretch
William’s Flexion Exercises
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© 2010 McGraw-Hill Higher Education. All rights reserved.
Assessment of Flexibility
• Various devices have been designed to
accommodate joint sizes and
complexities of movement
• Goniometer most widely used device
• Can also utilize the following tests:
– Trunk hip flexion test
– Trunk extension test
– Shoulder extension test
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Flexibility Assessments
Trunk & Hip Flexion Test
Trunk Extension Test
Shoulder Lift Test
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Is there a relationship
between strength and
flexibility?
• Co-exist
• Muscle bound = zero flexibility
• Strength training will provide individual
with ability to develop dynamic flexibility
through full range of motion
• Develop more powerful and coordinated
movements
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Muscular Strength,
Endurance, and
Power
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Muscle Strength, Power,
and Endurance
Strength: ability to generate force against
resistance
Muscular endurance: repetitive muscular
contractions (increase strength =
increase endurance
Power: is the relationship between
strength and time
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Types of Skeletal Muscle
Contractions
• Isometric contraction
– No length change occurs during contraction
• Isotonic contraction
– Concentric- shortening of muscle with
contraction in an effort to overcome more
resistance
– Eccentric - lengthening of muscle with
contraction because load is greater than
force being produced
– Both are considered dynamic movements
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Factors that Determine
Levels of Muscular Strength
• Size of muscle:
– Function of diameter and of muscle fibers
– Hypertrophy vs. Atrophy
• Number of muscle fibers
• Neuromuscular efficiency
– Initial gains are due to increased efficiency
• More effectively engage specific motor units
• Biomechanical factors
– Bones and muscles = Levers and pulleys
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• Fast-Twitch vs. Slow-Twitch Muscle Fibers
– Motor units with distinct metabolic and
contractile capability
Individual make-up
– Muscles contain both types of fibers
– Muscle functioning impacts ratios (postural vs.
powerful movement)
– Genetically determined
• Slow twitch (Type I):
– Generally major constituent of postural muscles
• Fast twitch (Type II)
– High force in short amount of time
– Produce powerful movements
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• Levels of Physical Activity
– Will influence increase/decrease in muscle
strength
– Also impacts cardiorespiratory fitness,
flexibility and increases in body fat
• Overtraining
– Psychological and physiological
breakdown
– Signs
• Apathy, loss of appetite, staleness, declines in
performance, weight loss, inability to sleep
– Prevent through appropriate training
protocol, proper diet and rest
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What physiological changes
occur to cause increased
strength?
• Multiple theories of muscle hypertrophy
• Primary explanation of muscle
hypertrophy:
– Increase in protein myofilament number
and size
• Continued need for additional research
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Core Stabilization Training
• Core refers to the lumbo-pelvic-hip
complex
– 29 muscles in the lumbar spine, hip,
abdomen and around the hip and pelvis
• Will help to improve:
– Postural control and muscular balance
– Allow for expression of dynamic functional
strength and dynamic stabilization of
kinetic chain
– Improve neuromuscular efficiency
throughout the body
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• Often a focus on functional strength,
neuromuscular control and power
relative to activity
– Core training spinal stabilization is often
neglected
• Optimal stabilization of the spine allows
for effective utilization of strength,
power and control of the prime movers
– If core is weak, movement efficiency
declines
– Could lead to injury
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• Core training is designed to help
develop strength, neuromuscular
control, power and endurance within the
lumbo-pelvic complex
– Exercises must elicit maximal training
response
– Should be safe, challenging, stress
multiple planes, and incorporate a variety
of resistance equipment
– Begin with activities where you are able to
maintain stability and optimal
neuromuscular control
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© 2010 McGraw-Hill Higher Education. All rights reserved.
Techniques of Resistance
Training
• Progressive resistance exercise
• Overload principle must be applied
• Must work muscle at increasingly higher
intensities to enhance strength over
time
• If intensity of training does not increase,
but training continues, muscle strength
will be sustained
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Isometric Exercise
• Contraction where muscle length
remains unchanged
• Muscle contraction that lasts 10
seconds and should be performed 5-10
times/daily
• Pro: quick, effective, cheap, good for
rehab
• Con: only works at one point in ROM,
produces spiking of blood pressure due
to Valsalva maneuver
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Progressive Resistance
Exercises (Isotonic training)
• Shortening/lengthening contractions
against fixed resistance
• Concentric vs. Eccentric
• Various types of equipment can be
utilized
– (Free weights, machine weight)
• Spotter is necessary for free weight
training to prevent injury, motivate
partner and instruct on technique
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• Concentric and eccentric training should
be incorporated for greatest strength
improvement
• Concentric phase of lift should last 1-2
seconds, eccentric phase 2-4 seconds
• Variations exist between free and
machine weight lifting
– Motion restrictions, levels of muscular
control required, amount of weight that can
be lifted
– Equipment design, varying resistances
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Progressive Resistance
Exercise Techniques
• Terminology associated with weight
training
– Repetitions
– Repetition maximum
– One repetition maximum
– Set
– Intensity
– Recovery period
– Frequency
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• When training should be able to perform
3 sets of 6-8 repetitions
• Increases should occur in increments of
10%
• 1 RM can be utilized to measure
maximum amount of weight that can be
lifted - must be very careful
• Training of a particular muscle group
should occur 3-4 times per week (not on
successive days)
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Muscular Endurance vs.
Strength
• Training for endurance enhances
strength and vice versa
• Training for strength should involve
lower repetitions at heavier weight
• Training for endurance requires lower
weight at 12-15 repetitions
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Strengthening Exercises
Bench Press
Shoulder Rotation
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Leg Exercises
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Open vs. Closed Kinetic
Chain Exercises
• Anatomical functional relationship for
upper and lower extremities
• OKC
– When foot or hand are not in contact with
the ground or supporting surface
• CKC
– Foot or hand are weight bearing
– Widely used = more functional
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Isokinetic Training
• Muscle contraction at a constant
velocity
• Maximal and constant resistance
throughout the full range of motion
• Maximal effort = Maximal strength gains
• Rehab
• Never widely used in strength training
• Losing popularity in rehabilitation
settings
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Circuit Training
• Combination of exercise stations
• 8 - 12 stations, 3 times through
• Design for different training goals
– Flexibility
– Calisthenics
– Aerobic exercise
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Plyometric Exercise
• Rapid stretch, eccentric contraction
followed by a rapid concentric
contraction to create a forceful
explosive movement
• Rate of stretch vs. magnitude
• Jumps, bounds, medicine ball throws
• Very technical training - skills must be
learned with appropriate technique
• Often develop muscle soreness as a
result of extensive eccentric loading
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Calisthenic Strengthening
Exercises
• Free exercise
• Isotonic training
• Gravity’s involvement determines level
of intensity
• Full range of motion, may incorporate
holding phase
• Pull-ups, push-ups, back extensions,
leg extensions
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Functional Training
• Newer technique used to improve
strength and neuromuscular control
• Involves tri-planar activities designed to
challenge the whole body
– Requires central nervous system to
integrate proprioceptive information from
multiple muscles to produce a specific
movement pattern
• Involves concentric, eccentric and
isometric muscle contractions
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• Allows not only for
development of
strength and control
but also high levels
of core strength and
flexibility
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Training for the Female
Athlete
• Critical for female athlete
• Significant hypertrophy is related to
testosterone present within body
• Remarkable gains are experienced
initially due to enhanced nervous
system and muscle interaction
(efficiency-not muscle bulk)
• Following initial gains, plateau occurs,
with females
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• Males tend to continue to increase
strength with training
• Critical difference is the ratio of strength
to body fat
– Females have reduced strength to body
weight ratio due to higher percentage of
body fat
– Ratio can be enhanced through weight
training
• Results in a decrease in body fat percentage or
an increase in lean weight
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Cardiorespiratory
Endurance
• Perform whole body activities for
extended period of time
• Performance vs. fatigue vs. injury
• Aerobic exercise
– Low intensity exercise that can be sustained
for a long period of time
• Anaerobic exercise
– Activity where intensity is so high that
demand for oxygen is greater than body’s
ability to deliver
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• System’s four components
– Heart
– Lungs
– Blood vessels
– Blood
• Improvements in endurance are the
results of improvements in these 4
components
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Impact on Heart
• Main pumping mechanism
• Increase exercise = increased oxygen
requirement=increase heart pumping
• Heart able to adapt through increases in
heart rate and stroke volume which will
enhance overall cardiac output
• Oxygenation of blood
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What determines how
efficiently the body is using
oxygen?
•
•
•
•
Aerobic capacity = VO2max
More active = higher capacity
Average value = 45-60 ml O2/min/kg
Increases in intensity require higher levels
of oxygen consumption
• Inherit certain range of maximum aerobic
capacity (genetics)
– Dependent on activity levels
– Also impacted by muscle fiber types
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Maximum Aerobic Capacity
• Most accurate techniques must be
performed in a laboratory setting
– Treadmill, bicycle ergometer
– Monitor heart rate and gas exchange at
particular workload
• Generally utilize heart rate to estimate
percentage of maximum aerobic
capacity
– Indirect method
– Heart rate and aerobic capacity have linear
relationship
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Types of Training for
Cardiorespiratory Endurance
• Continuous
– Mode (type of exercise) - must be aerobic in
nature
– Frequency (at least 3 times/week)
– Duration(at least 20 minutes)
– Intensity (monitor intensity as % of heart rate
or perceived exertion)
• Training heart rate – target heart rate
Maximum HR = 220 - Age
• Karvonen formula
– Target HR=Resting HR+(.6 [Max HR – Resting HR])
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• Interval training
– Intermittent activities involving periods of
intense work and active recovery
– Must occur at 60-80% of maximal heart
rate
– Allows for higher intensity training at short
intervals over an extended period of time
– Most anaerobic sports require short burst
which can be mimicked through interval
training
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• Fartlek training
– Cross-country running that originated in
Sweden
– Speed play
– Similar to interval training in the fact activity
occurs over a specific period of time but
pace and speed are not specified
– Consists of varied terrain which
incorporates varying degrees of hills
– Dynamic form of training
– Must elevate heart rate to minimal levels to
be effective
– Popular form of training in off-season
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