Chapter 4: Preventing Injuries

Through Fitness Training

• 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 programs that focus on injury prevention and performance enhancement

Periodization in Training Periodization in Training and Conditioningand 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

Year Round Training Year Round Training CycleCycle

• 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)

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

• 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

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

Principles of Conditioning and

Training• Warm-up/Cool-

down

• Motivation

• Overload and SAID principle

• Consistency/ routine

• Progression

• Intensity • Specificity

• Individuality

• Relaxation/ Minimize Stress

• Safety

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

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

Cool-down

• 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

Why is it important to have good flexibility?

• Ability to move a joint(s) smoothly through a full range of motion (ROM)

• Decreased ROM results in: – Decreased performance capabilities– Uncoordinated/awkward movements– Predisposes athlete to injury

• Good flexibility is essential for successful physical performance

• Recommended by athletic trainers to prevent injury

Factors That Limit Flexibility

• Bony structures• Tissue approximation• Excessive fat• Muscle and tendon lengths• Connective tissue• Scarring and contractures• Skin

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

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

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

– Possible soreness (soccer example)

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

Proprioceptive Neuromuscular Facilitation– 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

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

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

Flexibility, Muscular Strength,

Endurance, and Power

Muscle Strength, Power, Muscle Strength, Power, and Enduranceand Endurance

Strength: ability to generate force against resistance

Muscular endurance: repetitive muscular contractions (increase strength = increase endurance)

Power: the relationship between strength and time

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

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

• Fast-Twitch vs. Slow-Twitch Muscle Fibers• Motor units with distinct metabolic and contractile

capabilityIndividual 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

• 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

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

Core Stabilization Training

• Core refers to muscles that make up center of body– Low back, pelvis, hips, abdomen

• Works to stabilize body enabling muscles of extremity to function optimally

• Weak core is a fundamental problem of inefficient movements = injury

• Program targets strength, neuromuscular control, power, and endurance of the core

• Program will stress multiple planes and incorporate various resistance techniques

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

• Contraction where muscle length remains unchanged

• Muscle contraction that lasts 10 seconds and should be perform 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

Isometric Exercise

• 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

• Terminology associated with weight training– Repetitions– Repetition maximum– One repetition maximum– Set– Intensity– Recovery period– Frequency

Progressive Resistance Exercise Techniques

• 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)

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

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

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

Circuit Training

• Combination of exercise stations• 8 - 12 stations, 3 times through• Design for different training goals

– Flexibility– Calisthenics– Aerobic exercise

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

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

• 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 and decrease in body fat percentage/increased lean weight

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

• System’s four components

– Heart– Lungs– Blood vessels– Blood

• Improvements in endurance are the results of improvements in these 4 components

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

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

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

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 (60% HR Max)– Target HR=Resting HR+(.6 [Max HR – Resting HR)]

• 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

• Fartlek training– Cross-country running that originated in Sweden – Speed play– Similar to interval training in that 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