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© 2005 The McGraw-Hill Companies, Inc. All rights reserved. Chapter 4: Preventing Injuries Through Fitness Training.

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1 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Chapter 4: Preventing Injuries Through Fitness Training

2 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Fitness is critical for performance and injury prevention Fitness is critical for performance and injury prevention Improper conditioning is a major cause in sports related injuries Improper conditioning is a major cause in sports related injuries Areas of concern: Areas of concern: Flexibility Flexibility Muscular strength, endurance, power Muscular strength, endurance, power Cardiorespiratory endurance Cardiorespiratory endurance Coaches need to develop programs that focus on injury prevention and performance enhancement Coaches need to develop programs that focus on injury prevention and performance enhancement

3 © 2005 The McGraw-Hill Companies, Inc. All rights reserved.

4 Periodization in Training and Conditioning Traditional seasons no longer exist for serious athletes Traditional seasons no longer exist for serious athletes Periodization Periodization Achieve peak performance Achieve peak performance Decrease injuries and overtraining Decrease injuries and overtraining Program that spans various seasons Program that spans various seasons Modify program relative to athlete’s needs Modify program relative to athlete’s needs

5 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Year Round Training Cycle Complete training cycle Complete training cycle Seasonal approach based on preseason, in-season, and off-season 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 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) Broken into periods or phases (lasting weeks or months)

6 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Periods or Phases Transition period: Transition period: Follows last competition (early off-season) Follows last competition (early off-season) Unstructured (escape rigors of training) Unstructured (escape rigors of training) Preparatory period: Preparatory period: Off-season Off-season Hypertropy/endurance phase (Low intensity with high volume) Hypertropy/endurance phase (Low intensity with high volume) Allows for development of endurance base Allows for development of endurance base Lasts several weeks to 2 months Lasts several weeks to 2 months Strength Phase Strength Phase Power Phase (High intensity/ pre-season) Power Phase (High intensity/ pre-season)

7 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Preparatory period (continued) Preparatory period (continued) Strength Phase Strength Phase Intensity and volume increase to moderate levels Intensity and volume increase to moderate levels Power Phase (High intensity/ pre-season) Power Phase (High intensity/ pre-season) Volume is decreased to allow adequate recovery Volume is decreased to allow adequate recovery Competition period: Competition period: May last a < week or several months for seasonal sports May last a < week or several months for seasonal sports High intensity, low volume, skill training sessions High intensity, low volume, skill training sessions May incorporate weekly training cycles (1-7 days) May incorporate weekly training cycles (1-7 days) Designed to ensure peak on days of competition Designed to ensure peak on days of competition

8 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Cross Training Training for a sport with substitutions of alternative activities (carryover value) Training for a sport with substitutions of alternative activities (carryover value) Useful in transition and preparatory periods Useful in transition and preparatory periods Variety to training regimen Variety to training regimen Should be discontinued prior to preseason as it is not sport-specific Should be discontinued prior to preseason as it is not sport-specific

9 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Principles of Conditioning and Training Warm-up/Cool-down Warm-up/Cool-down Motivation Motivation Overload and SAID principle Overload and SAID principle Consistency/routine Consistency/routine Progression Progression Intensity Intensity Specificity Specificity Individuality Individuality Relaxation/Minimize Stress Relaxation/Minimize Stress Safety Safety

10 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Warm-up Precaution against unnecessary musculoskeletal injury and soreness Precaution against unnecessary musculoskeletal injury and soreness May enhance certain aspects of performance May enhance certain aspects of performance Prepares body physiologically for physical work Prepares body physiologically for physical work Stimulates cardiorespiratory system, enhancing circulation and blood flow to muscles Stimulates cardiorespiratory system, enhancing circulation and blood flow to muscles Increases metabolic processes, core temperature, and muscle elasticity Increases metabolic processes, core temperature, and muscle elasticity

11 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. General Activities which bring a general warming to the body(break a sweat) Activities which bring a general warming to the body(break a sweat) Not related to sport Not related to sportSpecific Specific to sport Specific to sport Stretching, jogging, running, throwing, catching Stretching, jogging, running, throwing, catching Should last 10-15 minutes resulting in effects that will last 45 minutes

12 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Cool-down Essential component of workout Essential component of workout Bring body back to resting state Bring body back to resting state 5-10 minutes in duration 5-10 minutes in duration Often ignored Often ignored Decreased muscle soreness following training if time used to stretch after workout Decreased muscle soreness following training if time used to stretch after workout

13 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Why is it important to have good flexibility? Ability to move a joint(s) smoothly through a full range of motion (ROM) Ability to move a joint(s) smoothly through a full range of motion (ROM) Decreased ROM results in: Decreased ROM results in: Decreased performance capabilities Decreased performance capabilities Uncoordinated/awkward movements Uncoordinated/awkward movements Predisposes athlete to injury Predisposes athlete to injury Good flexibility is essential for successful physical performance Good flexibility is essential for successful physical performance Recommended by athletic trainers to prevent injury Recommended by athletic trainers to prevent injury

14 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Factors That Limit Flexibility Bony structures Bony structures Tissue approximation Tissue approximation Excessive fat Excessive fat Muscle and tendon lengths Muscle and tendon lengths Connective tissue Connective tissue Scarring and contractures Scarring and contractures Skin Skin

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16 Range of Motion (ROM) Active range of motion = dynamic flexibility Ability to move a joint with little resistance Ability to move a joint with little resistance Passive range of motion = static flexibility Passive range of motion = static flexibility Motion of joint to end points without muscle contraction Motion of joint to end points without muscle contraction Must be able to move through unrestricted range Must be able to move through unrestricted range Must have elasticity for additional stretch encountered during activity Must have elasticity for additional stretch encountered during activity

17 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Agonist vs. Antagonist Muscles Joints are capable of multiple movements Joints are capable of multiple movements Example: Example: Quadriceps will extend knee with contraction Quadriceps will extend knee with contraction Hamstrings will stretch during extension Hamstrings will stretch during extension Quads (muscle producing movement) referred to as agonist Quads (muscle producing movement) referred to as agonist Muscle undergoing stretch referred to as antagonist Muscle undergoing stretch referred to as antagonist Agonist and antagonist work together to produce smooth coordinated movements Agonist and antagonist work together to produce smooth coordinated movements

18 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Stretching Techniques Ballistic Bouncing movement in which repetitive contractions of agonist work to stretch antagonist muscle Bouncing movement in which repetitive contractions of agonist work to stretch antagonist muscle While effective in improving flexibility, caution should be exercised While effective in improving flexibility, caution should be exercised Possible soreness (soccer example) Possible soreness (soccer example)

19 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Static stretching Passively stretching Passively stretching 20-30 second hold = optimal 20-30 second hold = optimal Go to point of pain and back off and hold for 30 seconds (3 to 4 times) Go to point of pain and back off and hold for 30 seconds (3 to 4 times) Controlled, less chance of injury Controlled, less chance of injury Not dynamic Not dynamic Should precede ballistic stretching Should precede ballistic stretching

20 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Proprioceptive Neuromuscular Facilitation Physical therapy for neuromuscular paralysis Physical therapy for neuromuscular paralysis Slow-reversal-hold-relax Slow-reversal-hold-relax Contract-relax Contract-relax Hold-relax Hold-relax Ten second push, ten second relax Ten second push, ten second relax Best technique to improve flexibility Best technique to improve flexibility Technique that involves combination of alternating contractions and relaxation of both agonist and antagonists Technique that involves combination of alternating contractions and relaxation of both agonist and antagonists

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22 Assessment of Flexibility Various devices have been designed to accommodate joint sizes and complexities of movement Various devices have been designed to accommodate joint sizes and complexities of movement Goniometer most widely used device Goniometer most widely used device Can also utilize the following tests: Can also utilize the following tests: Trunk hip flexion test Trunk hip flexion test Trunk extension test Trunk extension test Shoulder extension test Shoulder extension test

23 © 2005 The McGraw-Hill Companies, Inc. All rights reserved.

24 Is there a relationship between strength and flexibility? Co-exist Co-exist Muscle bound = zero flexibility Muscle bound = zero flexibility Strength training will provide individual with ability to develop dynamic flexibility through full range of motion Strength training will provide individual with ability to develop dynamic flexibility through full range of motion Develop more powerful and coordinated movements Develop more powerful and coordinated movements

25 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Flexibility, Muscular Strength, Endurance, and Power

26 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Muscle Strength, Power, and Endurance Strength: ability to generate force against resistance Muscular endurance: repetitive muscular contractions (increase strength = increase endurance Power: the relationship between strength and time

27 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Muscle Contractions Isometric contraction Isometric contraction No length change occurs during contraction No length change occurs during contraction Isotonic contraction Isotonic contraction Concentric- shortening of muscle with contraction in an effort to overcome more resistance 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 Eccentric - lengthening of muscle with contraction because load is greater than force being produced Both are considered dynamic movements Both are considered dynamic movements

28 © 2005 The McGraw-Hill Companies, Inc. All rights reserved.

29 Factors that Determine Levels of Muscular Strength Size of muscle: Size of muscle: Function of diameter and of muscle fibers Function of diameter and of muscle fibers Hypertrophy vs. Atrophy Hypertrophy vs. Atrophy Number of muscle fibers Number of muscle fibers Neuromuscular efficiency Neuromuscular efficiency Initial gains are due to increased efficiency Initial gains are due to increased efficiency More effectively engage specific motor units More effectively engage specific motor units Biomechanical factors Biomechanical factors Bones and muscles = Levers and pulleys Bones and muscles = Levers and pulleys

30 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Fast-Twitch vs. Slow-Twitch Muscle Fibers Fast-Twitch vs. Slow-Twitch Muscle Fibers Motor units with distinct metabolic and contractile capability Motor units with distinct metabolic and contractile capability Individual make-up Muscles contain both types of fibers Muscles contain both types of fibers Muscle functioning impacts ratios (postural vs. powerful movement) Muscle functioning impacts ratios (postural vs. powerful movement) Genetically determined Genetically determined Slow twitch (Type I): Slow twitch (Type I): Generally major constituent of postural muscles Generally major constituent of postural muscles Fast twitch (Type II) Fast twitch (Type II) High force in short amount of time High force in short amount of time Produce powerful movements Produce powerful movements

31 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Levels of Physical Activity Levels of Physical Activity Will influence increase/decrease in muscle strength Will influence increase/decrease in muscle strength Also impacts cardiorespiratory fitness, flexibility and increases in body fat Also impacts cardiorespiratory fitness, flexibility and increases in body fat Overtraining Overtraining Psychological and physiological breakdown Psychological and physiological breakdown Signs Signs Apathy, loss of appetite, staleness, declines in performance, weight loss, inability to sleep Apathy, loss of appetite, staleness, declines in performance, weight loss, inability to sleep Prevent through appropriate training protocol, proper diet, and rest Prevent through appropriate training protocol, proper diet, and rest

32 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. What physiological changes occur to cause increased strength? Multiple theories of muscle hypertrophy Multiple theories of muscle hypertrophy Primary explanation of muscle hypertrophy: Primary explanation of muscle hypertrophy: Increase in protein myofilament number and size Increase in protein myofilament number and size Continued need for additional research Continued need for additional research

33 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Core Stabilization Training Core refers to muscles that make up center of body Core refers to muscles that make up center of body Low back, pelvis, hips, abdomen Low back, pelvis, hips, abdomen Works to stabilize body enabling muscles of extremity to function optimally Works to stabilize body enabling muscles of extremity to function optimally Weak core is a fundamental problem of inefficient movements = injury Weak core is a fundamental problem of inefficient movements = injury Program targets strength, neuromuscular control, power, and endurance of the core Program targets strength, neuromuscular control, power, and endurance of the core Program will stress multiple planes and incorporate various resistance techniques Program will stress multiple planes and incorporate various resistance techniques

34 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Techniques of Resistance Training Progressive resistance exercise Progressive resistance exercise Overload principle must be applied Overload principle must be applied Must work muscle at increasingly higher intensities to enhance strength over time 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 If intensity of training does not increase, but training continues, muscle strength will be sustained

35 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Contraction where muscle length remains unchanged Contraction where muscle length remains unchanged Muscle contraction that lasts 10 seconds and should be perform 5-10 times/daily Muscle contraction that lasts 10 seconds and should be perform 5-10 times/daily Pro: quick, effective, cheap, good for rehab Pro: quick, effective, cheap, good for rehab Con: only works at one point in ROM, produces spiking of blood pressure due to Valsalva maneuver Con: only works at one point in ROM, produces spiking of blood pressure due to Valsalva maneuver Isometric Exercise

36 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Concentric and eccentric training should be incorporated for greatest strength improvement 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 Concentric phase of lift should last 1-2 seconds; eccentric phase 2-4 seconds Variations exist between free and machine weight lifting Variations exist between free and machine weight lifting Motion restrictions, levels of muscular control required, amount of weight that can be lifted Motion restrictions, levels of muscular control required, amount of weight that can be lifted Equipment design, varying resistances Equipment design, varying resistances

37 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Terminology associated with weight training Terminology associated with weight training Repetitions Repetitions Repetition maximum Repetition maximum One repetition maximum One repetition maximum Set Set Intensity Intensity Recovery period Recovery period Frequency Frequency Progressive Resistance Exercise Techniques

38 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. When training should be able to perform 3 sets of 6-8 repetitions When training should be able to perform 3 sets of 6-8 repetitions Increases should occur in increments of 10% 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 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) Training of a particular muscle group should occur 3-4 times per week (not on successive days)

39 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Muscular Endurance vs. Strength Training for endurance enhances strength and vice versa Training for endurance enhances strength and vice versa Training for strength should involve lower repetitions at heavier weight Training for strength should involve lower repetitions at heavier weight Training for endurance requires lower weight at 12-15 repetitions Training for endurance requires lower weight at 12-15 repetitions

40 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Open vs. Closed Kinetic Chain Exercises Anatomical functional relationship for upper and lower extremities Anatomical functional relationship for upper and lower extremities OKC OKC When foot or hand are not in contact with the ground or supporting surface When foot or hand are not in contact with the ground or supporting surface CKC CKC Foot or hand are weight bearing Foot or hand are weight bearing Widely used = more functional Widely used = more functional

41 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Isokinetic Training Muscle contraction at a constant velocity Muscle contraction at a constant velocity Maximal and constant resistance throughout the full range of motion Maximal and constant resistance throughout the full range of motion Maximal effort = Maximal strength gains Maximal effort = Maximal strength gains Rehab Rehab Never widely used in strength training Never widely used in strength training Losing popularity in rehabilitation settings Losing popularity in rehabilitation settings

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43 Circuit Training Combination of exercise stations Combination of exercise stations 8 - 12 stations, 3 times through 8 - 12 stations, 3 times through Design for different training goals Design for different training goals Flexibility Flexibility Calisthenics Calisthenics Aerobic exercise Aerobic exercise

44 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Plyometric Exercise Rapid stretch, eccentric contraction followed by a rapid concentric contraction to create a forceful explosive movement Rapid stretch, eccentric contraction followed by a rapid concentric contraction to create a forceful explosive movement Rate of stretch vs. magnitude Rate of stretch vs. magnitude Jumps, bounds, medicine ball throws Jumps, bounds, medicine ball throws Very technical training - skills must be learned with appropriate technique Very technical training - skills must be learned with appropriate technique Often develop muscle soreness as a result of extensive eccentric loading Often develop muscle soreness as a result of extensive eccentric loading

45 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Calisthenic Strengthening Exercises Free exercise Free exercise Isotonic training Isotonic training Gravity’s involvement determines level of intensity Gravity’s involvement determines level of intensity Full range of motion, may incorporate holding phase Full range of motion, may incorporate holding phase Pull-ups, push-ups, back extensions, leg extensions Pull-ups, push-ups, back extensions, leg extensions

46 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Training for the Female Athlete Critical for female athlete Critical for female athlete Significant hypertrophy is related to testosterone present within body 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) Remarkable gains are experienced initially due to enhanced nervous system and muscle interaction (efficiency-not muscle bulk) Following initial gains, plateau occurs, with females Following initial gains, plateau occurs, with females

47 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Males tend to continue to increase strength with training Males tend to continue to increase strength with training Critical difference is the ratio of strength to body fat 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 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 Ratio can be enhanced through weight training and decrease in body fat percentage/increased lean weight

48 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Cardiorespiratory Endurance Perform whole body activities for extended period of time Perform whole body activities for extended period of time Performance vs. fatigue vs. injury Performance vs. fatigue vs. injury Aerobic exercise Aerobic exercise Low intensity exercise that can be sustained for a long period of time Low intensity exercise that can be sustained for a long period of time Anaerobic exercise Anaerobic exercise Activity where intensity is so high that demand for oxygen is greater than body’s ability to deliver Activity where intensity is so high that demand for oxygen is greater than body’s ability to deliver

49 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. System’s four components System’s four components Heart Heart Lungs Lungs Blood vessels Blood vessels Blood Blood Improvements in endurance are the results of improvements in these 4 components Improvements in endurance are the results of improvements in these 4 components

50 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Impact on Heart Main pumping mechanism Main pumping mechanism Increase exercise = increased oxygen requirement=increase heart pumping 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 Heart able to adapt through increases in heart rate and stroke volume which will enhance overall cardiac output Oxygenation of blood Oxygenation of blood

51 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. What determines how efficiently the body is using oxygen? Aerobic capacity = VO 2 max Aerobic capacity = VO 2 max More active = higher capacity More active = higher capacity Average value = 45-60 ml O 2 /min/kg Average value = 45-60 ml O 2 /min/kg Increases in intensity require higher levels of oxygen consumption Increases in intensity require higher levels of oxygen consumption Inherit certain range of maximum aerobic capacity (genetics) Inherit certain range of maximum aerobic capacity (genetics) Dependent on activity levels Dependent on activity levels Also impacted by muscle fiber types Also impacted by muscle fiber types

52 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Maximum Aerobic Capacity Most accurate techniques must be performed in a laboratory setting Most accurate techniques must be performed in a laboratory setting Treadmill, bicycle ergometer Treadmill, bicycle ergometer Monitor heart rate and gas exchange at particular workload Monitor heart rate and gas exchange at particular workload Generally utilize heart rate to estimate percentage of maximum aerobic capacity Generally utilize heart rate to estimate percentage of maximum aerobic capacity Indirect method Indirect method Heart rate and aerobic capacity have linear relationship Heart rate and aerobic capacity have linear relationship

53 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Types of Training for Cardiorespiratory Endurance Continuous Continuous Mode (type of exercise) - must be aerobic in nature Mode (type of exercise) - must be aerobic in nature Frequency (at least 3 times/week) Frequency (at least 3 times/week) Duration(at least 20 minutes) Duration(at least 20 minutes) Intensity (monitor intensity as % of heart rate or perceived exertion) Intensity (monitor intensity as % of heart rate or perceived exertion) Training heart rate – target heart rate Training heart rate – target heart rate Maximum HR = 220 - Age Karvonen formula Karvonen formula Target HR=Resting HR+(.6 [Max HR – Resting HR)] Target HR=Resting HR+(.6 [Max HR – Resting HR)]

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55 Interval training Interval training Intermittent activities involving periods of intense work and active recovery Intermittent activities involving periods of intense work and active recovery Must occur at 60-80% of maximal heart rate Must occur at 60-80% of maximal heart rate Allows for higher intensity training at short intervals over an extended period of time 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 Most anaerobic sports require short burst which can be mimicked through interval training

56 © 2005 The McGraw-Hill Companies, Inc. All rights reserved. Fartlek training Fartlek training Cross-country running that originated in Sweden Cross-country running that originated in Sweden Speed play Speed play Similar to interval training in thct activity occurs over a specific period of time but pace and speed are not specified Similar to interval training in thct 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 Consists of varied terrain which incorporates varying degrees of hills Dynamic form of training Dynamic form of training Must elevate heart rate to minimal levels to be effective Must elevate heart rate to minimal levels to be effective Popular form of training in off-season Popular form of training in off-season


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