Chapter 4: Preventing Injuries Through Fitness Training © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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) © 2010 McGraw-Hill Higher Education. All rights reserved. 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) © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. Foundations of Conditioning and Training • Warm-up/Cool-down • Motivation • Overload and SAID principle • Intensity • Specificity • Individuality • Consistency/routine • Relaxation/Minimize Stress • Progression • Safety © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. Factors That Limit Flexibility • • • • • • • Bony structures Tissue approximation Excessive fat Muscle and tendon lengths Connective tissue Scarring and contractures Skin © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. Stretching Exercises Shoulder Towel Stretch Exercise © 2010 McGraw-Hill Higher Education. All rights reserved. Anterior Abdominal Stretch William’s Flexion Exercises © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. © 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 © 2010 McGraw-Hill Higher Education. All rights reserved. Flexibility Assessments Trunk & Hip Flexion Test Trunk Extension Test Shoulder Lift Test © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. Muscular Strength, Endurance, and Power © 2010 McGraw-Hill Higher Education. 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: is the relationship between strength and time © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. © 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. Progressive Resistance Exercise Techniques • Terminology associated with weight training – Repetitions – Repetition maximum – One repetition maximum – Set – Intensity – Recovery period – Frequency © 2010 McGraw-Hill Higher Education. All rights reserved. • 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) © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. Strengthening Exercises Bench Press Shoulder Rotation © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. Leg Exercises © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. Circuit Training • Combination of exercise stations • 8 - 12 stations, 3 times through • Design for different training goals – Flexibility – Calisthenics – Aerobic exercise © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • Allows not only for development of strength and control but also high levels of core strength and flexibility © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • System’s four components – Heart – Lungs – Blood vessels – Blood • Improvements in endurance are the results of improvements in these 4 components © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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 © 2010 McGraw-Hill Higher Education. All rights reserved. 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]) © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved. • 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 © 2010 McGraw-Hill Higher Education. All rights reserved.