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Warm-Up and Stretching. chapter 13. Warm-Up and Stretching. Ian Jeffreys, MS; CSCS,*D; NSCA-CPT,*D. Chapter Objectives . Identify the benefits and components of a preexercise warm-up. Assess the suitability of performing stretch-ing exercises for a warm-up.
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Warm-Up and Stretching chapter13 Warm-Upand Stretching Ian Jeffreys, MS; CSCS,*D; NSCA-CPT,*D
Chapter Objectives • Identify the benefits and components of a preexercise warm-up. • Assess the suitability of performing stretch-ing exercises for a warm-up. • Identify factors that affect flexibility. (continued)
Chapter Objectives (continued) • Describe flexibility exercises that take advantage of proprioceptive neuromuscular facilitation. • Explain the mechanisms that cause the muscular inhibition that improves the stretch. • Select and apply appropriate static and dynamic stretching methods.
Section Outline • Warm-Up • Stretching During Warm-Up • Components of a Warm-Up
Warm-Up • Warming up can have the following positive impacts on performance: • Faster muscle contraction and relaxation of both agonist and antagonist muscles • Improvements in the rate of force development and reaction time • Improvements in muscle strength and power • Lowered viscous resistance in muscles (continued)
Warm-Up • Warming up can have the following positive impacts on performance (continued): • Improved oxygen delivery due to the Bohr effect whereby higher temperatures facilitate oxygen release from hemoglobin and myoglobin • Increased blood flow to active muscles • Enhanced metabolic reactions
Warm-Up • Stretching During Warm-Up • Research suggests dynamic stretching is the preferred option for stretching during warm-up. • Consider the range of motion and stretch-shortening cycle requirements of the sport when designing a warm-up.
Warm-Up • Components of a Warm-Up • A general warm-up period may consist of 5 to 10 minutes of slow activity such as jogging or skipping. • A specific warm-up period incorporates movements similar to the movements of the athlete’s sport. It involves 8 to 12 minutes of dynamic stretching focusing on movements that work through the range of motion required for the sport.
Section Outline • Flexibility • Flexibility and Performance • Factors Affecting Flexibility • Joint Structure • Age and Sex • Connective Tissue • Resistance Training With Limited Range of Motion • Muscle Bulk • Activity Level • Frequency, Duration, and Intensity of Stretching • When Should an Athlete Stretch? • Proprioceptors and Stretching
Flexibility • Flexibility is a measure of range of motion (ROM) and has static and dynamic compo-nents. • Static flexibility is the range of possible movement about a joint and its surrounding muscles during a passive movement. • Dynamic flexibility refers to the available ROM during active movements and therefore requires voluntary muscular actions.
Flexibility • Flexibility and Performance • Optimal levels of flexibility exist for each activity. • Injury risk may increase outside this range.
Flexibility • Factors Affecting Flexibility • Joint Structure • Structure determines the joint’s range of motion. • Age and Sex • Older people tend to be less flexible than younger people;females tend to be more flexible than males. • Connective Tissue • Elasticity and plasticity of connective tissues affect ROM. (continued)
Flexibility • Factors Affecting Flexibility (continued) • Resistance Training With Limited Range of Motion • Exercise through a full ROM and develop both agonist and antagonist muscles to prevent loss of ROM. • Muscle Bulk • Large muscles may impede joint movement. • Activity Level • An active person tends to be more flexible than an inactive one, but activity alone will not improve flexibility.
Flexibility • Frequency, Duration, and Intensity of Stretching • Acute effects of stretching on ROM are transient. • For longer-lasting effects, a stretching program is required.
Flexibility • When Should an Athlete Stretch? • Following practice and competition • Postpractice stretching facilitates ROM improvements because of increased muscle temperature. • Stretching should be performed within 5 to 10 minutes after practice. • Postpractice stretching may also decrease muscle soreness although the evidence on this is ambiguous.
Flexibility • When Should an Athlete Stretch? • As a separate session • If increased levels of flexibility are required, additional stretching sessions may be needed. • In this case, stretching should be preceded by a thorough warm-up to allow for the increase in muscle temperature necessary for effective stretching. • This type of session can be especially useful as a recovery session on the day after a competition.
Flexibility • Proprioceptors and Stretching • Stretch reflex • A stretch reflex occurs when muscle spindles are stimulated during a rapid stretching movement. • This should be avoided when stretching, as it will limit motion.
Flexibility • Proprioceptors and Stretching • Autogenic inhibition and reciprocal inhibition • Autogenic inhibition is accomplished via active contraction before a passive stretch of the same muscle. • Reciprocal inhibition is accomplished by contracting the muscle opposing the muscle that is being passively stretched. • Both result from stimulation of Golgi tendon organs, which cause reflexive muscle relaxation.
Section Outline • Types of Stretching • Static Stretch • Ballistic Stretch • Dynamic Stretch • Proprioceptive Neuromuscular Facilitation Stretch • Hold-Relax • Contract-Relax • Hold-Relax With Agonist Contraction • Common PNF Stretches With a Partner
Types of Stretching • Static Stretch • A static stretch is slow and constant, with the end position held for 30 seconds. • Ballistic Stretch • A ballistic stretch typically involves active muscular effort and uses a bouncing-type movement in which the end position is not held. • Dynamic Stretch • A dynamic stretch is a type of functionally based stretching exercise that uses sport-specific move-ments to prepare the body for activity.
Types of Stretching • Proprioceptive Neuromuscular Facilitation (PNF) Stretch • Hold-Relax • Passive prestretch (10 seconds), isometric hold (6 seconds), passive stretch (30 seconds)
Positions for PNF Hamstring Stretch • Figures 13.1 and 13.2 (next slide) • Starting position of PNF hamstring stretch • Partner and subject leg and hand positions for PNF hamstring stretch
Hold-Relax • Figures 13.3, 13.4, and 13.5 (next slide) • Passive prestretch of hamstrings during hold-relax PNF hamstring stretch • Isometric action during hold-relax PNF hamstring stretch • Increased ROM during passive stretch of hold-relax PNF hamstring stretch
Types of Stretching • Proprioceptive Neuromuscular Facilitation Stretch • Contract-Relax • Passive prestretch (10 seconds), concentric muscle action through full ROM, passive stretch (30 seconds)
Contract-Relax • Figures 13.6, 13.7, and 13.8 (next slide) • Passive prestretch of hamstrings during contract-relax PNF stretch • Concentric action of hip extensors during contract-relax PNF stretch • Increased ROM during passive stretch of contract-relax PNF stretch
Types of Stretching • Proprioceptive Neuromuscular Facilitation Stretch • Hold-Relax With Agonist Contraction • During third phase (passive stretch), concentric action of the agonist used to increase the stretch force
Hold-Relax With Agonist Contraction • Figures 13.9, 13.10, and 13.11 (next slide) • Passive prestretch during hold-relax with agonist contraction PNF hamstring stretch • Isometric action of hamstrings during hold-relax with agonist contraction PNF hamstring stretch • Concentric contraction of quadriceps during hold-relax with agonist contraction PNF hamstring stretch, creating increased ROM during passive stretch
Key Point • The hold-relax with agonist contraction is the most effective PNF stretching technique due to facilitation via both reciprocal and autogenic inhibition.
Types of Stretching • Proprioceptive Neuromuscular Facilitation Stretch • Common PNF Stretches With a Partner • Calf and ankle • Chest • Groin • Hamstrings and hip extensors • Quadriceps and hip flexors • Shoulder
Partner PNF Stretching • Figures 13.12-13.16 (next two slides) • Partner PNF stretching for the: • Calves • Chest • Groin • Quadriceps and hip flexors • Shoulders
Types of Stretching • Guidelines for Static Stretching • Get into a position that facilitates relaxation. • Move to the point in the ROM where you experience a sensation of mild discomfort. If performing partner-assisted PNF stretching, communicate clearly with your partner. • Hold stretches for 30 seconds. • Repeat unilateral stretches on both sides.
Types of Stretching • Precautions for Static Stretching • Decrease stretch intensity if you experience pain, radiating symptoms, or loss of sensation. • Use caution when stretching a hypermobile joint. • Avoid combination movements that involve the spine (e.g., extension and lateral flexion). • Stabilizing muscles should be active to protect other joints and prevent unwanted movements.
Types of Stretching • Guidelines for Dynamic Stretching • Carry out 5 to 10 repetitions for each movement, either in place or over a given distance. • Progressively increase the ROM on each repetition. • Increase the speed of motion on subsequent sets where appropriate. • Contract the muscles as you move through the ROM.
Types of Stretching • Precautions for Dynamic Stretching • Move progressively through the ROM. • Move deliberately but without bouncing (movement must be controlled at all times). • Do not forsake good technique for additional ROM.