Warm-Up and Stretching

Ian Jeffreys, MS; CSCS,*D; NSCA-CPT,*D

chapter

13Warm-Upand Stretching

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

Figures 13.1 and 13.2

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

Figures 13.3, 13.4, and 13.5

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

Figures 13.6, 13.7, and 13.8

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

Figures 13.9, 13.10, and 13.11

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

Figures 13.12 and 13.13

Figures 13.14, 13.15, and 13.16

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.