Copyright © 2012 American College of Sports Medicine Chapter 10 Warm-Up and Flexibility

Copyright © 2012 American College of Sports Medicine Warm-Up Overview –Performing low-intensity exercise to prepare the body for more intense physical activity –Increases in intensity progressively –Passive vs. active –General vs. specific –Increases muscle temperature –Should last 5-15 minutes

Copyright © 2012 American College of Sports Medicine Examples of General & Specific Warm-Ups

Copyright © 2012 American College of Sports Medicine Warm-Up (cont’d) Physiology of Warming Up –  Muscle & core temp –  Blood flow –  Speed of metabolic reactions –  Release of O 2 from hemoglobin & myoglobin –  Heart rate & cardiac output –  Nerve conduction velocity & neural activation –  O 2 consumption –  Joint/CT & skeletal muscle viscosity & resistance –  Muscle glycogen breakdown & glycolysis –  Mental preparedness & psychological functioning

Copyright © 2012 American College of Sports Medicine Warm-Up (cont’d) Performance Effects –After 3-5 min of warm-up, enhanced performance in: Vertical jump Swimming time Running time Cycling power –Key elements of warm-up Increase muscle temperature Increase V O 2 Minimize fatigue

Copyright © 2012 American College of Sports Medicine Warm-Up (cont’d) Warm-Up Versus Postactivation Potentiation –Potentiation protocol Activated motor units stay facilitated for a period of time following maximal or near-maximal muscle contractions Muscle strength, power, & endurance can be enhanced Viewed by some as a warm-up Viewed by others as a separate entity & part of workout

Copyright © 2012 American College of Sports Medicine The Warm-Up Continuum

Copyright © 2012 American College of Sports Medicine Warm-Up (cont’d) Dynamic Versus Static Warm-Ups –Dynamic warm-up: enhances performance –Static warm-up Shown to reduce performance when performed before activity by itself Light stretching coupled with dynamic warm-up may be effective to optimize performance Intense stretching recommended for strength/power athletes after workout, in cooldown

Copyright © 2012 American College of Sports Medicine Flexibility Overview –A measure of joint ROM without injury –An important health-related component of fitness –Types Static flexibility Dynamic flexibility Ballistic flexibility

Copyright © 2012 American College of Sports Medicine Flexibility (cont’d) Health Benefits –Maintains appropriate muscle lengths –Improves muscle balance –Improves muscular weakness –Reduces risk of injury –Improves posture –Improves ability to move –Relieves stress –Reduces risk of low-back pain

Copyright © 2012 American College of Sports Medicine Flexibility (cont’d) Improvements in Athletic Skills –Olympic weightlifter: proper overhead position in the snatch –Gymnast: proper position during a split –Ice hockey goalie: blocking the puck at many difficult angles –Tennis player: maximizing velocity & accuracy of serve –Volleyball player: blocking a shot & spiking the ball –Hurdler: elevating over the hurdle w/o deviation in stride

Copyright © 2012 American College of Sports Medicine Flexibility (cont’d) Flexibility and Injury Prevention –May decrease risk of pain & injury –Increases compliance of tendon –Reduces acute tendon stiffness –Decreases hysteresis –Enhances joint ROM

Copyright © 2012 American College of Sports Medicine Flexibility (cont’d) Factors Affecting Flexibility –Joint structure –Muscular imbalance –Muscular control –Age –Gender –CT (tendons, ligaments, fascia, joint capsules, & skin) –Bulk –Training in a limited ROM –Activity level

Copyright © 2012 American College of Sports Medicine Flexibility (cont’d) Types of Stretching –Static –Dynamic –Proprioceptive neuromuscular facilitation (PNF) Hold-relax Contract-relax Hold-relax with agonist contraction Contract-relax with agonist contraction

Copyright © 2012 American College of Sports Medicine Flexibility (cont’d) Flexibility Training Guidelines –Stretch after workout or after general warm-up –Select stretches that work each major muscle group –Stretch for at least 10 minutes –Perform at least 4 reps/muscle group at least 2-3 days per week –Select dynamic, static, or PNF stretches –Consider ballistic stretching for athletes in explosive sports –Take static stretches to point of mild discomfort & hold sec –Allow a 6-sec contraction followed by a sec assisted stretch for PNF stretches

Copyright © 2012 American College of Sports Medicine The Cooldown Is a postworkout light exercise activity Example: 5-10 min of walking/cycling Provides an adjustment period between exercise & rest Helps return body to homeostasis in a controlled manner Facilitates waste removal Reduces cardiovascular responses appropriately Institutes a greater sense of well-being Provides time for stretching to increase flexibility