1. PE 254 Developing a Flexibility Program (Chapter 9)

2. Flexibility The ability of a joint to move through its full range of motion (ROM) Important for general fitness and wellness Static versus dynamic flexibility

3. What Determines Flexibility? Joint structure—joints vary in direction and range of movement Joint capsules = semielastic structures that give joints strength and stability but limit movement Muscle elasticity and length Collagen = white fibers that provide structure and support Elastin = yellow fibers that are elastic and flexible Titin = muscle filament with elastic properties

4. Muscle Elasticity and Length

5. Muscle Architecture

6. Force -Length and Muscle Architecture

7. Force - Velocity and Muscle Architecture

8. Effect of Stretch on Connective Tissue

9. Efferent vs. Afferent Efferent neural signals produce muscle contraction. Afferent neural signals provide the brain with signals from the senses.

10. Sensory Innervation - Muscle Spindle

11. Sensory Innervation Golgi Tendon Organ

12. Nervous System Activity Stretch receptors control muscle length If a muscle is stretched, receptors send a message to the spinal cord, which then sends a signal back to the muscle telling it to contract A strong muscle contraction produces an opposite reflex that causes the muscle to relax Proprioceptive neuromuscular facilitation (PNF) = a technique for stretching muscles that relies on neuromuscular reflexes to stimulate training effects

13. Types of Stretching Techniques Static stretching = slowly stretching a muscle and holding the stretched position Ballistic stretching = suddenly stretching a muscle through a bouncing or swinging movement Proprioceptive neuromuscular facilitation = obtaining a greater training effect by using neuromuscular reflexes; for example, contracting a muscle before it is stretched

14. Types of Stretching Techniques Passive stretching = muscles are stretched by force applied by an outside source Active stretching = muscles are stretched by a contraction of the opposing muscles Safest technique is active static stretching, with an occasional passive assist http://video.google.com/videosearch?q=flexibility+training+exercises&hl=en&emb=0&aq=5&oq=flexibility+# http://www.youtube.com/watch?v=MdzdH_O1riw

15. How to Perform a PNF Stretch The process of performing a PNF stretch involves the following. The muscle group to be stretched is positioned so that the muscles are stretched and under tension. The individual then contracts the stretched muscle group for 5 - 6 seconds while a partner, or immovable object, applies sufficient resistance to inhibit movement. Please note; the effort of contraction should be relevant to the level of conditioning. The contracted muscle group is then relaxed and a controlled stretch is applied for about 30 seconds. The muscle group is then allowed 30 seconds to recover and the process is repeated 2 - 4 times.

16. The athlete and partner assume the position for the stretch, and then the partner extends the body limb until the muscle is stretched and tension is felt. The athlete then contracts the stretched muscle for 5 - 6 seconds and the partner must inhibit all movement. (The force of the contraction should be relevant to the condition of the muscle. For example, if the muscle has been injured, do not apply a maximum contraction). The muscle group is relaxed, then immediately and cautiously pushed past its normal range of movement for about 30 seconds. Allow 30 seconds recovery before repeating the procedure 2 - 4 times.

17. Benefits of Flexibility and Stretching Exercises Joint health Prevention of low-back pain and injuries Other potential benefits: Temporary reduction of postexercise muscle soreness, known as delayed-onset muscle soreness (DOMS) Relief of aches and pains and muscle cramps Improved body position and strength for sports Maintenance of good posture and balance Relaxation Lifetime wellness benefits Assessment Issues

18. Creating a Successful Program to Develop Flexibility Applying the FITT principle: F requency—how often to stretch I ntensity—how far to stretch T ime—how long to stretch T ype—which stretching exercises to perform

19. Frequency of Exercise The American College of Sports Medicine (ACSM) recommends that stretching exercises be performed a minimum of 2–3 days per week Stretch when muscles are warm, either after a workout or after the active part of a warm-up Do not stretch before a high-performance activity

20. Intensity and Time (Duration) of Exercise Stretch to the point of slight tension or mild discomfort Hold each stretch for 10–30 seconds Do at least 4 repetitions of each exercise Rest for 30–60 seconds between stretches

21. A Flexibility Workout

22. Flexibility Exercises Sample Flexibility Exercises Warm up 3-5 minutes before stretching Stretch to a point of mild tension Exhale as you move into the stretch; remember not to hold your breath Prevent bouncing movement when stretching Hold each stretch for 10 to 30 seconds Repeat each stretch 3 to 5 times Dynamic stretching = pre-exercise Static stretching = post exercise

23. Low-Back Health Function of the spine Provides structural support for the body Surrounds and protects the spinal cord Supports body weight Serves as attachment site for muscles, tendons, ligaments Allows movement of neck and back in all directions

24. Skeletal System

25. Structure of the Spine 7 cervical vertebrae in the neck 12 thoracic vertebrae in the upper back 5 lumbar vertebrae in the lower back 9 vertebrae at the base of the spine fused into the sacrum and the coccyx (tailbone)

26. Structure of the Spine

27. Vertebrae Vertebrae consist of a body, an arch, and several bony processes Intervertebral disks = elastic disks located between adjoining vertebrae; consist of a gel- and water-filled nucleus surrounded by fibrous rings; serve as shock absorbers Nerve roots = base of pairs of spinal nerves that branch off the spinal cord

28. Vertebrae and Intervertebral Disk

29. Causes of Back Pain Any movement that causes excessive stress Risk factors: Age greater than 34 years Degenerative diseases Family or personal history of back trauma Sedentary lifestyle, overweight Low job satisfaction, certain occupations Low socioeconomic status Smoking Psychological stress or depression

30. Underlying Causes of Back Pain Poor muscle endurance and strength Poor posture Poor body mechanics

32. Preventing Low-Back Pain Lose weight, stop smoking, and reduce emotional stress Avoid sitting, standing, or working in the same position for too long Use a supportive seat and a medium-firm mattress Warm up thoroughly before exercise Progress gradually when improving strength and fitness

33. Protecting Your Back

35. Managing Acute Back Pain Sudden back pain usually involves tissue injury Symptoms: Pain, muscle spasms, stiffness, inflammation Treatment: Ice, then heat OTC medication (ibuprofen or naproxen) Moderate exercise

36. Managing Chronic Back Pain Considered chronic if lasts longer than 3 months Symptoms: Stabbing or shooting pain, steady ache accompanied by stiffness, pain that is localized or that radiates to other parts of the body Treatment: Many options, including medication, exercise, physical therapy, massage, acupuncture, education, and surgery

37. Exercises for the Prevention and Management of Low-Back Pain Do low-back exercises at least 3 days per week Emphasize muscular endurance Do not do full range of motion spine exercises early in the morning Engage in regular endurance exercise Be patient and stick with your program