Resistance Exercise For Impaired Muscle Performance PDF

Resistance Exercise For Impaired Muscle Performance BY: Dr: Mohamed Naeem  Definition Muscle performance - capacity of a muscle to do work An essential element of rehabilitation programs for persons with impaired function. The key elem...

Resistance Exercise For Impaired Muscle Performance BY: Dr: Mohamed Naeem  Definition Muscle performance - capacity of a muscle to do work An essential element of rehabilitation programs for persons with impaired function. The key elements of muscle performance are (strength, power, and endurance) - Resisted exercise: Any form of active exercise in which dynamic or static muscle contraction is resisted by an outside force applied manually or mechanically. Also referred to as resistance training.  Potential Benefits of Resistance Exercise Enhanced muscle performance Increased strength of connective tissues Greater bone mineral density or less bone demineralization Decreased stress on joints during physical activity Reduced risk of soft tissue injury during physical activity Repair and heal damaged soft tissues due to positive impact on tissue remodeling.  Possible improvement in balance Enhanced physical performance during daily living, occupational, and recreational activities Positive changes in body composition: ↑ lean muscle mass or ↓ body fat Enhanced feeling of physical well-being  Muscle strength The ability of contractile tissue to produce tension and a resultant force based on the demands placed on the muscle The greatest measurable force that can be exerted by a muscle or muscle group to overcome resistance during a single maximum effort Functional strength The ability of the neuromuscular system to produce, reduce, or control forces, imposed, during functional activities, in a smooth, coordinated manner.  Muscle Power - Definition: the rate of performing work. the work (force × distance) produced by a muscle per unit of time (force × distance/time). related to the strength and speed of movement Power training: The greater the intensity of the exercise and the shorter the time period taken to generate force, the greater is the muscle power  Muscle Endurance Definition: The ability to perform low-intensity, repetitive or sustained activities over a prolonged period of time - Cardiopulmonary endurance (total body endurance) - Muscle endurance (Local endurance): muscle contract and lift or lower a light load for many repetitions or sustain a muscle contraction for an extended period of time - Endurance training: Low-intensity muscle contractions, a large number of repetitions, and a prolonged time period  Principle of Exercise 1) Over Load principle Muscle performance will improve, a load that exceeds the metabolic capacity of the muscle must be applied, The muscle must be challenged to perform at a level greater than that to which it is accustomed. Application of over load: In a strength training program: intensity & repetitions In endurance training program: intensity & repetitions  2) SAID The SAID principle (specific adaptation to imposed demands) this principle applies to all body systems and is an extension of Wolff’s law (body systems adapt over time to the stresses placed on them). 3) Reversibility Principle Adaptive changes in the body’s systems, such as increased strength or endurance, in response to a resistance exercise program are transient unless an individual participates in a maintenance program of resistance exercises.  Factors that Influence Tension generation in Normal Skeletal Muscle 1) Cross-section and size of the muscle. 2) Fiber arrangement and fiber length. 3) Length-tension relationship of muscle 4) Recruitment of motor units 5) Type of muscle contraction Eccentric> isometric > concentric 6) Type of muscle fiber  Fatigue Muscle (local) fatigue: the diminished response of muscle to a repeated stimulus. This occurs during exercise when a muscle repeatedly contracts statically or dynamically against an imposed load. Causes of fatigue Decrease in energy stores, insufficient oxygen and a build-up of H¯ Inhibitory (protective) influences from the central nervous system decrease in the conduction of impulses at the myoneural junction, particularly in fast- twitch fibers Cardiopulmonary (general) fatigue. This type of fatigue is the diminished response of an individual (the entire body) as the result of prolonged physical activity, such as walking, jogging, cycling, or repetitive lifting. Causes of general fatigue Decrease in blood sugar (glucose) levels Decrease in glycogen stores in muscle and liver Depletion of potassium, especially in the elderly patient  Signs and Symptoms of Muscle Fatigue 1) An uncomfortable sensation in the muscle, even pain and cramping 2) Tremor in the contracting muscle 3) Active movements jerky, not smooth 4) Inability to complete the movement pattern through the full range of available 5) motion during dynamic exercise against the same level of resistance 6) Use of substitute motions to complete the movement pattern 7) Inability to continue low-intensity physical activity  Adaptations of resistance exercise 1) Skeletal Muscle Adaptations: Hypertrophy: 2-3 weeks Hyperplasia: It's an increase in the number of muscle fibers. As result of longitudinal splitting of fibers.  II) Neural adaptation: Starts within 4- 8 weeks of regular training. It's due to Decrease in the inhibitory function of the CNS Decrease in GTO sensitivity Increase number of motor unit recruitment Increase rate of firing & Synchronize firing III) Bone: Minimizes or prevents loss of bone mineral density. Can be used for the treatment of osteoporosis. IV) VASCULAR & METABOLIC ADAPTATIONS Decreased capillary bed density Decreased mitochondrial density ATP & CP storage increase Myoglobin storage increases CPK & Myokinease increase V) Connective tissue: strong ligaments and tendons may be less prone to injury.  DETERMINANTS OF RESISTANCE EXERCISE 1) Alignment Alignment and muscle action & Alignment and against gravity 2) Stabilization: External: by therapist or patient’s hand or by equipment such as belt or straps. Internal: is achieved by an isometric contraction of an adjacent muscle group that does not enter into the movement pattern.  3) Intensity The intensity of exercise in a resistance training program is the amount of resistance (weight) imposed on the contracting muscle during each repetition of an exercise. Sub maximal loading. Exercise at moderate to low intensities is indicated: At the beginning of an exercise program to evaluate the patient’s response. In the early stages of soft tissue healing when injured tissues must be protected After periods of immobilization ,increasing the risk of pathological fracture For most children or older adults When the goal of exercise is to improve muscle endurance  To warm up and cool down prior to and after a session of exercise Near maximal or maximal loading. High-intensity exercise is indicated: When the goal of exercise is to increase muscle strength and power and possibly increase muscle size. For healthy adults in the advanced phase of a rehabilitation program after a musculoskeletal injury in preparation for returning to high occupational or recreational activities In a conditioning program for individuals with no known pathology For individuals training for competitive weight lifting or body building  Repetition Maximum -It is defined as the greatest amount of weight (load) a muscle can move through the available range of motion (ROM) a specific number of times. -This term was first reported by DeLorme, 1) to document a baseline measurement of the dynamic strength of a muscle or muscle group 2) to identify an exercise load (amount of weight) to be used during exercise for a specified number of repetitions. Training zone: Low exercise: 30-40 % of 1RM as used for sedentary person, elderly and children Moderate exercise: 50- 60% of 1RM as used for untrained person Sub maximal exercise: 75- 90 % of 1RM as used for highly trained person.  4) Volume Repetitions: The number of repetitions in a dynamic exercise program. At Low intensity exercise intensity about 15 repetitions are possible, at Moderate intensity exercise about 10 repetitions. at High intensity exercise as 4 or 5 repetitions. Sets: A number of repetitions grouped together is known as a set or bout. After each set of a specified number of repetitions.  5) Exercise order large muscle groups should be exercised before small muscle groups and multi-joint muscles before single-joint muscles. 6) Frequency - Frequency refers to the number of exercise sessions per day or per week. - The greater the intensity and volume of exercise, the more time is needed. - children and the very elderly frequency is two to three sessions per week. - Highly trained athletes train at a high intensity and volume up to 6 days per week. 7) Duration at least 6 to 12 weeks of resistance training is required. 8) Rest Interval (Recovery Period) A shorter rest interval is adequate after low-intensity exercise. Moderate-intensity resistance training, a 2- to 3-minute. High-intensity resistance training rest intervals (4 to 5 minutes) 9) Mode of exercise: Type of Muscle Contraction: isometric or dynamic ( eccentric or concentric) Position for Exercise: non-weight-bearing or weight-bearing positions. 10) Velocity of Exercise - Concentric Muscle Contraction: As the velocity of muscle shortening increases, the force the muscle decreases. - During an eccentric contraction: as the velocity of active muscle lengthening increases, force production in the muscle initially also increases.  Manual and mechanical resistance Types of mechanical resistance 1. weights: Sandbags/ metal weights etc are used. advantage: Less equipment- convenient for home Resistance can be measured and altered easily Easy to understand and perform Disadvantage: Resistance always works vertically, in the direction of gravity.  Static exercise Indications: 1. To prevent atrophy when joint movement. Is not possible 2. To activate muscles without disturbing healing tissues 3. To develop postural/ joint stability 4. To develop isometric muscle strength 5. To improve muscle strength when dynamic strengthening is painful Types of static exercise 1. Setting exercise: Low intensity isometric with very low or no resistance. 2. Multiple angle isometrics  PRECAUTIONS FOR RESISTANCE EXERCISE - Keep the temperature of the room comfortable for vigorous exercise. - Caution the patient that pain should not occur during exercise. - Do not initiate resistance training at a maximal level of resistance, to avoid (DOMS). -Avoid use of heavy resistance during exercise for children, older adults and patients with osteoporosis. - Do not apply resistance across an unstable joint or distal to a fracture site that is not completely healed. - Avoid breath-holding during resisted exercises to prevent the Valsalva maneuver. - Avoid exercises that place excessive, unintended secondary stress on the back. - Discontinue (stop) exercises if the patient experiences pain, dizziness. - Substitute movement & Overwork - Exercise induced muscle soreness: Acute muscle soreness develops during or directly after strenuous exercise performed to the point of muscle exhaustion. THANKS