07-05: Resistance Exercise for Impaired Muscle Performance Flashcards
Three elements of muscle performance
- Strength
- Power
- Endurance
Strength
- Force
- Force x Distance = Work
- Greatest measurable force that can be exerted by a single muscle to overcome resistance during a single maximum effort
- Withstands resistance of muscles
Functional Strength
- Neuromuscular system’s ability to produce and control forces during functional activities
Power
- Force x distance/time
- Work over time - can be brief or over extended periods of time
- Burst
Endurance
- Repetitive or sustained activities over a prolonger period of time
- Walking, cycling, swimming
Muscle Endurance
- Ability to contact repeatedly against load and resist against fatigue over an extended period of time
Resistance Exercise
- Active exercise in which dynamic or static muscle contraction is resisted by an outside force (manual - PT/PTA - or mechanical - machine)
- Also resistance training
Muscle types of resistance exercise
- Type 1 (Tonic): Slow twitch, postural muscles
- Type 2 (Phasic): Fast twitch, burst of energy, quick fatigue
Overload Principle
- Muscle must be challenged to perform at a greater level than its usual
SAID Principle
- Specific Adaptation to Imposed Demand
- Extension of Wolff’s law
- Specificity of training: Anticipate function and incorporate into training
Reversibility Principle
- Use it or lose it
- Gains in performace reduce 1-2 weeks following cessation of exercise
- Increases in performance must be incorporated into functional activities to maintain
Skeletal muscle function and adaptation to resistance exercise
- Factors that influence tension generation: blood, fatigue
- Recovery from fatigue: 3-4 minutes
- S/S of fatigue: pain and cramping, tremors, jerky motions, incomplete ROM, substitutions, unable to finish movement
Physiologic Adaptations to Resistance Exercise
- Depends on patient
- Neural adaptations
- Hypertrophy
- Hyperplasia
- Fiber type adaptations
Neural adaptations
- Increased recruitment of motor units
- Increased rate and synchronization of firing - strength increases with no evidence of hypertrophy
Hypertrophy
- Increase in size of myofibrils
- 4-8 weeks of high intensity training
- Greatest gain with high-volume moderate resistance eccentric training
Hyperplasia
- Fiber splitting (Longitudinal sploit
- Increase number of muscle fibers
Fiber Type Adaptation
- Type I (Tonic) to Type II (Phasic), as seen in SCI pts
- Primarily for movement: slow to fast
Determinants (Parameters) of Resistance Exercise
- Alignment and stabilization
- Intensity
- Volume
- Exercise Order
- Frequency
- Duration
- Rest Interval (recovery period)
- Mode of exercise
- Velocity of exercise
- Integration of Function
Alignment and Stabilization
- Alignment: Direction of muscle fibers, line of pull
- Stabilization (External): Hand on patient, stabilize proximal
- Stabilization (Internal): Isometric contraction of Agonist group
Intensity
- The amount of resistance used
- Should never cause pain
- Submaxima: Early stages of healing, goal is for endurance, after immobilization
- Maximal loading: Increase mm size and strength
Volume
- Total number of sets and reps
- Reps: Goal is strength or endurance
- Sets: Single - early phases, Multiple - Advanced programs
Exercise Order
- Exercise large muscle groups before smaller groups, multijoint muscles before single joint muscles
- Warm up before exercises, intensity is pt-specific
Frequency
- No optimal frequency
- Low load can be performed daily, several times daily (HEP isometrics)
- Higher loads require more recovery time, usually every other day
Duration
- 2-3 weeks for neural adaptation
- 6-12 weeks for hypertrophy and true strength gains
Rest Interval (Recovery Period)
- 2-3 minutes after moderate training
- 4-5 minutes for high-intensity training
- Active recovery more efficient than passive recovery; light ex better to reduce fatigue
Mode of exercise
- Isometric, Isotonic, Isokinetic, OKC, CKC, manual resistance, mechanical resistance, body weight, short arc, long arc
Velocity of exercise
- Increase in velocity eccentric contraction = increased force production
- Increase in velocity concentric contraction = decreased force production
Integration of function
- Requires balance, strength and task-specific training
Types of Resistance Exercise
- Manual and Mechanical Resistance
- Isometric Exercise (Static Exercise)
- Dynamic Exercise (Concentric/Eccentric)
- Dynamic Exercise (Constant/Variable resistance
- Isokinetic Exercise
- Open Chain and Closed Chain Exercise
Manual/Mechanical Resistance
- Manual: Resistance needs to be controlled; cannot be quantified
- Mechanical: Can be quantified to varying degrees
Isometric Exercises
- Loss of static muscle strength from 8%/week to as much as 5%/day with immobilization
- Three types of isometric exercises
- Muscle Setting: Prevents atrophy
- Stabilization: Increases strength and function
- Multi-angle stabilization: Precursor to stabilization or functional activities
Dynamic Exercise (Concentric/Eccentric)
- Plyometrics
- Picking up objects
- Eccentric weakness associated with tendonopathies; also greater DOMS
Dynamic Exercise (Constant/Variable)
- Constant = free weights, pulley systems, machines
- Variable = manual resistance, elastic products, designed machines and isokinetic macthines
Isokinetic Exercise
- Used sparsely
- Later phases of rehab
OKC/CKC
- CKC = distal
- Determined by task specific training
- Effective in increasing strength and endurance
Precautions for resistance exercise
- Valsalva Maneuver
- Substitute motions
- Overtraining
- Overwork
- Exercise-induced muscle soreness
- Pathologic fracture
Valsalva Maneuver
- Closing of the epiglottis
- Deep inspiration, increase in BP
Overtraining
- Decreased strength due to inadequate rest/recovery; reversible
Overwork
- Weakness
- Decreased strength in nonprogressive neuromuscular diseases such as Guillan Barre or post polio
- Requires longer recovery time
Exercise-Induced Muscle soreness
- NO known cause
- Prevent with stretching
- Treat with modalities (massage, light exercise)
- Soreness may occur within 24-48 hours, subsides within 3-4 days, can last 10 days
Pathologic fracture
- Osteopenia or Osteoporosis
Manual Resistance
- Form of active resisted exercise where resistive force is applied by PT/PTA to either static or dynamic muscular contraction
- Stabilize body parts; consider gravity
Types of Resistance Training
- PRE
- Circuit Training
- Plyometric training
- Isokinetic regimens
