Muscle Performance (part 1)
Muscle (local) fatigue
Acute physiological response that is normal and reversible
How soon does detraining begin?
Detraining begins within 1-2 weeks
Forms of resistance
Manual resistance and mechanical resistance are the two broad methods by which external resistance can be applied A constant or variable load can be imposed through mechanical resistance such as free weights or weight machines Accommodating resistance can be implemented by use of an isokinetic dynamometer that controls the velocity by adjusting the external resistance to meet the internal effort during exercise Body weight or partial body weight is also a source of resistance
What are the physiological adaptions to strength/endurance training in the metabolic system?
Strength and endurance increase ATP, myoglobin, triglyceride, myokinase
Be able to prescribe exercise for strength
Strength: high load/low reps Healthy, untrained adults should train at 40-80% of 1 RM 2-3 sets with 6-12 reps Children, elderly, adults with significant deficit = 30-50% 1 RM
What muscle fiber increases size most readily?
Type IIB
alignment
Patient/client or body segment must be positioned so the direction of movement of a limb or segment of the body replicates the action of the muscle or muscle groups to be strengthened
What type of exercise uses reactive neuromuscular training, performed in return to function stage. Rapid stretch of muscle eccentrically followed by rapid concentric Emphasize speed
Plyometric exercise
Exercise recovery
Recovery from acute exercise, in which the force-producing capacity of muscle returns to 90-95% of pre-exercise capacity, usually takes 3-4 minutes, with the greatest proportion of recovery occurring in the first minute If light exercise is performed during the recovery period (active recovery), recovery occurs more quickly than with total rest (passive recovery)
____ ____: any form of active exercise in which dynamic or static muscle contraction is resisted by an outside force applied manually or mechanically
Resistance exercise
What principle states that adaptive changes are transient unless regularly used functionally or exercise maintained?
Reversibility Principle
This principle refers to the concept that to improve a specific muscle performance element, the resistance program should be matched to that elements constructs.
SAID principle
What type of isometric exercise do you use to improve posture and dynamic stability?
Stabilization exercises
Stabilization
Stabilization refers to holding down a body segment or holding the body steady
What are the physiological adaptions to strength/endurance training in connective tissue?
Strength and endurance increase in tensile strength, bone mineral density
What are the physiological adaptions to strength/endurance training in the neural system?
Strength training → increase motor unit recruitment Endurance training → no changes
What are the physiological adaptions to strength/endurance training in body comp?
Strength training → lean body mass increases for strength training, fat decreases Endurance training → decrease body fat %
What are the physiological adaptions to strength/endurance training in skeletal muscle structure?
Strength training → muscle fiber hypertrophy (greatest in IIb) Endurance training → mitochondria and capillary density
intensity
The amount of external resistance imposed on the contracting muscle during each repetition of an exercise
Mode
The form of exercise, the type of muscle contraction that occurs, and the manner in which the exercise is carried out. Type of muscle contraction forms of resistance position of exercise Energy system Range of movement (long or short arc) application to function
CKC
When a WB position is assumed and the body moves over a fixed distal segment, the term closed-chain exercise is commonly used
____: accelerate body movements, max contraction produces less force than a max eccentric force. Greater number of motor units recruited to control the same load compared with eccentric. Higher metabolic demand
concentric
When does performance in function skills begin to decline?
during the 6th decade of life
____: decelerate body segments, source of shock absorption, advocated during advanced stage of rehab, increased risk for DOMS. Greater gains with max effort than concentric
eccentirc
Anaerobic exercise
high-intensity, low-repetition effort, as muscles rapidly fatigue at near-maximal intensity Østrengthening exercises are categorized as anaerobic
___ ___: dynamic muscle contraction causes joint movement and excursion of a body segment as the muscle contracts and lengthens
isotonic exercise
Aerobic exercise
low-intensity, high-repetition effort over an extended period of time. Øprimarily increases muscular and cardiopulmonary endurance
what type of isometric is a series of exercises where resistance is applied, helps increase strength through ROM. Start in neutral and progress to multi angle?
multiple angle iso
What is ability to perform repetitive sustained activities over a prolonged period of time
muscle endurance
____ ____: work produced by a muscle per unit of time
muscle power
What type of isometric is low intensity, used to decrease pain, spasm, and increase relaxation?
muscle setting
_____ _____: the extent that the contractile elements of muscle produce force
muscle strength
This principle states that if muscle performance is to improve, a resistance load that exceeds the metabolic capacity of the muscle must be applied—that is, the muscle must be challenged to perform at a level greater than that to which it is accustomed.
overload principle
How early do neural adaptations occur?
seen at 4-8 weeks when there is little to no evidence of muscle fiber hypertrophy initial neural responses to resistance exercise are attributed to motor learning and improved coordination through increased recruitment in the number of motor units firing and an increased rate and synchronization of motor unit firing
What are the 3 components of muscle performance?
strength, power, endurance
Cardiopulmonary (General) Fatigue
the systemic, diminished response of an individual to a stimulus as the result of prolonged physical activity, such as walking, jogging, cycling, or repetitive work.
OKC
when a NWB is assumed and the distal segment (foot or hand) moves freely during exercise
List the signs and symptoms of muscle fatigue
- An uncomfortable sensation in the muscle, with pain and cramping possible - Shaking or trembling of the contracting muscle - An unintentional slowing of contraction velocity with successive repetitions of an exercise - Active movements are jerky or inconsistent - Inability to complete the movement pattern through the full range of available motion during dynamic exercise against the same level of resistance - Use of substitute motions—that is, incorrect movement patterns—to complete the activity - Inability to continue low-intensity physical activity - Decline in peak torque during isokinetic testing
What are the benefits of resistance exercise?
- Enhanced muscle performance - Increased strength of connective tissue - Increased bone mineral density and/or less bone demineralization - Decreased joint stress during physical activity - Reduced risk of soft tissue injury - Improved capacity for repair and healing of damaged soft tissues and for tissue remodeling - Improved balance - Enhanced physical performance during daily living, occupational, and recreational activities - Positive changes in body composition - Enhanced feeling of physical well-being - Positive perception of disability and quality of life
stability
-• The ability of the neuromuscular system through synergistic muscle actions to hold a proximal or distal body segment in a stationary position or to control a stable base during superimposed movement. • Joint stability is the maintenance of proper alignment of a joint by means of passive and dynamic components
What are the two main reasons for determining an RM (repetition maximum)?
1) to identify an initial exercise load to be used during exercise for a specified number of repetitions (2) to document a baseline measurement of the dynamic strength of a muscle or muscle group against which exercise-induced improvements in strength can be compared.
What is Rx and Indication for Isometric Exercise?
<60% 1RM, 6-10 sec hold, 10 reps Acute phase of rehab to minimize atrophy, improve neuromuscular control, postural stability
Fatigue Threshold
A patient's threshold for fatigue could be noted as the length of time a contraction is maintained, or the number of repetitions of an exercise that initially can be performed • This sets a baseline from which adaptive changes in physical performance can be measured
Resistance training
An activity in which static or dynamic muscle contraction is resisted by an outside force applied manually or mechanically
Hyperthrophy
Becomes an increasingly important adaptation that accounts for strength gains after extended period of moderate- to high-intensity resistance training, usually by 4-8 weeks, but possibly as early as 2-3 weeks with very high intensity.
What type of exercise utilizes gravity to grade resistance No equipment needed, can be isotonic or isometric, commonly used for HEP Subacute and return to function stages
Calisthenic Exercise
What type of exercise training uses total body conditioning Strength, endurance, flexibility, CV Move through set of rotations then rest for 30-60 seconds (curves, orange theory)
Circuit Training
Coordination
Correct timing and sequencing of muscle firing plus appropriate intensity of muscular contraction
Be able to prescribe exercise for endurance
Endurance: sub max load/low intensity and high reps Isometric contractions for long duration 3-5 sets of 15-25 reps, 40-50% 1RM Can be performed daily
List the factors that can influence the tension generated in skeletal muscle
Energy stores and blood supply Fatigue Age Recovery from exercise Psychological and cognitive factors
What type of stability is applied by therapist or with equipment (belts, plinth, bolster)
External stability
What type of isotonic contraction increases hypertrophy?
Greatest increases in protein synthesis and hypertrophy are associated with high-volume, moderate- resistance exercise performed eccentrically
What factors affect fatigue?
Health status, diet, or lifestyle (sedentary or active), environment all influence fatigue thresholds. In patients with neuromuscular, cardiopulmonary, inflammatory, cancer-related, or psychological disorders, onset of fatigue is often irregular • May occur abruptly, more rapidly, or at predictable intervals
Neuromuscular control
Interaction of the sensory and motor systems that enables synergists, agonists, and antagonists, as well as stabilizers and neutralizers, to anticipate or respond to proprioceptive and kinesthetic information
What type of stability is isometric contraction of an adjacent muscle group?
Internal stability
____ ____: velocity of limb held constant by a device, type of dynamic exercise, requires max effort while keeping speed constant
Isokinetic Exercise
What exercise is there a contraction in which muscle length remains constant against an immovable resistance (manual holding, holding weight/against gravity)
Isometric Exercise
What is the capacity of a muscle to do work, influenced by all body systems?
Muscle performance
Does pain correlate with tissue damage?
No pain is subjective