Week 9 - Resistance Training Flashcards
(55 cards)
What is the percentage of decrease of peak muscle force from age 40-65?
25%, so about 1% per year
What is the aging process related to muscle fibers.
- Motor neurons die
- Muscle fibers die
- Reinnervation of a few fibers by neighbouring Type 1 motor neurons
- Increase size of rescuing motor units
- Change in Type 1 vs Type 2 ratio
What are the structural changes in the neuromuscular junction?
- Flattening of cell membrane –> increases the distance between the receptors and decreases the quality of transmission
- Myelin sheath infiltration –> can migrate to synaptic cleft and partly block acetylcholine which decrease signal transmission
What are the consequences of structural changes in the neuromuscular junction?
decreases speed and strength of muscle contraction
What are the health-related benefits of resistance training?
- body composition: increase lean tissue mass + metabolic rate + daily expenditure –> decrease body fat of up to 9%
- blood pressure: small decrease in resting systolic and diastolic BP –> decrease risk of stroke and coronary artery disease
- bone mass: improves bone health –> reduces risk of osteoporosis
- glucose tolerance: improvements in glucose tolerance and insulin resistance
- lower back pain: increased strength of vertebral muscles = maintain muscular balance = lower back pain
- blood lipids: lowering total cholesterol and triglyceride levels
A reduction of only ___ mmHg in SBP and DBP lower stroke risk by 14 and 17% respectively, and the risk of coronary artery disease by 9% and 6%, respectively.
2 mmHg
Is resistance training as effective as aerobic training to decrease blood pressure and insulin resistance in OA?
No!
Aerobic = 3-5 mmHg
RT = 2-3 mmHg
What was the goal of the pioneer study (1990)?
to determine the feasibility and physiological effects of high RT in frail OA (10 subjects)
What was the target population and range of age?
Mean 90+
Range 86-96
How many had a history of falls and how many used ambulatory assistive devices?
- Falls: 8
- Assistive devices: 7
What were the exercise parameters? (duration, frequency, intensity)
- Duration: 8 weeks
- Frequency: 3/week
- Intensity: 50-80% of 1 RM
Which muscles were they targeting, and how? What were the safety measures involved?
Progressive RT: knee extensors + flexors
- 3 sets of 8 reps (total of 24 reps)
- concentric + eccentric contractions
- week 1: load = 50% 1RM (1RM remeasured every 2 weeks)
- week 2-8: load = 80%
Safety: monitoring of HR and BP (ensure little variation during training): less than 10 mmHg systolic BP and less than 5 mmHg for HR
What were the results of the experiment with regards to completion, attendance and physical parameters?
- 9/10 completed program
- Attendance 98.9%
Improvement in physical parameters:
- knee extensors strength increased by 174%
- mid thigh muscle area increased by 9%
What were the results of the experiment with regards to functional level?
Improvement in functional level:
- no change in habitual gait speed but 48% improvement in tandem gait speed
- 2 subjects no longer used canes at the end
- 1/3 subjects who could not initially rise from a chair without use of the arms became able to do so
What is the overload principle in OA?
Capacity of the muscle cells to exert force increases and decreases relative to the demands placed on the muscular system
What happens to OA who live sedentary lifestyles?
sedentary lifestyle –> demands on muscles decreases –> muscle cells decreases in size (atrophy) –> muscles decreases in strength and mechanical force
What are the 3 types of resistance training?
fixed-weight machines, free weights, resistance bands
What are some characteristics and considerations when creating a resistance training (RT) program?
safe, effective, convenient, enjoyable (adherence)
What are the advantages of fixed-weight machines?
- can target the larger muscle groups more efficiently because the body is pretty stable
- easier for proper movement technique (speed and quality)
- low risk of injury (if load is right)
What are the disadvantages of fixed-weight machines?
- minimal resistance can be too great for frail OA
- increments in resistance can be too large for frail OA
What is the main difference between seated and standing cable pulley machines?
Standing allows for the use of postural muscles to be much more involved = closer to ADLs
What are the benefits of free weights?
- more convenient vs machines (i.e. practicality)
- allow for endless variation of exercises
- takes some skill to learn proper technique
- functional movement patterns that mimic both everyday activities and sport-specific activities
What are the benefits of resistance band?
- more convenient vs mschines (i.e. practicality)
- allow for endless variation of exercises
- takes some skill to learn proper technique
- functional movement patterns that mimic both everyday activities and sport-specific activities
- easier for movement initiation
- lower risk of injury
How to select exercises?
Stress all major muscle groups so that muscular balance can be maintained.
Should incorporate both single-joint and multiple-joint exercises for maximal effect.
