Lecture 11 Flashcards
Drop by ____ in muscle force from age _____?
25% and 40-65 y/o
Change in muscle strength with age: Aging process (5)
- Motor neurons die off
- Muscle fiber die
- Reinnervation of a few fibers by neighboring type I motor neurons
- Increase size of rescuing motor units
- Change in type I vs type II ratio
Structural changes in the neuromuscular junction (5)
- Flattering of cell membrane containing the receptors
- Increase the distance between receptors and decrease quality of transmission
- Myelin sheath infiltration
- can migrate to synaptic cleft and partly block acetylcholine which decrease signal transmission
- Decrease speed and strength of muscle contraction
health related benefits of RT (6)
Is resistance training as effective as aerobic training to reduce BP and insulin resistance in OA ?
Body composition: Increase lean tissue mass + metabolic rate + daily energy expenditure = result in decrease body fat up to 9%
BP: Small decrease in resting SBP and DBP = decrease risk of stroke & CAD
Bone mass: Improve bone health = reduce risk of osteoporosis
Glucose tolerence: Improvement in glucose tolerence & insulin resistance
Lower back pain: Increased strength of vertebral muscle = maintain muscular balance = decrease low back pain
Blood lipids: Lowering total cholesterol & triglyceride levels
NO
What is the overload principle ? (4)
The capacity of the muscle cell to exert force increase and decrease relative to the demands placed on the muscular system.
- OA live sedentary lifestyle
- Demands on muscle decrease
- Muscle cells decrease in size (atrophy)
- Muscles strength decrease + mechanical force
Fixed-weight machines: (3)+ and (2)-
+
- can target the larger muscle groups more efficiently because the body is pretty stable
- Easier for proper mvt technique
- Low risk of injury
-
- Minimal resistance can be too great for frail OA
- Increments in resistance can be too large for frail OA
Resistance bands: benefits (6)
- More convenient vs machines
- Allow for endless variation of exercises
- Takes some skills to learn proper technique
- Functional mvt patterns that mimic both everyday activities ans sport specific activities
- Easier for mvt initiation
- Lower risk of injury
Free- weight (4)
- More convenient vs machines
- Allow for endless variation of exercises
- Takes some skills to learn proper technique
- Functional mvt patterns that mimic both everyday activities ans sport specific activities
How to select exercises ? (4)
- Stress all major muscle groups for maintaining muscular balance
- Single joint exercises
- Multiple-joint exercises
- Should incorporate both types of exercises for maximal effect
Resistance (3) + (3)
- Also know as load
- Amount of force exerted against working muscles
- Expressed in absolute (lbs or kg) or relative (% or max force)
- more or equal to 90% of 1RM = heavy
- 70-90% 1RM = mod
- less than 70% 1RM = light
What is the proper load for OA
- Beginning lifting
- Frail OA
- Healthy OA
- 45 to 50% of 1RM needed to increase dynamic muscular strength
- Can tolerate loads up to 80% 1RM
- 80% 1 RM recommended to stimulate muscle cell hypertrophy and strength development
Study High RT vs variable RT
HR = 80% 1RM VR = 80%, 65%, 50% 1RM
- 6months (1RM measured every 25 days)
- men and women over 60 y/o
- DAT = walking, climbing stairs, walking while carrying a weight
- HR and VR increase in strength and fat free mass
- VR decrease difficulty in performing the carry task vs HR
What should be a priority in a training program for OA ? why?
Optimal stimulation of the large muscle groups in legs and the upper body
To increase the health benefits (body comp, BP, Bone mass, Glucose tolerance, blood lipids) and performance benefits (walking endurance)
Should we always exercises larger muscle first ? why ?
What is the appropriate sets for OA? why ?
What to avoid ?
yes, to allow increase in intensity and decrease muscle fatigue in large muscle group exercises.
Not exceed 2-3 sets, because the highest bp and HR occur in the last few reps of a set.
Avoid set to failure in OA
What is the load ans reps recommended for OA ?
60 to 80% 1RM - 8-10 reps (strength)
40 to 60% - 6-10 reps (power)
less than 65% - 12-15 reps (endurance)
