Transcript KNR 240 Chapter 5 Muscular Health - KNR240

chapter
5
Assessment
of Muscular Fitness
Resistance Training
• Requires the body to move against an opposing forceusually some type of equipment.
• Muscular Strength – maximal amount of force a muscle
or group of muscles can generate in a single maximal
contraction or with a single maximal effort.
• Muscular Endurance – capacity to exert repetitive
muscular force or the ability of the muscle to remain
contracted or contract repeatedly for long periods of
time.
ACSM Guidelines
• Resistance training should be progressive,
individualized, and provide a stimulus to all the major
muscle groups.
• One set 8-10 exercises for major muscle groups
• 2 days/week minimum
• 3-20 repetitions to fatigue (RPE 19-20)
• Example: chest press, shoulder press, tricep extension,
bicep curl, lat pull-down, lower back extension, ab
crunch, leg extension, leg curl, calf raise
Health Benefits
of Muscular Fitness
Preservation of, or enhanced, fat-free
mass and resting metabolic rate
Preservation of, or enhanced, bone mass
with aging
Improved glucose tolerance and insulin
sensitivity
Reduced heart rate and blood pressure
response while lifting any submaximal
load (which reduces myocardial oxygen
demand during activities requiring
muscular force)
(continued)
Health Benefits
of Muscular Fitness (continued)
Lowered risk of musculoskeletal injury,
including low back pain
Improved ability to carry out activities of
daily living in old age
Improved balance and decreased risk of
falls in old age
Improved self-esteem
Athletic Performance
Aspects of Muscular Fitness
Enhanced muscular strength and
muscular endurance
Enhanced speed, power, agility, and
balance
Reduced risk for musculoskeletal injuries
(continued)
Athletic Performance
Aspects of Muscular Fitness
(continued)
Improved body composition for various
events or activities
Improved confidence for performing
certain athletic activities involving high
levels of muscular fitness
Enhanced performance in most athletic
activities
Training Principles/Terms
• Specificity – training in a specific way for a specific
result or change
• Overload – a training stress or intensity greater than
what a client is use to in order to see continual
physiological adaptations
• Progression – as the training status improves over
time, training stress or intensity continues to
increase
• Hypertrophy – Increase in the size of the muscle
fiber.
• Atrophy – A reduction of muscle size due to
detraining or age.
Muscle Facts
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Everything is driven by muscles.
Muscle is more dense than fat.
Fat takes up 28% more volume than muscle.
Muscle is wet. Fat is dry.
Most people gain 5-5 ½ lbs of muscle over 16 weeks
of training.
• 5 lb. increase in muscle = 50 kcal increase/day of
RMR
Muscle Facts
• After age 30, people start to lose muscle mass.
• With aging, motor nerves (nerves that turn on
muscle fibers) become disconnected from individual
muscle fibers.
• Estimated by age 70, 15% of the motor nerves
become disconnected from their fibers.
• By age 75, about 25% of men and 75% of women
can NOT lift more than 10 lbs.
Types of Muscle Actions
• Concentric – Shortening of the muscle occurs.
Positive phase.
• Eccentric – Lengthening of the muscle occurs.
Negative phase.
• Isometric – Muscle is activated and develops force,
but no movement occurs.
– It is joint-angle specific. Increase in muscle fiber
recruitment at the trained angle.
– Goal to increase strength at the weakest point.
Helps with sticking joints.
– Used in rehab/physical therapy.
Isotonic Training
• Most Common-referred to as weight training with
free weights or machines.
• Advantages:
– May be most beneficial to overall health –
strength, tone, endurance.
– Improved tendon and ligament strength
– Less risk of injury
– Decreased incidence of arthritis and low back
pain
– Improved bone strength, energy and fat loss.
FITT Principle for Strength Training
Terms
• Repetition – One complete movement of an exercise
• Set – Group of repetitions
• Repetition Max (RM)-Maximal number of reps per set that can
be performed with proper lifting technique using a given
resistence.
• 1RM – Heaviest resistance that can be used for 1 complete
repetition of an exercise. (Prediction chart on page 102)
• Intensity – Amount of weight lifted on a particular set.
– Can increase intensity by: increasing wt., reps, sets or
decreasing rest time
Common Muscular Strength
Assessments
• Handgrip Test
– See procedures on p. 80 ACSM
– Norms are provided on p. 79, Table 5-1.
Procedures for 1RM Testing
1. The subject performs a light warm-up of 5
to 10 repetitions at 40 to 60% of
perceived maximum (i.e., “light” to
“moderate” effort).
2. Following a 1-min rest with light
stretching, the subject performs 3 to 5
repetitions at 60 to 80% of perceived
maximum (i.e., “moderate” to “hard”
effort).
(continued)
Procedures for 1RM Testing
(continued)
3. The subject attempts a 1RM lift. If the lift
is successful, a rest of 3 to 5 min is taken.
The goal is to find the 1RM within 3 to 5
maximal efforts.
4. The 1RM is reported as the weight of the
last successfully completed lift.
Push-Up Test
1. Explain the purpose of the test to the
client.
2. Inform client of proper breathing
technique (i.e., exhale when pushing
away from the floor).
(continued)
Push-Up Test (continued)
3. For male clients: Standard “up” position,
with hands shoulder-width apart, back
straight, head up, using the toes as the
pivotal point.
4. For female clients: Modified “knee pushup” position, with legs together, lower
legs in contact with mat with ankles
plantar flexed, back straight, hands
shoulder-width apart, head up.
Note: Some males need to use modified
position, and some females can use fullbody position.
(continued)
Push-Up Test (continued)
5. The subject must lower the body until the
chin touches the mat. The abdomen
should not touch the mat.
6. The subject’s back must be straight at all
times, and the subject must push up to a
straight-arm position.
7. Demonstrate the test, and allow the client
to practice if desired.
(continued)
Push-Up Test (continued)
8. Remind the client that brief rest is allowed
only in the up position.
9. Begin the test when the client is ready,
and count the total number of push-ups
that the client completes before reaching
exhaustion.
10. The client’s score is the total number of
push-ups performed.
11. Percentiles can be found on p. 87 ACSM.
Curl-Up Test
1. Explain the purpose of the test to the
client.
2. Inform the client of proper breathing
technique (exhale when curling up from
the floor).
3. Individual assumes a supine position on a
mat with the knees bent 90°.
4. The arms are at the sides, with fingers
touching a piece of masking tape.
(continued)
Curl-Up Test (continued)
5. A second piece of masking tape is placed
10 cm apart.
6. A metronome is set to 50 beats/min and
the individual does slow, controlled curlups to lift the shoulder blades off the mat
(trunk makes a 30° angle with the mat) in
time with the metronome (25 curl-ups/
min). The low back should be flattened
before curling up. The test is done for 1
minute.
(continued)
Curl-Up Test (continued)
7. Demonstrate the test, and allow the client
to practice if desired.
8. Percentiles by age groups and
gender can be found on p. 88 ACSM
Special Considerations:
Older Adults
Senior Fitness Test (SFT)
Assess the key physiological parameters
(i.e., strength, endurance, agility, and
balance) needed to perform common
everyday physical activities that often
become difficult for older individuals.
Two specific tests included in the SFT, the
30-s chair stand and the single arm curl,
can be used to assess muscular strength
and endurance in most older adults safely
and effectively.
The 30-Second
Chair Stand Test
Indication of lower body strength.
Count the number of times within 30 s that
an individual can rise to a full stand from
a seated position without pushing off with
the arms.
Single Arm Curl Test
Indication of upper body function that is
important in executing many normal
everyday activities.
Involves determining the number of times
a dumbbell (5 lb, or 2.3 kg, for women;
8 lb, or 3.6 kg, for men) can be curled
through a full range of motion in 30 s.
FLEXIBILITY
• Flexibility – Defined as the range of motion (ROM) of a
single joint or a group of joints. It is specific to each joint. The
amount of movement is largely determined by the tightness of
muscles, tendons, and ligaments that are attached to the joint.
• Benefits:
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Reduce muscle soreness
Reduce muscle tension
Reduce risk of low back pain
Improve muscle performance
Improve posture
Improve muscle coordination
Reduce the risk of injury
Types of Flexibility
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Active (Dynamic) Flexibility – “The degree to which the force of a muscle
contraction can move a joint.” A muscle is stretched by a contraction of the
opposing muscle. Involves movement. Dynamic shoulder flexibility would affect
your ability to swing a golf club. Important for daily activities and sports.
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Passive (Static) Flexibility – Refers to the ability to assume and maintain an
extended position at one end or point in a joint’s range of motion. It involves no
muscle contraction. An outside force or resistance provided by yourself, a
partner, gravity or a weight helps the joints move through their ROM. Easier to
measure than dynamic flexibility and is usually how we refer to flexibility.
FITT PRINCIPLES
• FREQUENCY – minimum of 2-3 days/week; 5-7 days/week
may be better.
• INTENSITY – Slowly stretch warm muscles to the point of
slight tension or mild discomfort.
• TIME – Hold the stretch for 10-30 seconds; repeating 3- 5
times. Relax and breath.
• TYPE – Stretch the major muscle groups exercised. Refer to
the end of the chapter for exercises.
Flexibility Testing
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Flexibility of one joint does not necessarily indicate flexibility
of other joints. There is no general flexibility test for the whole
body.
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Sit and Reach test
• Used by almost all health related physical fitness
testing batteries.
• Used extensively because it has been noted that
people with low back problems often have a restricted
ROM in the hamstrings and lower back.
• See pg. 95 ACSM for Canadian Trunk Forward Flexion
test procedures and norms.
The Lower Back
• Low Back Pain has a direct relationship to lifestyle and wellness
behaviors. Proper lifestyle choices can help prevent LBP.
Sedentary lifestyles contribute to loss of muscular strength,
endurance, and a limited ROM.
• Low Back Pain is the number one physical complaint by
individuals ages 25-60 in the U.S. Second most common
ailment for job absenteeism for ages 30-60. It contributes for
25% of days lost for the entire work force.
• LBP will affect 60-80% of the American and European
population at some point.
• $50 billion will be spent each year by government and industry
for LBP (job absenteeism, disability payments, worker’s
compensations, disability insurance, medical and legal fees)
• Most pain occurs in the lumbar (lower) and sacral region
because it bears the majority of your weight.
Causes of LBP
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The most common cause of LBP
is physical inactivity!
Poor posture
Faulty body mechanics
Stressful living and working habits
Weak musculature – especially
the abs
Poor flexibility in the lower back
and hamstrings
Smoking
Prevention of LBP
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Exercise regularly to strengthen
your back and abdominal
muscles.
Lose weight, if necessary, to
lessen strain on your back.
Avoid smoking (which increases
degenerative changes in the
spine).
Lift by bending at your knees,
rather than the waist, using leg
muscles to do most of the work.
Receive objects from others or
platforms near to your body, and
avoid twisting or bending at the
waist while handling or
transferring it.
Prevention of LBP
• Avoid sitting, standing, or working in any one position for too long
• Maintain a correct posture (sit with your shoulders back and feet flat on
the floor, or on a footstool or chair rung. Stand with head and chest
high, neck straight, stomach and buttocks held in, and pelvis forward).
• Use a comfortable, supportive seat while driving.
• Use a firm mattress, and sleep on your side with knees drawn up or on
your back with a pillow under bent knees.
• Try to reduce emotional stress that causes muscle tension.
• Be thoroughly warmed-up before engaging in vigorous exercise or
sports.
• Undergo a gradual progression when attempting to improve strength or
athletic ability.
Treatment of Low Back Pain
• Physical Activity – Only 1% of all back patients need
surgery. Most rehabilitation and prevention is
lifestyle related.
• Maintain a normal weight. Excess abdominal weight
can lead to lordosis and poor posture.
• Participate in regular aerobic exercise.
• Participate in regular muscular strength and
endurance activities, especially for the abdominal
and back regions.
• Incorporate lower back and hamstring flexibility
exercises. Work all the planes of motion.
Tip of the Day
• Results in training occur with
consistency and effort – a lifestyle
habit!