Transcript Chapter Four

Muscular Strength and
Endurance
Chapter Four
Pgs. 97 - 140
Mrs. Wheeler / Mr. Rath
© 2013 McGraw-Hill Higher Education. All rights reserved.
Muscular Strength and Endurance
pg. 98
Muscles make up more than 40% of your
body mass
Well-developed muscles can assist with:
Daily routines
Protection from injury
Enhancement of your overall well-being
Muscular strength is the amount of force a
muscle can produce with a single
maximum effort
Muscular endurance is the ability to resist
fatigue while holding or repeating a
muscular contraction
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Basic Muscle Physiology
pg. 98
Muscles consist of individual muscle fibers
(cells) connected in bundles
Muscle fibers are made up of smaller
protein structures called myofibrils
Myofibrils are comprised of contractile
units called sarcomeres (actin and myosin)
Proper strength training causes individual
fibers to increase the number of myofibrils
resulting in hypertrophy
Inactivity can reverse this process
resulting in atrophy
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Basic Muscle Physiology
pg. 98 / T4-4
Hypertrophy is the development of large
muscle fibers
Atrophy is the reduction of the size of the
muscle fiber due to inactivity or injury
Hyperplasia is the increase in the number
of muscle fibers. It is not thought that
hyperplasia plays a significant role in
muscle size in humans.
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Skeletal Muscle Tissue
pg. 98
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Basic Muscle Physiology
pg. 98 - 99
Slow-twitch (Type I) fibers are:
Fatigue resistant
Don’t contract as rapidly and forcefully as fasttwitch fibers
Rely primarily on the Oxidative Energy System
Intermediate (Type II A) fibers: Intermediate in twitch
velocity and oxidative capacity.
Fast-twitch (Type IIB) fibers:
Contract rapidly and forcefully
Fatigue more quickly than slow-twitch fibers
Rely more on the Phosphagen and Nonoxidative
Energy Systems
Strength Training can increase the size and strength of
both fibers types, although fast-twitch fibers are
preferentially increased.
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Motor Units
pg. 99
A motor unit is made up of a nerve connected to
a number of muscle fibers
– Small motor units contain slow-twitch fibers while large
motor units contain fast-twitch fibers
Motor unit recruitment happens when strength is
required; nerves assist with the action
– The number and type of motor units recruited are
dependent upon the amount of strength required
Muscle learning is the ability to improve the
body’s ability to recruit motor units.
– What is muscle memory?
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Benefits of Muscular Strength & Endurance
pgs. 100 - 102
Improved
performance of
physical activities
Injury prevention
Improved body
composition
Enhanced self-image
and quality of life
Improved muscle and
bone health with
aging
Metabolic and heart
health
Refer to Table 4.1 Physiological Changes and Benefits from Strength
Training
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Types of Strength
Relative
= Weight lifted
Body weight
Absolute
= Weight lifted
Types of Muscle Contractions
pg. 104
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Assessing Muscular Strength
and Endurance
Muscular strength is usually assessed by measuring
the maximum amount of weight a person can lift one
time (1 RM)
– Also can use an estimated maximum test (submaximal
lift)
– Need to train for several weeks before testing
– Retest after 6-12 weeks
Muscular endurance is assessed by counting the
maximum number of repetitions of a muscular
contraction a person can perform to fatigue
Refer to Lab 4.1(pg. 129) for guidelines
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Creating a Successful Strength Training
Program pgs.103 - 107
Static vs. Dynamic Strength Training
Static (isometric) exercise involves a muscle contraction
without a change in the length of the muscle or joint angle
An example is pushing against a brick wall
Considered useful in strength building after an injury/surgery
Isometric contractions are usually held for 6 seconds
Dynamic (isotonic) exercise involves a muscle contraction
with a change in the length of the muscle
Two types
Concentric Contraction (occurs when the muscle
applies enough force to overcome resistance /
shortens)
Eccentric contraction (pliometric contraction) occurs
when the resistance is greater than the force
applied by the muscle / lengthens
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Comparing Static and Dynamic
Exercises pgs. 103 - 104
Static exercises: Isometric exercise
Muscle contraction without a change in the length of the
muscle or the angle in the joint
Require no equipment
Build strength rapidly
Useful for rehabilitation
Dynamic exercises: Isotonic exercise
Muscle contraction with a change in the length of the
muscle
Can be performed without or with equipment
Can be used to develop strength or endurance
Use full range of motion
Are more popular with the general population
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Training Methods
Other Dynamic Methods
–
–
–
–
–
Constant and variable resistance
Eccentric (pliometric) loading
Plyometrics
Speed loading – Kettlebells
Isokinetic
Other Training Methods and Types of Equipment
–
–
–
–
Resistance Bands
Exercise (stability) balls
Pilates
No-equipment calisthenics
- Medicine balls
- Suspension training
- Stones
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Periodization
Notes: ppt only
Periodization is an organized approach to training that
involves progressive cycling of various aspects of a training
program during a specific period. It is a way of alternating
training to its peak during season. The aim of periodization
is to introduce new movements as you progress through
the macrocycle to specify your training right up until you
start the season.
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Periodization Application
Notes: ppt only
Strength and power will eventually plateau and even diminish if the same
combination of sets and repetitions are followed.
The way we avoid this is by applying Periodization or Cycling to our
training plans.
Cycling uses different combinations of volume and intensity, or phases,
each translating into different responses by the body. Traditionally, we
begin a cycle with a base phase then progress to a strength phase and
finish with a peak phase.
Intensity refers to the amount of work required to achieve the activity,
and is proportional to the mass of the weights being lifted. Volume refers
to the number of muscles worked, exercises, sets and reps during a single
session. Frequency refers to how many training sessions are performed
per week.
Periodization
Notes: ppt only
Periodization is the practice of varying training stimuli to enhance longterm fitness and performance gains.
Traditional Periodization programs varied intensity and volumes between
mesocycles. More modern Periodization programs implement variations
between microcycles (daily undulating periodized programs) as well, and
appear to be more effective (Rhea 2002).
It is the practice of splitting a program into distinct time periods, with
each period building on the former periods’ progress.
Periodization Cycles
The three parts of a periodized plan are the macrocycle
(the entire year), the mesocycle (3 – 12 weeks with a
macrocycle), and a microcycle (the actual training week
within a mesocycle).
Macrocycle ( The entire year)
– Mesocycle (3 – 12 weeks with a macrocycle)
Microcycle (week within a mesocycle)
Periodization Phases
Transitional Phase: Beginning of a Mesocycle. Emphasis
on training technique. New exercises are introduced and
practiced. Low Intensity and Low Volume. Example: 1 to 2
set per exercise for about 10 to 12 repetitions.
Endurance Phase: Muscular & cardiovascular endurance is
the focus. Introduction of new movement pattern and
exercises. Lower intensity and Higher Volume. Example: 1
to 3 sets per exercise for about 15 to 20 repetitions.
Periodization Phases
Notes: ppt only
Hypertrophy Phase: Muscle Growth. High Intensity and
High Volume. Example: 5 to 8 sets per exercise for 8 to 12
repetitions
Strength Phase: Greater rest period and slower training
tempos to maximizes motor unit recruitment. High
Intensity and Low Volume. Example: 5 -8 sets per exercise
with 3-5 repetitions per exercise.
Power Phase: The speed and rate of force production is
important. Faster Tempo. Moderate Intensity / Low
Intensity loads and Low Volume. Example: 3-5 sets per
exercise with 5 to 10 repetitions of each exercise.
Applying the FITT Principle
pgs. 107 - 110
Frequency: 2-3 nonconsecutive days/week allowing 1 day
of rest between workouts / or split workouts.
– Based on the ACSM guidelines
Intensity: (Amount of Resistance) Strength requires lifting
as heavy as 80% of your 1 RM; Endurance requires 4060% of your 1 RM
Time: (Repetitions and Sets) 1-5 reps for strength; 15-20
reps for endurance; 8-12 for a combination of both, making
sure each set leads to overload of that muscle group
Type: (Mode of Exercise) target large muscle groups (8-10
exercises) including opposing muscles (example: free
weights, resistance bands, kettlebells).
– Agonist muscle groups
– Antagonist muscle groups
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Muscular Strength F.I.T.T.
pgs. 107 - 110
Strength
F
I
Endurance
2-3 days/week every other day
2-3 days/week
40-60% 1 RM
60-70% 1 RM
T 1-3 sets, 1-5 reps
2-5 sets, 15-20 reps
1 set, 8-12 reps
T
weight training
weight training
1-3 minutes
1-3 minutes
R
60-80% 1RM
Health
weight training
e 3-5 minutes
s
t
Resistance Training Myths
No pain - no gain
Makes you “muscle bound”
Fat can be converted
into muscle
Muscle turns to fat if not used
Has masculinizing effect on women
Is extra PRO consumption necessary?
Warm Up and Cool Down
pg. 109 - 110
Everyone should perform a warm-up prior to
each weight training session
A general warm-up (like walking or easy jogging)
and performing light reps of each exercise is
recommended before every training session
To cool down after weight training, relax for 5-10
minutes by stretching—which could possibly
prevent soreness
Refer to Figure 4.2
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Getting Started and Making Progress
pg. 110
First few sessions
– Should be devoted to learning the movements
– Choose a weight you can move easily 8-12 times; 1 set and
rest 1-2 minutes between exercise
– Goal is to be doing 1-3 sets of 8-12 repetitions
Progress
– “Two-for-two” rule
– General guideline for increasing weight – increase
approximately 5% for each 10 pounds you are currently lifting
– Your rate of improvement depends on how hard you work and
your bodies response to resistance training
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Weight Training Safety
pgs. 111 - 112
Use proper lifting techniques
– ACSM recommends a moderate rate for
each repetition
– Strive to maintain a neutral spine position
during each exercise
Use spotters and collars with free
weights
Be alert for injuries
– R.I.C.E. principle
See the Take Charge box “Safe Weight Training”
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A Caution About Supplements and Drugs
pgs. 112 - 114
Supplement manufacturers often make claims
that their products will promote or enhance sport
performance or physique
Most of these substances are ineffective and
expensive as well as possibly dangerous
Before purchasing and using these products, find
other resources that document these dietary aids
We will Look into Ergogenic Aids during Lecture 9
Refer to Table 4.2
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27
Muscular Strength and
Endurance
Chapter Four
© 2013 McGraw-Hill Higher Education. All rights reserved.