please expain this 5th grade hemmingwy 


CLASSIFYING STRENGTH
Strength can be further classified by determining whether it is anaerobic, aerobic, linear, or
nonlinear. By definition, anaerobic means without oxygen, while aerobic means in the presence
of oxygen. Linear strength means there is a correlating relationship between two variables—
when one variable changes, so does the other in the same way and vice versa. Nonlinear
strength has variables that are not directly correlated. For example, as strength increases (or
decreases), so does muscular power in the same muscle group(s). Though the relationship
may not be balanced as a 1:1 ratio, this is a linear strength relationship. The relationship of
flexibility and maximal strength, on the other hand, is a nonlinear relationship as one is not
directly related to the other. Greater strength does not mean someone is more flexible, nor
does improving one’s flexibility mean they will get stronger.
ANAEROBIC AND AEROBIC STRENGTH
Anaerobic strength activities derive energy from the ATP/CP energy pathway and anaerobic
glycolysis. An anaerobic strength activity can only be sustained for up to 60 seconds before
stored energy is used up. Activities include
• shot put,
• powerlifting,
• high jump,
• golf swing,
• 200- to 400-meter sprint, and
• high-intensity interval training (HIIT).
It takes roughly three to five minutes for the body to restock the cells with adenosine
triphosphate (ATP) or creatine phosphate (CP) after this kind of all-out effort.
Aerobic strength is also known as endurance strength. It is the ability to sustain a submaximal
activity for a longer duration. Aerobic strength requires oxygen for energy and is fueled by
aerobic glycolysis, the oxidative pathway, or gluconeogenesis.
LINEAR STRENGTH:
Two or more strength
variables that are directly
correlated to one another.
NONLINEAR
STRENGTH:
Two or more strength
variables that are not
directly correlated to one
another.
ADENOSINE
TRIPHOSPHATE (ATP):
An energy-carrying
molecule used to fuel body
processes.
CREATINE
PHOSPHATE (CP):
A high-energy molecule
stored in skeletal muscle,
the myocardium, and the
brain.
ENDURANCE
STRENGTH:
The ability to sustain a
submaximal activity for a
longer duration.
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CHAPTER 12 | Concepts of Resistance Training
Table 12.2 Energy System Basics
ENERGY
SYSTEM
WHEN THE
SYSTEM IS
DOMINANT
TYPICAL
ACTIVITIES
TIME REQUIRED
FOR FULL
RECOVERY
ATP/CP 0-10 seconds
Resistance training
Short sprints
Plyometrics
Ballistics
3–5 min.
Glycolysis
10-120
seconds
Badminton
Soccer
Gymnastics
Hockey
Short to intermediate
sprints
20–60 min.
Aerobic
2 min. and
longer
Long-distance running
Swimming
Rowing
Cycling
24–72 hr.
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LINEAR AND NONLINEAR STRENGTH ENDURANCE
Any activity that requires a sustained effort for an extended period is a linear strength
endurance activity. For example, a marathon requires a sustained effort for several hours.
Strength and endurance are directly correlated. Another example of a linear activity is an
800-meter or longer swimming event. These events are cardiovascular in nature—requiring
aerobic energy—but cannot be completed without adequate strength endurance.
A nonlinear strength endurance activity can be anaerobic or aerobic. Examples include
basketball or soccer, in which players use intermittent bursts of agility, speed, and power for
a long duration. Another example is a competitive powerlifter. The athlete must complete nine
maximum lifts to be scored and as many as 20 near-maximum warm-up lifts during the threeor four-hour competition. Because the event has intermittent rest periods and the activities
are not sustained, the activity is nonlinear.
STRENGTH CURVE
The strength curve is a visual representation of the amount of force produced over a range
of motion (ROM). Strength curves differ for exercises and individuals and are important to
understand regarding exercise selection, equipment used, and even when considering tempo
and time under tension during movement execution.
ASCENDING STRENGTH CURVE
In an ascending strength curve, more force is applied toward the end range of motion than
during the beginning or middle phase. For example, during the squat, it is possible to lift more
weight from above parallel to the top of the movement. This means that much lighter loads
would be necessary if starting from below parallel.
DESCENDING STRENGTH CURVE
A descending strength curve is opposite the ascending strength curve. Loads are easier to
leverage at the beginning ranges of motion than in the latter. A rowing exercise uses less
strength at the beginning of the movement than at the end, when the elbows are pulled back.
Exercises with a descending strength curve get more difficult toward the end range of motion.
LINEAR STRENGTH
ENDURANCE ACTIVITY:
Activity that requires a
sustained, all-out maximum
effort for an extended
period.
NONLINEAR STRENGTH
ENDURANCE ACTIVITY:
An activity with intermittent
activity and rest periods.
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CHAPTER 12 | Concepts of Resistance Training
BELL-SHAPED STRENGTH CURVE
In a bell-shaped strength curve, the beginning and ending phases of movement are more
difficult than the middle. An example is the biceps curl. The biceps muscle is at a mechanical
disadvantage at the bottom of the curl. Between 60 and 110 degrees of flexion, the biceps
muscle gains leverage and produces more force. At the end range of motion, the biceps
muscle is at a mechanical disadvantage again and therefore has less potential force
production.
Joint Angle
Bell-Shaped
Descending
Ascending
Force
Figure 12.1 Strength Curves
STRENGTH TRAINING AND TRAINING PRINCIPLES
While there are many general fitness principles and training variables, there are some that are
specific to strength and resistance training - load, intensity, time under tension, and exercise
selection, to name a few variables. It is through proper application of these variables, and
the way that resistance training can create overload, that adaptations such as maximizing
strength, power, and hypertrophy can be achieved efficiently.
Muscle fiber type also plays a role in the adaptations of an individual. Those with a higher
amount of type II fibers will have greater success in building muscle size, strength, and power
relative to those with predominantly type I muscle fibers. Those with mostly type I fibers are
physiologically predisposed to have greater success with endurance gains.
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PRINCIPLE OF SPECIFICITY
Exercises typically progress from a general type (simple) to a more sport-specific or goaloriented type (complex) as training continues. Assessments allow a trainer to uncover a
client’s starting point and plan the appropriate progression for their goals and abilities.
To improve general health, fitness, and functional capacity, a balance of several kinds of
exercise should be included in the training program. The training goal helps determine the
ideal balance of general and specific exercises.
TEST TIP!
A client’s goal should determine the specific types of training modalities chosen. For
example, to become better at throwing, the muscles involved in throwing, like the
pectoralis major, must be trained. How they are trained is the question. The mechanics
(the throwing motion) of throwing must be trained and not just the individual muscle
as in a chest press.
General Exercises
General exercises can also be considered foundational exercises. In other words, movements
can produce overall strength and efficiency gains but do not necessarily transfer to
performance of specific skills. Isolation and compound movements using free weights,
cables, or machines fall into this category. General exercises include the bench press, cable
row, plank, squat, and leg press.
Benefits of including general exercises include a reduced injury risk and an increase in the
following:
• Muscle hypertrophy
• Motor unit recruitment
• Bone density
• Connective tissue strength
• Increased cardiovascular capacity
ISOLATION EXERCISES
Isolation exercises are single-joint movements that primarily activate individual muscles or
smaller muscle groups. The biceps curl, triceps extension, leg curl, and leg extension are
examples. Isolation exercises improve muscle control, strength, and hypertrophy while also
GENERAL EXERCISES:
Foundational exercises that
train overall strength.
ISOLATION EXERCISES:
Single-joint exercises
that primarily activate an
individual muscle or muscle
group.
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CHAPTER 12 | Concepts of Resistance Training
working to balance musculature—as long as both agonist and antagonist muscles are
worked—and enhance the physique and strengthen connective tissue.
Isolation exercises also help target muscles that are not fully activated during compound
movements. For example, research has found that hamstring activation is inherently low
during exercises such as the leg press and squat. To help strengthen the hamstrings, one
can perform isolation movements.
COMPOUND EXERCISES
Compound exercises engage multiple joints and many muscle groups throughout a range of
motion. Compound exercises increase muscle hypertrophy and bone density and strengthen
connective tissues. Examples include
• squats,
• lunges,
• deadlifts,
• bench press, and
• chin-ups.
Applying specificity to exercise selection means training the musculature as well as the
neuromuscular connections that innervate the movement. Select exercises use the same
movement pattern that a client wants to improve. For example, to increase strength through
the squat movement, a client will train primarily with the squat, not the leg press. This ensures
the prime movers, synergists, and stabilizers for a squat are all addressed and strengthened
appropriately and in proportion. This also facilitates improvements in coordination of the
musculature involved in an exercise such as the squat as opposed to the leg press.
TEST TIP!
Most major movement patterns in everyday life and in sports are multi-joint movements
that can be trained with compound exercises. This means not only are they a good choice
to train multiple muscle groups at once, but they have direct translation to function.
COMPOUND
EXERCISES:
Multi-joint movement
exercises that require the
use of multiple muscles or
muscle groups.
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Specific Exercises
Exercises that directly improve performance and are predominantly skill-based are specific
exercises. The best specific exercises target a particular skill set and, when performed
properly, enhance that ability. A baseball pitcher improves pitching skills and speed by
practicing pitching. Lacrosse athletes responsible for scoring, called “attackers,” need to
practice shooting to improve shooting skills. Therefore, sport-specific practice should never
be disregarded for strength and conditioning.
Specific exercises must be like the target activity and mimic specific:
• joint movements,
• movement direction,
• range of motion, and
• speed of movement.
Examples of specific exercises include the standing single-arm chest press, which is
transferrable to the sports of football, rugby, and ice hockey, as well as any other sport where
the athlete must push away an opponent.
CROSS-BODY EXERCISES
Cross-body exercises more closely mimic the natural movement of the body in space.
Considering how humans walk, the arm and shoulder on one side “link” diagonally to the hip
and leg on the other side so that:
• the left arm and shoulder are forward,
• the left hip and leg are back,
• the right arm and shoulder are back, and
• the right hip and leg are forward.
The terms “x-factor” and “serape effect” were coined to refer to the interaction between
various muscles causing the body to move in a crisscross manner, primarily referring to
trunk rotation. These muscles—ipsilateral rhomboids, serratus anterior, external abdominal
obliques, contralateral internal abdominal obliques, and adductors—attach via fascia in a
crisscross manner around the body.
Although research is being done regarding the x-factor, there are no proven training methods.
However, because cross-body action is a natural human movement, it should be included
in a well-balanced strength training program. Many recent studies have tried to quantify the
SPECIFIC EXERCISES:
Exercises that directly
improve performance and
functional capacity.
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CHAPTER 12 | Concepts of Resistance Training
x-factor to determine how best to train for more power in, say, a golf or baseball swing. Like
plyometric exercises, the x-factor muscles use the stretch-shortening cycle. Researchers
suggest that flexibility and efficient interaction of x-factor muscles may increase performance.
For example, a 2016 study on badminton technique suggests that training focused on
increasing the efficiency of cross-body movement should focus specifically on how the x-factor
is incorporated into the kinematic chain of the arm and the racket. A more recent study found
that although skilled golfers had greater rotational flexibility, they did not use that flexibility to
increase x-factor efficiency to improve clubhead speed.
To load x-factor muscles, clients can use single-arm or offset loading (uneven weights) and
vary the stance. Examples of exercises include single-arm standing cable press, high-to-low
cable chop, and suitcase carry.
EXPLOSIVE EXERCISES
Exercises that engage many muscles in a sequential, powerful, quick movement are explosive
exercises. Soccer, tennis, boxing, shot put, Olympic lifting, sprinting, and many other sports
require explosive movements. Explosive movements follow a triphasic pattern of alternating
bursts of agonist and antagonist muscle activation.
Phase 1—eccentric: the loading phase of the movement
Phase 2—amortization: the transition time between phase 1 and phase 3
Phase 3—concentric: agonist taking advantage of the stored energy from the eccentric
action and firing explosively
Choosing the right explosive movements is key to program success. Since most sports are
explosive or ballistic in nature, adding fast, ballistic movements into the training program
improves neuromuscular coordination and control and prevents injury. Movements should be
trained in various directions as power is direction-specific.
Finally, when considering specificity, the following should be noted:
A recent study measured electrical activity of the upper and lower lateral hamstrings and the
upper and lower medial hamstrings during the stiff-legged deadlift and lying leg curl exercises.
When compared with the stiff-legged deadlift, the lying leg curl caused significantly greater
activation of the lower lateral and lower medial hamstrings. Since each movement offers unique
but complementary benefits, it is recommended to include at least one movement focused at the
hip joint (deadlift) and one focused at the knee joint (leg curl) to properly train the hamstrings.
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No single type of resistance exercise can address the various needs of the human body.
Rather than using just one type of resistance, the client should vary the resistance throughout
the training cycles based on the physical qualities that are most desired.
PRINCIPLE OF PROGRESSIVE OVERLOAD
For fitness to progress, the body must be forced to adapt to or overcome a stress greater
than what is normally encountered. Range of motion, volume, intensity, density, and frequency
can all be progressively overloaded to influence adaptations. For the trainer, it is important to
understand which acute training variable to overload for the desired result.
PRINCIPLE OF REVERSIBILITY
The idea of “use it or lose it” applies to all aspects of fitness. For example, researchers
followed an Olympic rower who took eight weeks off from training after hitting peak fitness
during the Olympic games. It took 20 weeks of training to return to their previous fitness level
after a two-month hiatus. Several observations have been made regarding detraining and
resistance training:
• Detraining happens about three to four weeks after training stops.
• Muscle atrophy may occur as soon as two weeks after training stops.
• Endurance performance declines by 4–25 percent after just three to four weeks of
no exercise.
• VO2 max goes down by 6–20 percent at around four weeks of detraining.
• Flexibility declines by 7–30 percent after four weeks of detraining.
• Bed rest or immobilization increases the rate of muscle atrophy.
TAPERING
Tapering is a planned reduction in training to avoid detraining and increase gains prior to
competition. Tapering should meet three objectives:
1. To reduce fatigue as much as possible
2. To increase or maintain fitness at competition levels
3. To enhance specificity
Recent research has found that tapering strength training can lead to performance gains
from 0.5–6 percent, the average being 3 percent. This can be significant. For example, if a
powerlifting athlete peaks at 2,000 pounds, then a taper could increase their maximal lift by
60 pounds.
ATROPHY:
The wasting away or loss of
muscle tissue.
TAPERING:
A decrease in training
volume or frequency to
allow the body adequate
rest and recovery.
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CHAPTER 12 | Concepts of Resistance Training
During a taper, intensity must remain at or slightly above competition levels. Volume (reps x
sets x weight) and frequency then should be reduced.
Some studies suggest that volume be reduced by 30–70 percent to improve maximal
strength. However, the principle of individual differences comes into play here as well as the
fitness-fatigue paradigm:
• Individual A has been following an intense training program for 10 weeks and has
a competition in two weeks. This person may benefit from a 70 percent drop in
training volume.
• Individual B has been training intensely for four weeks and has a competition in
two weeks. This person may benefit more from a one-week taper at 35–40 percent
reduced volume.
Tapering is not only for elite athletes. Before moving from one training cycle to another,
general fitness program participants also benefit from a taper period.
PHYSIOLOGICAL ADAPTATIONS TO ANAEROBIC EXERCISE
Anaerobic exercise uses glycolysis without the presence of oxygen. In practical terms, it is
harder and shorter movement and can increase the size and quantity of fast-twitch fibers.
More fast-twitch muscle fibers means greater strength, power, and larger muscle size.
Anaerobic exercise includes short-duration activities such as weightlifting (resistance
training), powerlifting, sprints, and high-intensity intervals.
Anaerobic activity cannot last as long as aerobic activity. The lack of oxygen triggers a buildup
of lactic acid and excess protons (H+), causing pain and muscle fatigue. However, individuals
who engage in anaerobic activity more frequently develop a higher threshold to lactate and
proton buildup.
ANAEROBIC EXERCISE:
Short-duration muscle
contractions that break
down glucose without using
oxygen.
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In addition, anaerobic exercise increases glycolysis—the breakdown of glucose for energy.
This further increases levels of ATP and creatine phosphate (CP), which can be quickly
changed to ATP and used for energy. Intramuscular creatine levels also increase, helping
supply energy for muscle contraction.
Muscle hypertrophy occurs with an increase in mitochondria, myoglobin, extracellular and
intracellular fluid, capillarization, and fusion of muscle fibers to surrounding satellite cells. In
addition, resistance exercise generates thicker myofibrils, or contractile tissue, increasing the
size of individual muscle fibers.
Except for muscular hypertrophy, the cellular changes found in endurance training do
not usually happen with resistance training. However, resistance training increases the
development of connective tissue. The epimysium and tendons become stronger to support
more powerful muscular contractions and prevent injury.