|
Researched
and Composed by
Gabriel “Venom” Wilson, BSc. (Hons), CSCS
What is Stress
When you hear the term “stress” what is the first thing that comes to
your mind? For many of us, words such as disease, worry, and
apprehension always seem to pop up.
While stress can have deleterious effects, evidence suggests that stress
plays an essential role in developing a healthy body, that is able to
cope with the various demands thrown our way on a daily bases.
The topic of stress has been studied for almost a century now. Yet,
there is no general consensus on the definition of stress. Therefore,
the purpose of this paper was to define stress.
Simmons (2006) suggests that definitions of stress typically contain one
or more of the following four elements: stressors, adaptations
(responses), perceptions (cognitive/emotional), and effects (acute and
chronic).
Selye (1936) suggested that a stressor was anything that causes the
stress response. Stressors may consist of various stimuli in the
environment, such as the climate or social conditions. The organism then
responds, or adapts to the stressor. Wilson J. and Wilson G. (2005)
suggest that an adaptation is an acute or chronic
modification of an organism or parts of an organism that make it more
fit for existence under the conditions of its environment.
Perceptions can be defined as stimuli that an organism decides to take
into its mind, based on importance (Simmons, 2006). Perceptions can
determine what stimuli in the environment act as stressors, based on the
organism’s appraisal of the stimuli. And finally, the results of the
stress response can manifest themselves acutely or chronically, and be
beneficial or deleterious
To tie these altogether with an example, suppose a male athlete is
squatting 400 pounds (the stressor), the heaviest he has ever lifted. As
the athlete prepares to perform the lift, he begins to feel
apprehension, because he has never lifted this much before, and as an
athlete, improving his lifts are clearly important to him (this would be
the perception and interpretation; notice how it is based on task
importance). In response to his apprehension, his heart rate and
respiration begins to rise (acute adaptations, in response to a
perceived threat). The athlete then performs the lift successfully, for
4 reps. During the subsequent training session, he finds that he can
perform 8 reps with the same weight (a chronic beneficial adaptation).
This example typifies the stress response.
Keeping these 4 elements of stress in mind, this paper will begin its
discussion on the definitions of stress with the father of stress, Hans
Selye.
During his days as a Hungarian scientist, Selye observed that his
patients with diseases had many similar symptoms, regardless of the
infection. These included a loss of appetite, inflamed tonsils, and pain.
In this context, Selye suggested that sickness could be studied in
general, rather than specific to the disease itself (McEwen, 2002).
To test his hypothesis, he examined the effects of various stressors
such as toxins and sudden changes in temperature on rats. He observed
that every stressor caused a similar response, suggesting that the body
had a general mechanism to cope with stressors. This lead him to define
stress as the nonspecific response of the body to any demand made upon
it to adapt, whether that demand produces pleasure or pain. Based on the
general nature of stress, he developed the infamous General Adaptation
Theory.
Figure 1.0
Hans Seyle’s General
Adaptation Theory (Adapted from Wilson and Wilson, 2005, a)
Figure 1 graphically depicts Hans Seyle’s General Adaptation Theory.
This theory suggests that stress is composed of three phases: alarm
reaction, stage of resistance, and stage of exhaustion. During alarm
reaction, the introduction of a stressor leads to a decrease in
performance. Following this is the stage of resistance, in which the
organism’s defense mechanisms fight to gain resistance. This is known as
adaptation and is characterized by elevated levels of homeostasis.
Lastly, if the stimulus is continuous then the individual would plateau
or experience maladaptation. The maladaptation according to Seyle
reflected similar symptoms to the Alarm reaction stage, and was the
result of a depletion of the organisms defense mechanisms caused by
chronic stress (Wilson and Wilson, 2005, a).
Seyle suggested that stress could be further broken down into two
elements—distress and eustress. Distress was the damaging effects caused
by stress, and could result in a decline in performance for athletes, or
promote pathogenesis (diseases). Eustress was the advantageous effects
of stress, and promoted growth and development.
Another popular theory is fitness fatigue model developed by Banister,
Calvert, and Savage (1975).
Figure 2.
Banisters Fitness Fatigue Model (Adapted from Wilson and Wilson, 2005,
b)
Figure 2 graphically depicts the fitness and fatigue model. The model
views adaptation as a constant flux of growth and decay and further
growth of the combination of two intervening variables on
performance. Banister et al. (1975) denotes these variables as fitness
or positive benefits and fatigue or negative effects, while performance
is seen as the difference between the two. Therefore, if fatigue is
greater than the fitness gains, performance will suffer, and visa versa.
Based on these 2 models, and various other definitions of stress,
athletes have used these principles to develop advanced training
programs including periodization and tapering. For more information on
how to manipulate exercise and stress for human performance, refer to
the science of training variables.
And refer to this on bones by Wilson (2004)
to see how stress can enhance bone growth.
Another pioneer in the study of stress was Walter Cannon (1929). Cannon
discussed the body’s tendency to keep itself within narrow tolerance
limits necessary to sustain life (homeostasis). In the presence of a
stressor that would cause an imbalance in homeostasis, Cannon suggested
that the body responds in a stereotypical pattern of psycho
physiological reactions to prepare to meet a survival threat (the stress
response). He further posited that this response involved the famous
fight or flight response, which initiated various adaptations such as
shutting down digestion, tensing muscles, and piloerrection (hair stands
up), all of which would activate the system so that it could handle the
perceived or experienced stressor. The fight or flight response is
discussed in detail in Part 2 of this series.
Figure 3.
The Balance Between
demands and response capabilities (Adapted from bwilson)
Figure 3 graphically depicts McGrath’s definition of stress. McGrath
(1970) suggested that stress is the perceived imbalance between demands
and response capabilities when failure to meet the demands is deemed
important. Therefore, if the organism perceives that the demands placed
on it are greater than its response capabilities, and the situation is
important, stress will increase; conversely, if the situation is not
important, or if the organism perceives its response capabilities exceed
the situational demands, stress will decrease. This definition focused
on the psychological state which triggered the stress response. Going
back to the example discussed a few paragraphs ago, the athlete had a
heightened stress response, because he had never lifted that much weight
before, and was unsure if he had the capacity to handle the demands of a
400 pound squat.
Building on the work of McGrath, Martin (as reported by Simmons, 2006)
suggested that stress could be defined as uncertainty * importance.
More recently, Inouye (2006) suggested that stress is anything that
causes the body to adapt.
All of these definitions of stress are helpful in understanding the
stress response; yet, by themselves, they fail to adequately define the
stress response. This does not mean that any of them are invalid; what
it means is that before discussing stress, it is vital that the writer
defines what definition of stress they are using, because stress is such
an ambiguous term that can take on numerous meanings. As has been
displayed, stress can be cognitive or physical (or both); it can be
beneficial or deleterious; it results in adaptation or maladaptation;
and it can be acute or chronic. Perhaps a definition which combined all
these factors would help clarify on this term.
In this context, the current author suggests that stress can be defined
as the perceived or experienced imbalance between demands and response
capabilities when failure to meet the demands is deemed important, or
results in a disturbance in homeostasis. Typically, it must be inferred
from acute or chronic adaptations or maladaptations.
This definition clarifies on several points. It discusses the impact of
a stressor (or demand); both physiological (homeostasis and experience)
and psychological (perception) responses to stress; acute and chronic
adaptations of the stress response; and the positive or negative effects
of stress. It also suggests that stress is a hypothetical construct that
cannot be directly observed, but rather must be inferred based on acute
or chronic adaptations or maladaptations.
To learn about the physiological mechanisms behind the stress response,
click
Here.
Keep it Hardcore,
Venom
Vice President of ABCbodybuilding.com
Venom@abcbodybuilding.com
References
-
Banister, E. W.,
Calvert, T. W., Savage, M. V. (1975) A systems model of training for
athletic performance. J. Sports. Med. 7, p.57-61.
-
bwilson.
http://home.sandiego.edu/~bwilson/balance.jpg
-
Inouye, C (2006).
Exercise and Stress Lecture. California State East Bay.
-
Joseph E.
McGrath, ea., Holt, Rinehart and Winston (1970).Interpersonal Stress
in Isolated Groups. Social and Psychological Factors in Stress.
-
McEwen, Bruce
(2002). The End of Stress As We Know It. Joseph Henry Press.
-
Selye, H., (1936)
A Syndrome Produced by Diverse Nocuous Agents, Nature (July).
-
Simmons, J
(2006). Exercise and Stress Lecture. California State East Bay.
-
Canon, Walter B.
1929. Bodily Changes in Pain, Hunger, Fear and Rage. New York:
Appleton.
-
Wilson J., Wilson
G. (2005, a). Periodization Part I – History and Physiological
Basis. Journal of HYPERplasia Research.
http://www.abcbodybuilding.com/periodization1.php
-
Wilson J., Wilson
G. (2005, b). Tapering Part 1 - Two Factor Theory. Journal of
HYPERplasia Research.
http://www.abcbodybuilding.com/taper1.php
-
Wilson J. (2004).
The Mechanics of Bone Tissue Part I-III. Journal of HYPERplasia
Research.
© ABC
Bodybuilding Company. All rights reserved. Disclaimer
|
