By James Giordano, Ph.D.
Whether in the sports health care or rehabilitative setting, physiologic adaptations
to exercise-induced stress are directly related to training-specific variables.
In seeking to facilitate progressive improvement in human physical performance,
individual genetic factors (the adaptational ceiling), the current conditioning
level and age- and sex-related variations must all be considered in designing
and implementing the training program.
In addition, the goals of the participant relative to the target activities
are guiding factors in determining the physiologic (anaerobic, aerobic or combined
performance) basis of the program. Toward these ends, it is critical to develop
programs that afford ongoing stimulation for adaptational enhancement in a calculated
paradigm that maximizes progress and reduces the probability of injury and de-compensating
fatigue (overtraining).
Of primary importance is a needs analysis to assess the current level of conditioning
relevant to the desired scope of performance enhancement. Baseline evaluations
of body composition (somatotype, body-fat percentage and body mass index calculations),
anthropometry (axial and appendicular girth measurements) and flexibility (e.g.,
upper and lower extremity stretching and range of motion, sit-and-reach testing)
should be done. Addressing any current or previous injury and/or health conditions
is also required. These comparative indices will serve to gauge improvement
and as precautionary variables, respectively.
Conditioning Assessments
For strength-related performance, initial assessments should include muscular
strength (one repetition maximum or multiple repetition testing), anaerobic
capacity (line drill or shuttle run testing) and muscular endurance (timed maximal
sit-ups and/or push-ups, submaximal timed repetitive lifting).
For aerobic performance, the evaluative battery could utilize aerobic capacity
(1.5-mile run, stationary bike VO2 max assessments) and agility (T-course, Edgren
side-step) tests. A combined performance evaluation would include muscular strength,
endurance, aerobic capacity and speed (e.g., 40-yard sprint) testing.
The subject’s age and sex must be considered in designing the training
program. Prepubescent children can participate in physical training and make
significant performance gains due to neuromuscular adaptation rather than purely
muscular factors. Adolescents are responsive to their inherently maturing hormonal
state, and they respond to both resistance-based and aerobic-based training
with increasing similarity to adults in terms of neural activation, muscular
fiber differentiation and metabolic alterations.
In the geriatric population, age-related decline in muscle mass, bone density
and metabolic activity are all responsive to training, and graded, but volume-
and intensity-progressive resistance exercise has been shown to be particularly
beneficial in diminishing detrimental trends.
In all cases, careful consideration of health factors and close monitoring of
the specifically designed training program are essential.
Gender Differences
A number of physiological differences exist between men and women. Males have
greater overall muscle mass, can generate greater muscular force output (through
both greater muscle enzyme activity, hormonally-induced muscular cross-sectional
area and biomechanical advantages), have a lower percentage of compositional
body fat and comparatively greater hemoglobin concentration and larger heart
size.
However, many of these variables are relative, and females’ response to
training is generally as favorable as males at a comparable conditioning level.
Specific concerns in female performance training include generally lesser upper-body
strength, biomechanical variables (e.g., Q angle, ligamentous laxity and dimensions)
affecting the lower extremity that may predispose knee injuries and metabolic
variations consequential of the menstrual cycle that reciprocally interact with
physical training and body composition.
Designing Specific Regimens
Respective of these variables of baseline conditioning, age and sex, all training
programs must then be optimized to ensure progressive improvement in outcomes.
The initial needs analysis must consider the movement patterns, physiologic
demands and injury potential of the sport or activity to which the training
will be applied.
All training programs (resistance, aerobic, combined) must appreciate the concept
of the physiologic capacity to specifically adapt to imposed demands (the SAID
principle). Inherent in this approach is the development and implementation
of a training program that meets the needs of the performance goals with high
specificity. Strength, power, endurance and speed can all be enhanced by protocols
that focus upon physiologic components required for these endpoints.
It is important to note, however, that the physiologic changes induced by strength
and endurance training differ, and high-volume, combined training regimens may
not be complementary or optimal. Thus, training must be designed to utilize
selected core (multi-joint structural and power movements), assistance (single
joint isolative movements) and conditioning (cardiovascular) exercises, performed
in a specific order, with progressive training loads and volumes according to
a scheduled frequency.
The specific training program must incorporate a progressive cycle of varied
overload and recuperative rest to achieve maximized adaptation and linear gains
in performance. This can only be accomplished through diversification of training
type, intensity and volume across a predetermined span of time, using the process
of periodization.
After establishing defined short (one- to two-month), intermediate (six-month)
and long-range (12- to 18-month) performance goals, the quantity and quality
of training are varied by utilizing high-intensity/low-volume, high-volume/low-intensity
exercise and rest periods in a cyclic approach. Characteristically, variation
occurs at two- to four-week intervals known as microcycles, with progressive
increases in intensity and volume occurring over a two- to six-month period
known as a mesocycle. The linear increases that occur as a consequence of physiologic
adaptation to periodized intensity/volume training and active rest are the product
of the 12- to 18-month training macrocycle.
This approach facilitates ongoing, longitudinal performance enhancement and
prevents the fatigue, poor recuperative capacity, performance decline, injury
vulnerability and motivational disenfranchisement of overtraining. Specific,
periodized training can be employed in a variety of exercise applications, and
the proper use of such cyclic progression promotes optimal, time-efficient results
and the achievement of consistent performance enhancement.
About the author: James Giordano, Ph.D., is associate professor of pathology
and physical medicine at Texas Chiropractic College and serves as the director
of institutional research and the pain management program for the Moody Health
Center, Pasadena, Texas. He is the director of the human performance program
of the Baylor Sports Medicine Institute, a diplomate of the American Academy
of Pain Management, a certified exercise physiologist and a noted seminar presenter.
E-mail jgiordano@txchiro.edu for more information.
Selected References
1. Brooks, G., Fahey, T., and White, T., Exercise Physiology: Human Bioenergetics
and Its Applications, 2nd ed., Mountain View, CA: Mayfield, 1996.
2. Canavan, P. (ed.), Rehabilitation in Sports Medicine, Stamford, CT: Appleton-Lange,
1998.
3. Dudley, G., and Fleck, S., “Strength and Endurance Training: Are They
Mutually Exclusive?” Sports Medicine 4:79, 1987.
4. Fleck, S., and Kraemer, W., Designing Resistance Training Programs, 2nd ed.,
Champaign, IL: Human Kinetics, 1997.
5. Gordon, S.L. (ed.) Sports and exercise in midlife. Park Ridge, IL: American
Academy of Orthopedic Surgeons, 1994.
6. Hoffman, M., Sheldahl, L., and Kraemer, W., “Therapeutic Exercise,”
In: Rehabilitative Medicine: Principles and Practice, 3rd ed., J. DeLisa &
B. Gans (eds.), Philadelphia: Lippincott-Raven, 1998.
7. Komi, P. (ed.), The Encyclopedia of Sports Medicine: Strength and power,
Oxford: Blackwell Scientific, 1992.
8. Safran, M., McKeag, D., and VanCamp, S. (eds.), Manual of Sports Medicine,
Philadelphia: Lippincott-Raven, 1998.
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