INTRODUCTION
When considering the variables that make up the training program (i.e. training load, training volume, exercise selection, training frequency, etc.) as well as the millions of potential combinations of these variables, it is easy to loose focus of the purpose of training. In such as situation, erroneous and invalid training information may spread from any number of sources. In order to establish the primary purpose of training, it is necessary to consider the nature of training; namely, its stressful nature. In addition, the acute positive and negative effects of training, along with their cumulative effects, must be considered. The purpose of this paper is not to provide prescription guidelines for sets and repetitions, as the effectiveness of such guidelines would certainly be highly individual. Rather, the purpose is to provide a logical basis from which training may be appropriately sequenced for athletes of any level of preparedness.
THE STRESS OF TRAINING
“Stress is the state manifested by a specific syndrome which consists of all the nonspecifically-induced changes within a biologic system” -Hans Selye
Biological stress is fundamentally nonspecific in its cause, manifesting as specific and quantitative physiological adjustments in the body (Selye, 1978). More specifically, chronically subjecting the body to “stressful” weight training involving heavy loading will undoubtedly trigger a general alarm response from the body. However, this response will initiate specific and unique adaptations in the effected systems, such as a shift in fiber type from IIB to IIA in the muscle tissue (Fry, 2004) or enhanced motor unit recruitment and synchronization in the nervous system (Sale, 1988). The capacity of an organism to adapt is essential, as stress is ever-present in one form or another. This reactive element of living tissue is the foundation of life (Selye, 1978), allowing the organism to maintain a stasis with its surrounding environment and its demands.
Based upon the preceding knowledge of stress and adaptation, Selye (1978) developed a so-called syndrome of stress, also known as the General Adaptation Syndrome (GAS; An adapted version of the GAS may be found in Figure 1). Much of the periodization of training information has been based upon this model of stress response. According to the GAS, following exposure to a stressor the organism enters into a state of alarm. Given the stimulus is within the organism’s adaptive capacity, a resistance is developed against the stressor in an attempt at self-preservation. If the stress is applied for a prolonged period of time, the adaptive capacity of the organism is compromised and exhaustion develops. This maladaptive response to stress in the traditional model leads to disease or death of the organism. When considering the stress of training, we must refer to resistance as a positive adaptation subsequent to training. When the training stimulus is prolonged without necessary variation, the so-called exhaustion stage may manifest as a long-term decrement in performance; also known as the overtraining syndrome (Fry, 1998). At the onset of “exhaustion”, a more short-term maladaptation to training known as overreaching may develop (Fry, 1998). This state is often deliberately imposed by training at excessively high intensities or volumes for a relatively short period of time (Fry, 1998). Following a period of rest, performance may return to levels above that prior to overreaching. Although acutely effective at increasing performance, the long-term efficacy of such training methods has not been established. It is possible that placing such a large demand on the adaptive abilities of the athlete may comprise the long-term stability of the desired training effect.
The GAS represents a general representation of the body’s response to stress. However, as previously mentioned, stress can lead to highly specific adaptation. Selye (1978) proposed a Local Adaptation Syndrome (LAS) to model how the organism may respond in the tissues affected most by a stressor. The LAS has important implications to training because it establishes that stressor X will result in adaptation Y in a given tissue. For example, maximal hypertrophy of type I and II muscle fiber occurs utilizing training loads of roughly 80-87.5% of 1RM (Fry, 2004). If the primary training goal is developing muscle size, then training with loads below 80% 1 RM must be considered solely supplemental; possibly only used for warm-up and restoration purposes. This understanding of how to optimally manipulate the physiology is a crucial component of training. The LAS may also be adapted to include general training effects. For instance, if the athlete requires a certain degree of maximal strength for sporting success, this quality may only be developed optimally by including near maximal (upwards of 100% 1RM) training loads in the training program. The same phenomenon holds true for specific types of muscle actions. If the abdominal muscles must function in a static state during competition, then the majority of training for these muscles must be isometric. If one quality is to be optimally developed, then all other training must be limited in its utilization. After all, the primary training stimulus should always result in the greatest rate of adaptation (Myslinski, 2003). From Selye’s work, we can conclude that all training is stressful. More over, stressful training is essential for obtaining improved performance, given the stress is not prolonged, thus enabling a maladaptation or compromise of training effect. In addition, the training stress must be specific if we are to promote the desired adaptation. However, the GAS is not a perfect model for training. Its main deficiency is the proposed unified response to stress (Chiu and Barnes, 2003). To elaborate further, it is necessary to introduce a different model.
THE FITNESS-FATIGUE MODEL
The Fitness-Fatigue Model (Bannister, 1991; Figure 2) suggests that training stressors produce different physiological responses (Chiu and Barnes, 2003). The model is based on a baseline from which training stressors cause a deviation. Following training, 2 after-effects manifest. The first after-effect is the Fitness after-effect, which is positive. This effect is primarily neurological, promoting optimal activation of the neuromuscular complex and myotatic stretch reflex, as well as limiting force inhibition (Chiu and Barnes, 2003; Hakkinen, 1995; Linnamo, et al., 2000). In addition, there is an increase in central nervous system activity as evident by increased sympathetic nervous system activity (Fry, 1998). The second after effect is the Fatigue after-effect, which can be both neurological and metabolic in nature (Chiu and Barnes, 2003). The neurological “fatigue” can be indicative of decreased sympathetic nervous system activity (Fry, 1998), with the metabolic fatigue being associated with decreased availability of energy substrates (Chiu and Barnes, 2003; Hakkinen, et al., 2003).
Following training, a large fatigue effect results in decreased performance, comparable to Selye’s alarm stage (Chiu and Barnes, 2003). As fatigue dissipates, the fitness after-effect increases, leading to improved performance or adaptation through supercomponsation. If training ceases, then both effects return to baseline. Implications for training are two-fold. First, successive training sessions must occur as fatigue is dissipating and fitness levels are maintained. This will eliminate the exponential accumulation of inter-session fatigue. Secondly, periods of rest or unloading must be included in the training plan every 3-6 weeks, allowing cumulative fatigue to diminish. Using the Fitness-Fatigue model as a basis for planning training sessions may altogether eliminate the risk of developing the overtraining syndrome, given its application is appropriate and individual differences amongst athletes are considered.
The magnitude and duration of the after-effects is dependent upon the training load, training economy (a function of rate of training), and total work performed (Chiu and Barnes, 2003). More over, the magnitude of after-effect depends upon the type of training (Figure 3); consisting of either maximal effort (near maximal and maximal loads), dynamic effort (maximal acceleration) or repetitive effort (high volume)(Siff, 2000). When planning training, maximal and dynamic effort must always precede repetitive effort during the training session (Chiu and Barnes, 2003). This is due to the large and immediate fatigue associated with high volume training. For sub-elite athletes, dynamic effort training must always precede maximal effort training in order to avoid undue fatigue (Chiu, et al., 2003). For qualified athletes, performing maximal effort training prior to dynamic effort training may provide a potentiation effect, acutely improving performance (Chiu, et al., 2003). The same dynamic holds true for planning training over the course of the week. Because the fatigue after-effect associated with dynamic effort training is shortest, this training must be performed early in the week, followed by maximal effort training soon after on a subsequent day (Chiu and Barnes, 2003). Because of the lasting fatigue associated with the repetitive effort method, this training must occur later in the week when 1-2 days of rest may allow cumulative fatigue effects to dissipate (Chiu and Barnes, 2003). This relationship is especially important for athletes preparing for competition. In the 1-2 weeks prior to competition, a dramatic decrease in volume is utilized in order to diminish accumulated fatigue after-effects from training. By employing high intensity loads coupled with minimal training volume just prior to competition, Fitness after-effects may be “ramped” (Chiu and Barnes, 2003) while fatigue continues to diminish. It is clear that training stress is comprised of a Fitness and Fatigue component. Within these components, various types of strength training have different contributions. With this in mind, it is possible to more optimally organize long-term training to positively manipulate the Fitness and Fatigue after-effects associated with training. The key is in the sequencing of successive training blocks devoted to developing distinct qualities of strength, in which previously trained qualities are maintained and built upon while managing accumulating fatigue and securing the desired training effect.
SEQEUNCING OF TRAINING
The ultimate goal of training is functional reconstruction of the athlete, resulting in long-term adaptation and maintenance of the training effect. These effects develop subsequent to the training of special strengths (figure 4). Although the demands of sport greatly vary, all require the expression of multiple special strengths. It is in this regard that the traditional model of periodization, utilizing rotational and unidirectional separation of motor abilities, is insufficient (Myslinski, 2003). Since significant blocks of time are devoted to the development of individual strengths, the concurrent development or maintenance of other strengths is ignored, thus leading to a detraining effect. Therefore, it is necessary change the targeted special strength frequently while maintaining all non-targeted traits with retaining loads in order to ensure a linear improvement in performance (Myslinski, 2003; Dyachov, 1964). In order to develop multiple traits simultaneously, either a concurrent or concentrated model of loading must be employed (Siff, 2000).
CONCURRENT LOADING
A scheme of concurrent loading utilizes training focusing on multiple special strengths during the same training session, microcycle or mesocycle (Siff, 2000). Were schemes focusing on prolonged periods of unidirectional loading prove insufficient at promoting specific adaptation to competition activities, concurrent loading allows for the simultaneous improvement of upwards of 2-3 different motor regimes (Siff, 2000; Zatsiorsky, 1995). Figure 5 offers a representation of concurrent loading in regards to the corresponding Fitness and Fatigue after-effects associated with this loading over the course of the microcycle. It should be noted that training should resume following the brief unloading period to take advantage of the performance supercompensation.Concurrent loading schemes seem to be most appropriate for beginners and lesser-qualified athletes as a means for improving sport-form, as well as a basis from which to plan future training. This is especially true for team sports were the athlete has only a finite period of time prior to competition from which to maximize training. However, for elite athletes concurrent loading schemes may provide little benefit (Verkhoshansky, 1977). That is not to say that concurrent loading is of no use to this population. But rather, highly qualified athletes require more advanced methods for optimally provoking adaptation (Myslinski, 2003).
CONCENTRATED LOADING
Siff (2000) presented 3 potential contributing reasons why concurrent loading is sub-optimal for elite athletes:
It is in this scenario that a concentrated loading scheme may be utilized. Here, a concentrated loading influence is applied to the body with a high volume of unidirectional loading for the given primary emphasis (Siff, 2000). During the training block, all previously targeted traits are retained with maintenance loads. The duration of each training block is dependant upon individual sport demands, but for the purpose of this paper may be operationally defined as a period of 3-6 weeks. It would certainly not be unreasonable to construct a training block upwards of 2-months in duration, given the demands of acquiring sport form require such a duration. Figures 6 and 7 illustrate an adapted concentrated loading scheme during 2 mesocycles, respectively.
Training utilizing the repetitive method is the primary focus during the first mesocycle. As such, it yields the largest contribution to sport form following a brief unloading period. Note that maximal effort and dynamic effort are maintained with maintenance loading. The training focus is shifted to maximal effort. In addition, dynamic effort receives more training focus than repetitive effort. The large repetitive effort training effect from the first mesocycle is maintained and built upon via the training effect of maximal effort. This sequencing of training effects functions to further contribute to sport form.
CONCLUSION
Understanding the cumulative effect of stress and fatigue, as well as the beneficial after-effect of fitness, is necessary when programming the sequencing of training. Although certainly not perfect, the GAS and Fitness-Fatigue models can serve to facilitate this understanding. It is absolutely essential that fitness be maximized while simultaneously managing the accumulation of fatigue in order to optimally achieve, what should be, ever-growing levels of sport form.
References
Bannister, E.W. (1991). Modeling elite athletic performance, In: J.D. MacDougall, H.A. Wenger, and H.J. Green, eds. Physiological Testing of the High Performance Athlete. Champaign, IL: Human Kinetics.
Chiu, L.Z.F., Fry, A.C., Weiss, L.W., Schilling, B.K., Brown, L.E., and S.L. Smith. Post-activation potentiation response in athletic and recreationally trained individuals. Journal of Strength and Conditioning Research, 17(4), 671-677.
Chiu, L.Z.F., and Barnes, J.L. (2003). The Fitness Fatigue Model Revisited: Implications for Planning Short- and Long-Term Training. Strength and Conditioning Journal. 25(6), 42-51. Selye, H. (1978). The Stress of Life. (2nd ed). New York: McGraw Hill.
Dyachkov, V.M. (1964). The perfection of the athletes’ physical preparation. In: A.P. Bondarchuk. Relationships Between Technical Training and Physical Training. (B. Penner, Trans). Fitness and Sports Review International. Escondido, CA: Sports training, Inc. 1994:29:2.
Fry, A.C. (2004). The Role of Resistance Exercise Intensity on Muscle Fiber Adaptations. Sports Medicine, 34(10), 663-679.
Fry, A.C. (1998). The role of training intensity in resistance exercise overtraining and overreaching. In: R.B Kreider, A.C. Fry, and M.L. O’Toole, eds. Overtraining in Sport. Champaign, IL: Human Kinetics. Zatsiorsky, V.M. (1995). Science and Practice of Strength Training. Champaign, IL: Human Kinetics.
Hakkinen, K. (1995). Neuromuscular fatigue and recovery in women at different ages during heavy resistance loading. Electromyography and Clinical Neurophysiology, 35(7), 403-413.
Linnamo, V., Newton, R.W., Hakkinen, K., Komi, P.V., Davie, A., McGuigan, M., and Triplett-McBride, T. (2000). Neuromuscular responses to explosive and heavy resistance loading. Journal of Electromyography and Kinesiology. 10, 417-424.
Myslinski, T. (2003). The Development of the Russian Conjugate Sequence System. Unpublished Masters Thesis. EliteFTS.com.
Sale, D.G. (1988). Neural Adaptation to Resistance Training. Medicine and Science in Sports and Exercise, 20(5), S135-45.
Siff, M.C. (2000). Supertraining. (4th ed.). Denver, CO.
Verkhoshansky, Y.V. (1977). Fundamentals of Special Strength Training in Sport. Moscow: Fizkultura I Sport Publishers.