Periodization Principles for Strength

by Tudor O. Bompa, PhD


    Training guidelines fulfill a given training goal. Proper application ensures superior organization with the fewest errors. The principle of progressive increase of load in training leads to better adaptation and improved strength gains.

 

The Five Basic Laws of Strength Training

    Any strength training program should apply the five basic laws of training to ensure adaptation, keeping athletes free of injury. This is especially important for young athletes.

 

Key Words

    •    Amortization Phase: The eccentric or yielding phase of an activity; also called the "shock-absorption phase."

    •    Hormone: A discrete chemical substance secreted into the body by an endocrine gland that has a specific effect on the activities of other cells, tissues and organs.

    •    Innervate: To stimulate the transmission of nervous energy to a muscle.

    •    Testosterone: The male sex hormone; it produces masculinizing properties


Law Number One: Develop Joint Flexibility
    Most strength training exercises use the entire range of motion of major joints, especially the knees, ankles, and hips. Good joint flexibility prevents strain and pain around the knees, elbows, and other joints. Ankle flexibility (plantar flexion, or bringing the toes toward the calf) should be a major concern for all athletes, especially beginners. Good flexibility prevents stress injuries. Athletes must start developing ankle flexibility during prepubescence and pubescence so that in the latter stages of athletic development it need only be maintained.

Law Number Two: Develop Tendon Strength
    Muscle strength improves faster than tendon and ligament strength. Misuse and faulty utilization of the principle of specificity, or lack of a long-term vision, causes many training specialists and coaches to overlook overall strengthening of ligaments. Tendons and ligaments grow strong through anatomical adaptation. Without proper anatomical adaptation, vigorous strength training can injure the tendons and ligaments. Training tendons and ligaments causes them to enlarge in diameter, increasing their ability to withstand tension and tearing.

Law Number Three: Develop Core Strength
    The arms and legs are only as strong as the trunk. A poorly developed trunk is a weak support for hard-working limbs. Strength training programs should first strengthen the core muscles before focusing on the arms and legs. The core muscles act as shock absorbers for jumps, rebounds, or plyometric exercises; stabilize the body; and represent a link, or transmitter, between the legs and arms. Weak core muscles fail in these essential roles, limiting the athlete's ability to perform. Most of these muscles seem to be dominated by ST fibers because of their supporting role to the arms and legs. They contract constantly, but not necessarily dynamically, to create a solid base of support for the actions of other muscle groups of the body.
    Many people complain of low back problems yet do little to correct them. The best protection against low back problems is well-developed back and abdominal muscles. Coaches and athletes must pay more attention to this area of the body.
    Abdominal Muscles. The abdominal and back muscles surround the core area of the body with a tight and powerful support structure of muscle bundles running in different directions. Since many athletes have weak abdominal muscles in relation to their backs, general and specific abdominal muscle training is recommended. The rectus abdominis runs vertically and pulls the trunk forward when the legs are fixed, as in sit-ups, maintaining good posture. If the abdominal muscles are poorly developed, the hips tilt forward and lordosis or a swayback develops at the lumbar area of the spine because the low back muscles are much stronger.
    The internal and external obliques help the rectus abdominis bend the trunk forward and perform all twisting, lateral bending, and trunk-rotating motions. They help an athlete recover from a fall in many sports and perform many actions in boxing, wrestling, and the martial arts. The anterior and lateral abdominal muscles perform delicate, precise trunk movements. These large muscles run vertically, diagonally, and horizontally.
    Isolating the abdominal muscles requires an exercise that bends the spine but not the hips. Exercises that flex the hips are performed by the iliopsoas (a powerful hip flexor) and to a lesser extent by the abdominals. Sit-ups are the most popular abdominal exercise. The best sit-up position is lying on the back with the calves resting on a chair or bench. This position isolates the abdominals since the hips are already bent.
    Back Muscles. The back muscles, including the deep back muscles of the vertebral column, are responsible for many movements such as back extension and extending and rotating the trunk. The trunk acts as the transmitter and supporter of most arm and leg actions. The vertebral column also plays an essential role as a shock absorber for landing and takeoff actions.

    Excessive, uneven stress on the spine or sudden movement while in an unfavorable position may lead to back problems. For athletes, back complaints may be due to wear and tear caused by improper positioning or forward tilting of the body. Disc pressure varies according to body position relative to external stress. Stress on the spine increases during lifting in standing or seated positions or when the upper body swings, such as in upright rowing or elbow flexion. Sitting produces greater disc pressure than standing; the least stress occurs when the body is prone (such as in bench presses or pulls). In many exercises that use the back muscles, abdominal muscles contract isometrically, stabilizing the body.
    The Iliopsoas. The iliopsoas is an essential muscle for hip flexion and running. Though not large, it is the most powerful hip flexor, responsible for swinging the legs forward during running and jumping. Sports performed on the ground require a well-developed iliopsoas. Exercises such as leg and knee lifts against resistance are key to training this important muscle.

Law Number Four: Develop the Stabilizers
    Prime movers work more efficiently with strong stabilizer or fixator muscles. Stabilizers contract, primarily isometrically, to immobilize a limb so that another part of the body can act. For example, the shoulders are immobilized during elbow flexion, and the abdominals serve as fixators when the arms throw a ball. In rowing, when the trunk muscles act as stabilizers, the trunk transmits leg power to the arms, which then drive the blade through the water. A weak stabilizer inhibits the contracting capacity of the prime movers.
    Improperly developed stabilizers may hamper the activity of major muscles. When under chronic stress, the stabilizers spasm, restraining the prime movers and lessening athletic effectiveness. At the shoulders, supra- and infraspinatus muscles rotate the arm. The simplest, most effective exercise to strengthen these two muscles is to rotate the arm with a partner tightly holding the fist. The resistance provided by the partner stimulates the two muscles stabilizing the shoulder. At the hips, the piriformis muscle performs outward rotation. To strengthen this muscle, the athlete should stand with knees locked. While a partner provides resistance by holding one foot in place with both hands, the athlete performs inward-outward leg rotations. At the knees, the popliteus muscle rotates the calf. A simple exercise is for the athlete to sit on a table or desk with the knees flexed. A partner provides resistance by holding the foot as the athlete performs inward-outward rotations of the calf.
    Stabilizers also contract isometrically, immobilizing one part of the limb and allowing the other to move. Stabilizers can also monitor the state of the long bones' interactions in joints and sense potential injury resulting from improper technique, inappropriate strength, or spasms produced by poor stress management. If one of these three conditions occurs, the stabilizers restrain the activity of the prime movers, avoiding strain and injuries.
    Unfortunately, few coaches take the time to strengthen the stabilizers. Time should be set aside during the transition and preparatory periods, especially the anatomical adaptation phase for stabilizer training. The core muscles, rotators, and stabilizers should be developed using long-term progression (figure 3.1). A casual approach would be a disservice to the serious athlete.


Law Number Five: Train Movements, Not Individual Muscles
    Athletes should resist training muscles in isolation as in bodybuilding. The purpose of strength training in sports is to simulate sport skills. Athletic skills are multijoint movements occurring in a certain order, called a kinetic chain (movement chain). For instance, a takeoff to catch a ball has the following kinetic chain: hip extensions, then knee extensions, and finally ankle extensions, in which the feet apply force against the ground to lift the body.

    According to the principle of specificity, body position and limb angles should resemble those for the specific skills. When athletes train a movement, the muscles are integrated and strengthened to perform the action with more power. Therefore, athletes should not resort to weight training alone, but should broaden their training routines, incorporating medicine balls, rubber cords, shots, and plyometric equipment. Exercises performed with these instruments allow athletes to initiate skills more easily.

 

Principle of Progressive Increase of Load in Training

    According to Greek mythology, the first person to apply the principle of progressive increase of load was Milo of Croton. To become the world's strongest man, Milo started to lift and carry a calf every day. As the calf grew heavier, Milo grew stronger. By the time the calf was a full-grown bull, Milo was the world's strongest man thanks to long-term progression.
    Improved performance is a direct result of quality training. From the initiation stage to the elite performance stage, workload in training must increase gradually according to each athlete's physiological and psychological abilities. Physiologically, training gradually increases the body's functional efficiency, increasing its work capacity. Any dramatic increase in performance requires a long period of training and adaptation (Astrand & Rodahl, 1985). The body reacts physiologically and psychologically to the increased training load. Similarly, nervous reaction and functions, neuromuscular coordination, and psychological capacity to cope with stress also occur gradually. The entire process requires time and competent technical leadership.
    Several sports have a consistent training load throughout the year, called a standard load. Most team sports maintain 6 to12 hours of training per week for the entire year. Standard loading results in early improvements, followed by a plateau and then detraining during the competitive phase (figure 3.2). This may cause decreased performance during the late competitive phase, since the physiological basis of performance has decreased and prevent annual improvements. Only steady training load increments will produce superior adaptation and performance.
    The overload principle is another traditional strength training approach. Early proponents of this principle claimed strength and hypertrophy will increase only if muscles work at their maximum strength capacity against workloads greater than those normally encountered (Lange, 1919; Hellebrand & Houtz, 1956). Contemporary advocates suggest that the load in strength training should be increased throughout the program (Fox et al., 1989). As such, the curve of load increment constantly rises (figure 3.3).

 

    Proponents of overloading suggest two ways to increase strength: (1) brief maximum contractions resulting in high muscle activation; and (2) submaximum contractions to exhaustion, inducing hypertrophy. The latter approach is popular among bodybuilders; however, it is categorically impractical in athletics. Athletes cannot be expected to lift to exhaustion every day. Such physiological and psychological strain leads to fatigue, exhaustion, and overtraining. To be effective, a strength training program must follow the concept of Periodization of Strength, with specific goals for each phase leading up to the major competitions of the year.
    The step-type approach is more effective than overloading. The athlete's ability to tolerate heavy loads improves as the result of adaptation to stressors applied in strength training (Councilman, 1968; Harre, 1982). The step-type method requires a training load increase followed by an unloading phase during which the body adapts, regenerates, and prepares for a new increase. The frequency of the increase in training load must be determined by each individual's needs, rate of adaptation, and competitive calendar. An abrupt increase in training load may go beyond the athlete's capacity to adapt, affecting the physiological balance. The rate of the athlete's performance improvement determines training load increase. The faster the rate of performance improvement, the greater the training loads required for the athlete to keep up.
    The step-type approach (figure 3.4) does not mean steadily increasing the load in each training session through the arithmetic addition of equal quantities of work. A single training session is insufficient to cause visible body change. To achieve such adaptation, the same type of training loads must be repeated several times. Often training sessions of the same type are planned for an entire week, followed by an increase in the training load.
    In figure 3.4, let's say the horizontal line represents a week, or a microcycle, of training and that the load is increased on Monday. This increase fatigues the body since it is not accustomed to such stress. The body adjusts by Wednesday, adapts to the load over the next 2 days, and by Friday, the athlete feels stronger and capable of lifting heavier loads. Fatigue is followed by adaptation, then a physiological rebound or improvement. This new level is called a new ceiling of adaptation. By Monday, the athlete is physiologically and psychologically comfortable. The previous adaptation has been challenged so that constant improvements occur from step to step.
The third step in figure 3.4 is followed by a lower step, or unloading phase. A reduction in overall demand allows the body to regenerate. During regeneration, the athlete partially recovers from the fatigue accumulated in the first three steps, replenishes energy stores, and psychologically relaxes. The body accumulates new reserves in anticipation of further increases in training load. Training performance usually improves following the regeneration phase. The unloading phase represents the new lowest step for the next macrocycle. Since the body has adjusted to the previous loads, this new low step is of greater magnitude than the previous low, but is nearly equal to the medium one.


    The shorter the adaptation phase, the lower the height, or the amount of increase, in training load. A longer adaptation phase may permit a higher increase. Although training load increases in steps, the load curve for a training plan of longer duration has a wavy shape that represents the continuous increases and decreases in the training components (figure 3.5).

 

Variations of Step Loading

    Although the step-loading method is applicable to every sport and athlete, two variations are possible but must be applied carefully and with discretion.
    In reverse step loading (figure 3.6), the load decreases rather than increases from step to step. Some Eastern European weight lifters maintain that it is more specific to their physiological needs in that the highest loads are planned immediately following a cycle of low-intensity training. Reverse step loading has been used in weight lifting since the late 1960s but has not been accepted in any other sport. The reason is simple: The goal of strength training for sports is progressive adaptation-gradually increasing the athlete's training capabilities. Performance improvements are possible only when training capabilities have increased. Reverse loading should only be used during the peaking cycle prior to competition. Endurance improvements are much better achieved by step loading.


    The flat step loading pattern (figure 3.7), is appropriate for advanced athletes with strong strength training backgrounds. High-demand training is performed at the same level for three cycles, followed by a low-load, recovery week. The load is then increased to medium during the third and other macrocycles as the athlete adapts. The high-demand cycles must be applied in concert with other types of training. As such, the three cycles have to be of high demand for all elements-technical, tactical, speed, and endurance training. When planning a lower intensity cycle, all other elements must be of lower demand as well to facilitate relaxation and recovery.


    The dynamics of the loading pattern for a well-trained athlete are a function of the training phase and type of strength training sought. During the early part of the preparatory phase, the step loading pattern prevails, ensuring a better progression. The same loading pattern is suggested for athletes with 1 to 2 years' experience in strength training. For endurance sports, where the development of muscle endurance is the focus of specific strength training, and for athletes competing at or beyond the national level, the flat loading pattern is suggested (figure 3.8).

 

Principle of Variety

    Contemporary training requires many hours of work from the athlete. The volume and intensity of training are continuously increasing, and exercises are repeated numerous times. To reach high performance, the volume of training must surpass a threshold of 1,000 hours per year. Any athlete serious about training must dedicate 4 to 6 hours to strength training each week, in addition to technical, tactical, and other elements of general and specific conditioning.
    Under these conditions, boredom and monotony can become obstacles to motivation and improvement. The best way to overcome these obstacles is to incorporate as much variety as possible into training routines. Instructors and coaches have to be well versed in the area of strength training and know as many exercises as possible to ensure such variety. In addition to improving training response, variety has a positive effect on the psychological wellbeing of athletes. The following suggestions will help enrich your strength training program:

Principle of Individualization

    Contemporary training requires individualization. Each athlete must be treated according to individual ability, potential, and strength training background. Often coaches follow the training programs of successful athletes, disregarding their athlete's needs, experience, and abilities. Even worse, such programs are sometimes inserted into the training schedules of junior athletes. Young athletes are not ready, physiologically or psychologically, for such programs.
    Before designing a training program, analyze the athlete's training potential. Athletes equal in performance do not necessarily have the same work capacity. Individual work abilities are determined by several biological and psychological factors and must be considered in specifying the amount of work, the load, and the type of strength training. Training background also determines work capacity. Work demand should be based on experience. Even when athletes exhibit great improvement, coaches must still be cautious in estimating training load. When assigning athletes of different backgrounds and experiences to the same training group, coaches should not ignore individual characteristics and potential.
    Another factor is the athlete's rate of recovery. When planning and evaluating the content and stress of training, assess demanding factors apart from training. Be aware of the athlete's lifestyle and emotional involvements. School work or other activities can affect rate of recovery.
    Gender differences also require consideration. The total body strength of women is 63.5 percent that of men. Upper body strength in women is an average 55.8 percent that of men. Lower body difference is much less, averaging 71.9 percent (Laubach, 1976). Women tend to have lower hypertrophy levels than men, mostly because their testosterone level is 10 times lower (Wright, 1980). Female athletes can follow the same training programs as male athletes without worrying about excessive bulky muscles. Women can apply the same loading pattern, the same training methods, and follow similar planning without concern. Strength training is as beneficial for women as for men. In fact, strength gains for women occur at the same or an even greater rate (Wilmore et al., 1978). Strength training for women should be rigorously continuous, without long interruptions. Plyometric training should progress carefully over a longer period. Since women generally tend to be physically weaker than men, visible gains in future performance will come from improved and increased strength training.

 

Principle of Specificity

    To be effective and achieve greater adaptation, training must be designed to develop sport-specific strength, A strength training program and the selected training method(s) should consider the dominant energy system of the sport and the prime movers involved. Training specificity is also the most important mechanism for sport-specific neural adaptation.
    The dominant energy system in the sport should be carefully considered. For instance, muscle-endurance training is most appropriate for endurance sports like rowing, long-distance swimming, canoeing, or speed skating. Also consider the specific muscle groups involved (prime movers) and the movement patterns characteristic of the sport. Exercises should mimic the sport's key movement patterns or dominant skills. They must also improve the power of the prime movers. Normally, gains in power transfer to skill improvement.

 

Specificity vs. a Methodical Approach

    The principle of specificity sprang from the idea that the optimal strength training program must be specific. Mathews and Fox (1976) developed this theory into a principle of training. According to this principle, an exercise or type of training that is specific to the skills of a sport results in faster adaptation and yields faster performance improvement. Specificity should be applied only to advanced athletes during the competitive phase. Athletes perfect only the dominant strength in their selected sport.
    Misuse of specificity results in asymmetrical and inharmonious body development and neglects the antagonistic and stabilizer muscles. Misuse can also hamper the development of the prime movers and result in injuries. Overemphasizing specificity can result in narrow development of the muscles and one-sided, specialized muscle function. Compensation strength exercises should always be used in training, especially during the preparatory phase of the annual plan. These exercises balance the force of agonistic and antagonistic muscles.
    Although specificity is an important principle, its long-term application can result in stressful, boring programs, leading to overtraining, overuse injury, and sometimes burnout. Specificity is best applied at appropriate times in a program based on a methodical, long-term approach. Such a program should have three main phases (see figure 3.9).
    During general and multilateral strength training, all muscle groups, ligaments, and tendons are developed in anticipation of future heavy loads and specific training. Such an approach would likely lead to an injury-free career. This phase may last 2 to 4 years depending on the athlete's age and abilities. Throughout this phase, the coach needs to be patient. Overall multilateral development is a basic requirement for reaching a highly specialized level of training.
    After laying the foundation, the athlete begins the specialized training specific phase which will continue throughout his career. This is not a strength training program that addresses the specific needs of the sport through all phases of an annual training plan. Rather, this program includes Periodization of Strength, which always starts with a buildup or anatomical adaptation phase. Depending on the age of the athlete, this phase can last 2 to 3 years.
    The high-performance phase applies to athletes at the national and international level. During this stage, specificity prevails from the latter part of the preparatory phase through the competitive phase of the annual plan. This phase ends when the athlete stops competing.

 

Specificity of Exercises for Strength Training

    It is difficult to mimic the technical skill of a given sport in strength training, so coaches must try to imitate the dynamic structure of the skill as well as the spatial orientation, or the position of the body compared to the surrounding environment. Coaches should select exercises that align the body and limbs with the positions used to perform a skill.
    The angle between body parts or limbs influences how and which parts of a given muscle contract. Effective training of the prime movers requires familiarity with this aspect. For example, sit-ups are popular abdominal exercises; however, body position changes the difficulty as well as the segment of the muscle (rectus abdominis) contracted maximally.     Horizontal sit-ups involve mostly the upper part of the muscle. Inclined sit-ups primarily benefit the central section of the muscle, since the movement is performed with an almost full range of motion. If the trunk is fixed and the legs are lifted, the role of the abdominals decreases and the action is performed mostly by the hip flexors (iliopsoas muscle). The best position for activating the abdominals is one that immobilizes the hips so the trunk moves by contracting the rectus abdominis muscle (inclined position, or with the legs resting on a chair, bench, or against a wall).
    Similar concerns apply to the bench press. If the bench press is performed on a flat bench, the central parts of the pectorals, the triceps, and parts of the deltoid muscle benefit. If the same exercise is performed on an inclined bench, the upper parts of the pectorals fully contract. To stress the lower pectorals, athletes should place their heads at the lower end of an incline bench. The grip used for the bench press also affects the muscles involved. A wide grip mainly stresses the exterior part of the pectorals. A shoulder-width grip develops the inner part of the pectorals. A narrow grip activates mostly the deeper part of the pectorals and the triceps muscle.
    To achieve maximum training specificity, an exercise has to imitate the angle of the skill performed. For instance, the arm extensions used by shot putters and football linemen use the triceps muscles. A bodybuilder exercise to develop the triceps is elbow extensions either bent-over or in an erect position with the elbow above the shoulder. Such exercises isolate the triceps from the other muscles involved in shot putting or tackling (analytic method) and consequently are not very effective for these athletes. Incline bench presses at an angle of 30 to 35 degrees would be better, since the angle is similar to that used in these .sports. This exercise also works the other active muscles such as the pectorals and deltoids.

 

Specificity of Strength Exercises and the Need for Specific Adaptation

    In many cases, athletes and coaches rate the success of a strength training program based on the amount of muscle the athlete builds (hypertrophy). With the exception of football linemen, shot putters, and heavyweight boxers and wrestlers, constant increase in muscle size is not a desirable effect for most athletes. Power and speed sports, or sports with quick, explosive action (baseball, football, hockey, most track-and-field events, volleyball, etc.) rely on nervous system training that includes many power exercises and maximum loads (greater than 80 percent of 1RM) that result in neural adaptation (Enoka, 1996; Sale, 1986; Schmidtbleicher, 1992). Neural adaptation in strength training for most sports means increasing power and the speed of contraction without increasing muscle mass.
    To achieve higher neural adaptation, carefully select training methods and exercises. Researchers and international-class coaches share similar views about what represents the specificity of strength training. These views are summarized below.

FROM: PERIODIZATION Training for Sports -- Programs for peak strength