This is an excerpt from Optimizing Strength Training by William Kraemer & Steven Fleck.
Muscle Soreness, Tissue Damage, and Recovery
Two major factors create muscle soreness. First is the acute muscle damage created by the loading of the muscle fibers themselves, predominantly the eccentric loading stress. The higher the eccentric load, the greater the stress. Remember that when a person is at his or her maximal dynamic concentric strength level, it represents only about 80% of eccentric maximal strength. As the speed of eccentric movement increases, the forces on the muscle increase. The second factor in muscle damage arises from the chemical damage that follows the mechanical events and hypoxia of the tissue when exercising under anaerobic conditions. This can cause continuous tissue breakdown, soreness, and delays in recovery for up to 10 days. This is typically called delayed-onset muscle soreness, or DOMS, and normally peaks at 24 to 48 hours postexercise. The greater the DOMS, the longer the delay in the ability to perform optimal training because rest is needed in order to allow the muscle to repair the damage caused by the training.
The first rule in the recovery from a resistance exercise workout is proper planning and refraining from doing too much too soon. Once injury or significant muscle damage occurs, a lifter has to deal with it. So the best strategy for avoiding excessive DOMS is sound planning of the training program. Many common treatments (e.g., ice, hydrotherapy, massage) have not been effective in treating DOMS. However, compression has been shown to limit the amount of swelling and loss of force production over a 24- to 72-hour postexercise time frame (Kraemer et al., 2001). Therefore the best treatment is an ounce of prevention. This resides in proper program progression in a nonlinear format using part of the mesocycle as a preparation phase as well as a gradual progression to any very heavy, power, or heavy eccentric training (see Base Program, chapter 5).
With a nonlinear program a trainee cannot jump right into the heavier loading schemes, which by their nature also have a high eccentric component and therefore can cause significant muscle damage. Muscle damage will be more dramatic in beginners or in those who have taken a long break from training. In these situations a type of general preparation phase is necessary before the heavier training zones or cycles. This means that the first 4 weeks of a mesocycle's workouts are in the very light-intensity to moderate-intensity range, the volume of exercise starts with one set and progresses to 2 or 3, rest periods last from 2 to 4 minutes, and exercise technique is stressed. Each time a new exercise is added or the resistance is increased, a trainer or coach needs to check the exercise technique. Remember that toleration of the exercise stress is vital to optimal progress. With prior exposure to moderately heavy resistances, a natural protection against eccentric damage will be developed. Essentially this is a base program.
No heavy protocols should be done in the early phases of a training program. Use of eccentric-only workout protocols is not typical in the nonlinear program approach; these protocols would be used only in some advanced training techniques typically targeted at breaking through a plateau in performance. However, the efficacy of this approach has not been validated by scientific studies.
Resistance training has been shown to be effective across every age group, including seniors. Nevertheless, as a person grows older, changes in the physiological system occur that make the person less adaptive to an exercise stimulus. As a person ages, reductions in water content in cells, hormonal releases, and other physiological functions occur. In other words, the adaptive processes that allow a person to repair and remodel tissues are not as robust as they were in younger years. It is very common to hear an older person say, "I used to be able to get in shape in a matter of weeks, but now it seems to take months." The perception of a delayed response to exercise training is simply a function of aging.
One of the major considerations when training as we age is the toleration of a particular workout. Individuals over the age of 50 many times have joint soreness and muscle soreness in response to heavy and very heavy workouts. Therefore, the frequency for these particular workout intensities must be carefully prescribed. As a general rule, as a person ages the frequency of such high intensities over the course of a mesocycle should be reduced. In addition, training zones may be adapted for older lifters. In other words, a very heavy day may mean a 6- to 8RM zone, a heavy day could be a 9- to 11RM zone, a moderate day a 12- to 14RM zone, and a light day a 15- to 17RM zone. It has been shown that older men and women can tolerate typical heavy-loading days, but the recovery and responses to the workouts need to be carefully monitored for everyone, especially in people over the age of 50 years. If joint soreness or stiffness occurs, then you must reduce the frequency of heavy-loading days or redefine the RM training zones. The latter should definitely occur if symptoms persist.
Another effect of aging is the inability to tolerate decreases in muscle and blood pH or challenges to the buffering capacity of the body in dealing with acidity. When reducing lengths of rest periods, pay a great deal of attention to any adverse symptoms (e.g., nausea, dizziness) in all trainees, but especially in individuals over the age of 50 due to a reduction in buffering capacity. If you reduce lengths of rest periods between sets and exercises during a program for individuals over the age of 50, do so slowly over a mesocycle.
Finally, older individuals need to be very careful when completing a set to failure. The natural breath holding (Valsalva maneuver) that occurs can cause undue increases in blood pressure. This is of particular concern in individuals who have a history of cardiac problems, a family history of cardiac problems, or unstable left-ventricular function. In general, older lifters should avoid or at least minimize the use of the Valsalva maneuver. Another precaution is that the RM zone indicates repetitions that are typically not done to absolute failure, but rather with a keen perception that more than the prescribed repetitions cannot be performed. Therefore, inform each lifter that an RM zone is a load that typically allows a person to complete a set without going to complete failure. Teach each lifter to breathe properly: Exhale during the concentric (lifting or pushing) phase and inhale during the eccentric (lowering or releasing) phase. While failure in a repetition may occur, breathing during each repetition needs to occur and breath holding should be eliminated. Going to failure will cause greater joint compression and potential joint soreness due to shearing forces. The loads for each RM zone should be found without going to complete failure in a repetition, as one can typically know what a resistance will allow for a repetition in a 3RM zone. As is standard, older individuals (over the age of 45 years) should have a physician's approval to engage in a vigorous exercise program.
When designing a resistance training program for children, all the safety factors normally associated with an adult program apply. However, there are several other considerations that uniquely apply to children. One of these factors is the possibility of damage to the epiphyseal plates, or growth plates, of bones caused by the lifting of heavy resistances by children whose skeletal systems have not matured. Although this type of injury can occur, it is very rare and typically occurs when children attempt to lift close to 1RM resistances in an unsupervised setting. To prevent damage to epiphyseal plates, children should not lift resistances heavier than 6RM. When using the nonlinear periodization training approach with children, this simply means that the training zones need to be adjusted accordingly. For example, for children, heavy, moderate, and light training zones might be 6- to 8RM, 8- to 12RM, and 12- to 15RM, respectively. In general, a progression in training occurs with age as many young men and women start to enter adult programs at 15 or 16 years of age depending upon their prior training experience. Extensive guidelines for young athletes at different ages have been presented in our book Strength Training for Young Athletes, Second Edition, (see Kraemer & Fleck, 2005).
Another consideration when you are training children is establishing realistic training goals. Here one major difference between an adult's program goals and the goals for children is that, in children, it is unrealistic to expect large gains in muscle size. After a child has reached puberty, gains in muscle size become a more realistic goal. Other training goals, such as increased strength and injury prevention when participating in other sporting activities, are achievable for children.
The following are other considerations that uniquely apply to children and should be considered when children perform weight training:
• Is the child psychologically and physically ready to participate in weight training?
• Do the child and the weight training supervisor understand proper lifting techniques for each exercise being performed?
• Do the child and the weight training supervisor understand proper safety and spotting techniques for each exercise being performed?
• If resistance training machines are used, does each piece of equipment fit the child's body?
• Does the child have a balanced physical exercise program that includes not only resistance training but also cardiorespiratory and flexibility training?
• Have any fears or misconceptions the child has about weight training been discussed with the child and dispelled?
• Is there a sufficient number of adult supervisors to ensure the practice of safe lifting habits, proper exercise technique, and all safety precautions?
All of these factors and others that uniquely apply to resistance training for children have been discussed in great detail (Kraemer & Fleck, 2005). The bottom line is that children can safely perform resistance training, and resistance training can be effective in bringing about strength and fitness gains in children, but some program design and performance considerations are unique to this age group.
When designing a resistance training program for women, including a nonlinear program, on the surface there may seem as though there should be a lot of differences between a program designed for males and a program for females. But in reality there are very few differences between programs designed for men and those designed for women. Skeletal muscle, whether it is in a male or a female, responds to a resistance training program with similar adaptations.
Generally adult males are stronger than adult females. However, much of this difference is because adult males are simply larger and have greater fat-free mass than their female counterparts. If maximal lower-body strength (1RM) is equated relative to body weight, males and females are very similar, and the similarity increases if maximal strength is expressed relative to fat-free mass or muscle mass. In fact, some studies report females to be stronger than males when lower-body maximal strength is expressed relative to fat-free mass (for review, see Fleck & Kraemer, 2004). This, however, is probably because women have a greater percentage of their fat-free mass in their lower bodies than their male counterparts. This means that men have a higher percentage of their fat-free mass in their upper bodies compared to women and so have stronger upper bodies. Although total fat-free mass and distribution of fat-free mass may explain strength differences between the sexes, it does not mean that male muscle and female muscle respond differently to training. This will, however, affect the training resistance required in order to stay within a training zone. This simply means that males, especially for upper-body exercises, will need a heavier resistance for any particular training zone. It does not mean that women need to use different training zones when using a nonlinear periodization training program. In fact, the majority of long-term training studies using a nonlinear periodization training model have had women as participants (for review, see Fleck & Kraemer, 2004).
The differences between the genders in terms of distribution of fat-free mass (i.e., men have a greater percentage of their fat-free mass in their upper bodies) does, however, lead to a possible difference in resistance training programs between the sexes. Upper-body strength and power are very important for success in many sports and activities. With a smaller percentage of fat-free mass in their upper bodies, women are at a disadvantage when performing sports or activities dependent on upper-body strength and power. So to optimize physical performance, upper-body strength and power exercises may be emphasized in a training program slightly more in women than in men. The need for upper-body strength and power to optimize physical performance can be demonstrated quite clearly even in activities that you might not think are dependent on upper-body strength. For example, many people, including women, can increase 1RM squat strength by performing only upper-body training. Here the increase in squat 1RM is because the lower body is already capable of performing the squat with more resistance. However, the ability for the lower body to express its maximal strength is limited by the upper body's ability to support more weight in the squat. Thus for female athletes who are dependent on upper-body strength and power for success, emphasizing upper-body exercises may be appropriate. This can be accomplished by adding one or two more exercises for the upper body or, after the individual is moderately trained, adding one set to some of the upper-body exercises already included in the program.
Generally women increase their fat-free mass or muscle mass to a lesser degree in both absolute terms (pounds or kilograms) and relative terms (percentage of increase) when performing the same weight training program as males. Again, this does not mean that the muscle of males and females responds differently to training. It merely means that when establishing a training goal concerning increases in fat-free mass or muscle mass, the goal should be lower in women than in men.
So there are relatively very few differences between nonlinear periodization programs designed for men and for women. None of the differences causes a significant change in the total design of the program. The differences between men's and women's responses to resistance training have been more extensively discussed (Fleck & Kraemer 2004).
A well-kept training log is vital in monitoring training progress and in making modifications to the training sessions in a nonlinear resistance training program. Use of the nonlinear program can be applied in almost any situation, including the training of older adults, children, and women. Optimal sequencing, correct exercise choices, monitoring recovery, and appropriate training goals are the keys to an effective nonlinear program. Reductions in the boredom brought about by a resistance training program as well as a higher quality of training will be realized with the nonlinear approach. The variations possible in nonlinear programming make it ideal for all athletes as well as average people interested in health and fitness goals. Understanding how to evaluate effectiveness of programs and determine the amount of fatigue is also vital for making logical and effective changes in the program used for each mesocycle.
This is an excerpt from Optimizing Strength Training.