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Performing multiple sets with the heaviest weight that is lifted in a particular exercise during a given training session is a very common training practice. In contrast, many athletes warm up to a maximum weight for the day and either end their training on that exercise for the day, or reduce the weight to perform a final "warm down" set or sets. Surprisingly, in today’s weight training circles, there is a rather heated debate going on between the advocates of performing one heavy set of each exercise in a particular workout and those who believe in performing multiple sets with ones top weight of the day (and performing lots of sets per exercise overall). Naturally, there are many trainers who take a position somewhere in between these extreme positions. Examining this issue in some detail can help to clear up much of the confusion that exists regarding this issue, because much of the debate takes place because the theorists in each school are arguing from different contexts. They would have far less to disagree about if they agreed on some ground rules for their discussions.
At one end of the one set versus multiple set spectrum there are a number of influential advocates of what is often termed the "one set to failure" school of training (e.g., Mike Mentzer and Arthur Jones). Under this system, the trainee performs one or two warm-up sets and then attacks the heaviest set of the day. With that weight, the athlete continues to perform repetitions until he or she actually fails to perform a repetition; many advocates of this system recommend doing some "forced" reps (reps that are performed with minimal assistance from a partner once the point of failure has been reached with normal reps) and/or some eccentric contractions after failure occurs with regular reps.
The one set to failure theorists argue that the training stimulus derived from one all out set will be sufficient to foster continuing improvement in a muscle's strength and/or size and that any additional sets performed, while providing no further stimulus for the body to improve (i.e., it has already been stimulated to the maximum by the first set) will actually have a detrimental effect on the body caused by overwork.
At the other end of the spectrum are those who recommend performing several warm-up sets and then several sets with the heaviest weight to be lifted for the day (some advocate the use of weights that are challenging for the number of reps performed as the athlete warms up—at least after the first set or two, in a "pyramiding" approach—described later in this chapter). These theorists believe that an athlete can only stimulate a maximal training effect with multiple sets.
To the surprise of some, advocates of each approach (and many that are in between the extremes) have had great success in some cases and a lesser degree of success in others. What can explain this apparent contradiction?
To begin with, there are no contradictions. Whenever one encounters what appears to be a contradiction it is appropriate to check the premises that are leading to the apparent contradiction. In those premises, and/or the reasoning from them, one will find a flaw that has lead to the apparent contradiction.
In this case, many of the advocates of each side of the one set/multiple set controversy overlook important differences in their premises. For example, when each side talks about the optimizing the training effect they often fail to recognize that any training effect is multidimensional. You can’t simply train for increased muscle size without influencing other capabilities of the organism, such as its contractile capabilities, its ability to recruit muscle fibers and the strength of its connective tissue. To say that one system has "the" optimal training effect fails to address the questions "Effect on what?" and "With what affect or cost to other capabilities?"
For instance, a one set to failure bout of exercise may create a training stimulus, but several sets performed in such a way may create an ever greater training stimulus. However, if the performance of several sets damages so much muscle tissue that the body will not be able to recover from the effort for an extended period of time, the benefit of the extra training stimulus may be counterbalanced by the lack of an ability to recover from the training session. However, if an athlete needs to have the capability of performing several maximal sets in competition, the performance of one set during training may not generate a sufficient training stimulus for the athlete to be optimally prepared for the demands of a competition.
So how does one address the one set/ multiple set dilemma? One must look at the full expanse of what one is trying to accomplish in training—in our case training for weightlifting competition.
First, there is now scientific evidence that more muscle fibers are activated on a maximum set of five reps than on a maximum single. From this it follows that a maximum set of high reps is more likely to stimulate a maximal training effect than a maximum single. Since weightlifters need to perform relatively low reps in training (and especially in competition) they will typically need to employ more sets to achieve their ends than someone who is performing five, ten or twenty reps in a set.
Second, it is not clear that one set to failure does provide the optimal training stimulus for a give athlete. Repeating sets undoubtedly increases the training stimulus and athletes vary in their ability to recover from a training session. Those differences in recovery rates suggest that some athletes may benefit from a greater training stimulus (or a greater frequency of administering the same stimulus) than other athletes. Obviously, there is a point where more training does not increase the training stimulus (the body is simply as stimulated as it can be by a given bout of exercise).
Third, the mental and emotional effort of performing a truly maximal set may be so much for some athletes that training to failure in every workout is simply wears them down over time. Such athletes may benefit from performing multiple sets with a lesser load (which will provide a training stimulus without subjecting the athlete to too great a mental and emotional strain—another important training concept that I learned primarily from Mark Gilman).
It is clear that performing too many sets, particularly if they are done to absolute failure at every workout, represents a waste of time that will eventually lead to overtraining.
For purposes of weightlifting training, multiple sets can help to develop skill in recruiting muscle fibers for all out efforts, and this skill is an important component of strength development. Just as massed study cannot replace properly spaced study periods for purposes of long term retention of learned material, one set cannot duplicate multiple sets in terms of the learning process that the latter entails. This is particularly true of complex movements like snatches and C&J’s, where skill at the overall movement as well as in exerting force is an important asset to the lifter.
Another consideration in the training of weightlifters is that multiple sets build the endurance needed for an athlete to withstand the rigors of competition. Weightlifting is an anaerobic activity requiring little cardiovascular fitness, but a competitive weightlifter must have the ability to perform maximum efforts over a period of hours (during much of which the athlete may be resting and handling sub-maximum weights). Performing multiple sets in training can help to develop this ability.
Still another consideration is that having both the one set to failure and multiple sub-maximal set approaches in ones training arsenal permits the athlete to go with the flow of the body's natural wisdom and cycles. There are some days when the lifter simply does not feel up to an all out effort. Nevertheless a lifter can have a very productive workout by handling lighter weights and doing multiple sets.
Finally, the trainee can train several aspects of a muscle's adaptive capacity by performing several different kinds of sets in the same workout (e.g., performing both high and low reps). This is obviously impossible without multiple sets.
How many sets should be performed for optimal strength gains? At least four variables influence the answer to this question. The first variable is that of intensity. The more intense an effort in a given set, the smaller is the number of sets that can be performed with the same intensity. An absolutely all out effort that results in a personal record may be impossible to duplicate in the same workout (and it is probably unproductive to try to do so).
The second variable is that of the number of reps performed in the set. Single efforts, no matter how intense, can nearly always be duplicated in subsequent sets (except perhaps the effort to attain a personal record that requires an athlete's complete psychological, emotional and physical reserves). Higher reps exhaust the athlete more completely and make repeated sets at the same intensity almost impossible. An all out set of twenty reps is a hard act to follow.
It should be noted that, as a group, the Bulgarians are at the extreme edge of those who believe that multiple maximum sets are beneficial. One of the reasons is that they train on singles, which permits more sets to be performed than if sets with higher reps are employed.
As a sort of rule of thumb, you often see athletes performing as many as five to ten singles with a weight that is difficult but not an all out maximum in training. Athletes who perform doubles generally perform from five to eight sets. When the reps rise to three, athletes rarely perform more than six sets, and three to five sets is closer to the norm. When reps rise into the four-to-six range, athletes perform as few as one and as many as five or six sets, but three sets is probably the median load handled. Naturally, all of the above are a function of the proximity of the load to the athlete’s maximum. The closer the load to that maximum, the lower the number of sets is likely to be.
The third variable is the muscle groups involved in the effort. Certain muscle groups appear to recover more quickly from set to set than others. It is generally more difficult to perform repeated sets with maximal effort in the squat than in the military press. In addition, multiple maximal sets in the squat will fatigue the body far more overall than multiple sets of presses.
The last issue is the degree and length of muscle tension developed during the repetitions of a set affect the number of sets in which maximal efforts can be performed. Generally, the greater the tension that is developed in the muscle and the longer it is maintained, the more difficult it is to repeat sets at the same level of performance. It is easier, at least on a physical level, to repeat an all out effort in the snatch than in the squat. This is particularly true if the squats are performed in a slow fashion in both the ascent and the descent.
Only by considering all of these factors in combination can an athlete or coach estimate the training stimulus that will be generated by a given bout of exercise. By balancing these factors a athlete can generate improvements with multiple or single heavy sets.