Training programs (TP) should be well structured and respecting all existing variables around the training (ACSM, 2009). An important variable is the choice of exercises that will be part of the training session, and are divided into single joint and multi-joint. The single joint exercises are known to utilize only one joint to move, as well as a muscle or muscle group. As for the multi-joint, also known as compound exercises, use more than one joint to perform the task, but also more than one muscle group.
In the case of multi-joint exercise, using various muscle groups, the function is divided between the major muscle group used for the movement (agonist muscle) and auxiliaries (synergist muscles). As an example we can take the bench press exercise, where the pectoral muscle group is the main movement of the agent and shoulder and triceps assist in the movement.
Based on this information, it can be suggested that the large muscle groups is the main function in multi-joint exercises while smaller form an auxiliary role. Although this reasoning, to achieve full activation of the smaller muscles, it would take single joint exercises specific (GENTIL et al., 2013).
Even with the statement of some studies that the large muscle groups are more activated than small groups in multi-joint exercises (GENTIL et al, 2007;.. BRENNECKE et al 2009), there are controversies. Other studies show that the smaller muscle groups have similar activation, or greater than the large groups (CLEMONS & AARON 1997; WELSCH et al. 2005).
Sympathy for single joint exercises also of the greater ease in learning compared to multi-joint. Some authors suggest that hypertrophy occurs more quickly when simple exercises are used, according to the authors, the beginning of training with multi-joint exercises, learning and coordination are predominant (Rutherford and Jones (1986) and Chilibeck et al. (1998).
Even with the statement of some studies that the large muscle groups are more activated than small groups in multi-joint exercises (Gentil et al, 2007;.. BRENNECKE et al 2009), there are controversies. Other studies show that the smaller muscle groups have similar activation, or greater than the large groups (Clemons & AARON 1997; Welsch et al., 2005).
Sympathy for single joint exercises also of the greater ease in learning compared to multi-joint. Some authors suggest that hypertrophy occurs more quickly when simple exercises are used, according to the authors, the beginning of training with multi-joint exercises, learning and coordination are predominant (Rutherford and Jones (1986) and Chilibeck et al. (1998).
Rogers et al. (2000), made the comparison between a training program composed only of multi-joint exercises and other training program was made up of both multi-joint exercises as additional single joint. The authors found no significant differences between groups with respect to strength and muscle circumference, which made them question the need for such exercises.
Seeking answers and a new analysis about the importance of simple exercises for muscle activation, Gentil et al. (2013) compared protocol only with compound exercises and another group with compounds and simple. No differences were found between groups both in muscle activation as for arm circumference.
We could conclude that the simple or single joint exercises are not required in training programs, however, cite that found no significant differences with respect to muscle activation, and, authors have reported in their studies no relationship between muscle activation and muscle damage, that would have a possible relationship with hypertrophy (PRIOR et al. (2001) e TAKAHASHI et al. (1994).
Suggestions
The findings of the studies may be of interest to people looking for a training session in less time, with a view to the possibility of similar results with less exercise.
Simple workouts do not provide negative results, however, their use may be interesting for a variety of tasks during the training session.
Despite the previous suggestion, look for new studies in order to give an opinion about this need, because, no study using only simple exercises are designed.
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