The traditional training with weights (TPT) is a widely used method for improving physical fitness, increased muscle strength, hypertrophy, strength and power. Recently has gained ground as a possibility in weight control (balance between intake and caloric expenditure). In order to achieve the goals set out by the student, the professional needs to suit a number of variables, as follows, series number and repetitions, training intensity, speed of execution, selection and order of the exercises and the rest interval (ACSM, 2009; BIRD, TAPENNING e MARINO, 2005).

       Have the circuit training (CT), characterized by performing a sequence of exercises with interval only when the execution of a series in each “station”. Studies have reported that TC benefits the cardiorespiratory fitness, physical fitness, muscle strength, coordination and alter body composition (JACOBS et al., 2001; ALCARAZ, SANCHEZ-LORENTE and BLAZEVICH, 2008).

     Some studies have found a higher energy expenditure in the method in circuit compared to weight training, however, the evaluation was performed by the total work in the training session and not matching the time and the workload between them, and not analyzing the energy expenditure anaerobic, thus making questionable results (ELLIOTT et al, 1992;. PICHON et al., 1996). When we seek to calculate the grounded spent on work done, there is a greater energy expenditure training with weights even with lower total work.

     Aniceto et al. (2013) developed a comparative study between weight training and circuit training where using volunteer subjects between 18 and 30 years, analyzing the aerobic energy expenditure, anaerobic and total. The researchers found similar basal metabolic values, therefore, the groups came out of the same level. The results showed a greater anaerobic energy expenditure in PD and in most aerobic TC, to total energy expenditure, there was no significant difference between the methods.

      The same study found higher lactate produced by the PD when compared to CT, due to different pattern of fiber recruitment for the task. It is possible that the lactate production in the circuit produced by type II fibers was reduced due to increased lactate removal by type I fibers, as may have been influenced by an increase in blood flow (Know muscle fiber types).

     The aerobic energy expenditure in the range of the series is the moment of greatest energy consumption due to ATP resynthesis for following the activity, it is through the consumption of excessive post exercise oxygen (EPOC). In the recovery period the energy obtained from the almost entirely by aerobic pathways, requiring substrates such as lactate and fat (SCOTT, 2011). Due to increased lactate concentration, PT appears to be more likely in the range energy expenditure.

Apparently there is no difference in energy expenditure between the circuit and method for training with traditional weights, suggesting that both can be used for the purpose of optimizing the energy consumption. Weight training has the advantage due to its improved capacity in anaerobic metabolism, which can improve long-term results.

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