Regardless of your fitness level, your weight-training routine greatly influences your fitness outcomes. Seemingly minor differences between circuit- and strength-training cultivate different aspects of muscular health and should be evaluated. For instance, one targets endurance while the other does not. Understanding program variations enables you to know which program fits best with your specific personal fitness goals.
Measurable characteristics of muscular fitness include strength, endurance and size. Strength regulates maximal force production during a single contraction while endurance influences ability to repeat a sub-maximal contraction over time -- walking, jogging and jumping rope require muscular endurance. Traditional strength programs focus on maximal strength production while typical circuit training routines target muscular endurance at the expense of strength gains, as noted by the National Strength and Conditioning Association (NSCA).
Sets and Reps
Circuit training involves four to 12 exercise stations within each 20- to 50-minute session, as stated by the American Council on Exercise. According to ACE, weight-training circuits use large muscle groups first and require 10 to 20 repetitions per station. On the other hand, strength-training programs require up to five sets of one to eight repetitions, as defined by the NSCA. Due to increased repetition performance, circuit training enhances muscular endurance.
An inverse relationship exists between lifting load and repetitions performed. Circuit-training promotes high-repetition performance using weight-lifting loads of 50 to 70 percent maximal ability, according to ACE. Alternatively, strength training targets heavy lifting with loads of 80 to 100 percent maximal ability. Strength-training loads recruit greater percentages of muscle mass -- resulting in superior strength adaptations.
Rest between sets dictates subsequent set performance. Circuit training targets muscular endurance by employing short rest periods, of 20 to 30 seconds, between stations, or sets. Strength-training success requires maximal-effort lifting during each set. Therefore, strength-training programs use rest periods of two to five minutes between sets, as prescribed by the NSCA. Longer rest periods enable full muscular recovery while shorter periods do not.
ACE suggests circuit training for overall fitness benefits. In addition, circuit training provides a full-body workout in a short amount of time. However, the NSCA states, strength and power athletes, such as football players and professional weightlifters, obtain greater training benefits from strength training over circuit training. Therefore, you must consider your own fitness requirements when choosing resistance-training routines. As always, consult a doctor before starting a weight-training program.