Resistance training facilitates fat loss in a few different ways. For one, resistance training aids in the creation of more lean muscle mass. Higher amounts of lean muscle mass require an increased demand for energy expenditure, both during exercise and at rest. In other words, those with more lean muscle mass tend to burn more calories all day long.
Resistance training has also been found, along with high-intensity interval training, to increase the amount of oxygen the body requires to recover after an exercise bout. Referred to as “EPOC,” excess post-exercise oxygen consumption is a physiological phenomenon that increases the net caloric expenditure after a workout. In simple terms, you continue to burn calories after you’re done exercising. Additionally, the hormonal environment created by intense resistance training is favorable for muscle formation and fat utilization.
Nearly every resistance-training program for fat loss attempts to leverage an increase in lean muscle mass and EPOC, while creating a favorable hormonal environment to build muscle and burn fat. Various protocols manipulate different training variables, such as exercises utilized, training volume and training intensity, to convince the body to continue building muscle and burning fat.
Almost any resistance-training program will be effective in the short-term for modestly decreasing body fat (assuming proper nutrition is observed). For a program to continually be effective (the best), it’s important to understand how modifying the three essential training variables impacts fat loss.
Nearly every popular resistance-training exercise can impact the body positively in some way. However, some exercises are better than others when the goal is safe, effective and efficient fat loss. Exercises that require the coordination and movement of multiple joints, such as squats, deadlifts, Olympic lifts, pull-ups and push-ups, are the most effective for maximizing fat loss and muscle gain. These compound exercises utilize a large amount of muscle, requiring elevated oxygen use and hormonal response, and should be prioritized in an effective resistance-training program for fat loss.
Keep the exercises used in a program fairly consistent for the weeks or months in a particular training “block” (period of training with a specific goal). To prevent overuse and also allow for new ways to stimulate muscle growth and fat utilization, exercises can vary between training blocks. For example, include barbell back squats during a program for 12 weeks, and then switch to another squat or lower-body exercise variation (front squat, lunge, etc.) for another block of time.
Conclusion: The “best” resistance-training program for fat loss prioritizes compound movements.
Training volume refers to the total number of sets, reps or time under tension, and resistance (weight) utilized during a training day, month or other block of training time. This is calculated by the product of (sets X reps or time under tension X weight) used during a training day, week month, etc.
Increases in training volume are generally associated with increases in lean muscle mass (i.e., muscle hypertrophy), which is a significant contributor to the body’s ability to metabolize calories and fat. As you can see in the above equation, this can be accomplished by manipulating the number of sets, the number or repetitions or the weight utilized during exercises.
For example, help your clients progress to performing four sets of 10 repetitions instead of three sets of 10 repetitions of a particular exercise. Increase the number of repetitions of an exercise from eight to 10, or 30 seconds to 40 seconds under muscle contraction. Or, have them attempt to perform the same number of sets and repetitions as a previous training session, but increase the amount of weight used. Additional training days could be added as well to increase overall volume.
Fitness industry guidelines for set and rep ranges for muscle hypertrophy training are three to six sets for six to 12 repetitions at 50-85% of 1 RM (repetition maximum). Resistance training within these guidelines appears to be effective for increasing lean muscle mass.
While increases in training volume can be associated with the mechanisms for burning more fat, it’s important to note that these increases cannot continue indefinitely. The body’s tissues and central nervous system are finite in their capacity to handle more and more overload. Progressive increases in volume should be observed for a particular training block of weeks or months, followed by a period of decreased volume. This aids in preventing training plateaus, injury and boredom.
Conclusion: The “best” resistance training program for fat loss involves defined periods of progressively increased training volume with defined periods of decreased training volume.
Training intensity refers to the percentage of output based on an all-out effort such as a 1 repetition maximum (1RM) or repetitions to failure. Training intensity dramatically impacts the hormonal response from exercise and, in turn, increases in lean muscle mass and EPOC. And all of these contribute to the ability to burn fat.
Training intensity has been demonstrated to contribute to fat loss a few different ways. First, increasing the amount of effort (percentage of an all-out effort) creates a significant training stress, which results in a positive hormonal release and continued oxygen utilization after exercise. To maximize the effectiveness of this progression, ample recovery time (two minutes or more) between sets is recommended. Optimal recovery between sets aids in the development of strength as well. Improved strength can increase overall training intensity, in addition to training volume.
However, it appears that the most significant contributor to fat loss during resistance training has to do with increasing training intensity by decreasing rest time between sets. When rest time is decreased, significant metabolic stress is placed on the body. The result is a dramatic hormonal response that enables the utilization of fat and the creation of muscle. Shortening rest times also appears to have the most significant impact on EPOC.
Super-sets (performing two exercises in succession with opposing muscle groups) and circuits (exercises done in close succession with limited rest) are common resistance-training protocols that utilize short rest times to increase training intensity.
A word of caution: Although resistance training with shortened rest periods is often celebrated as the “best” for fat loss, it can cause significant fatigue to the central nervous system. During prolonged training blocks, this can decrease strength and overall training intensity, which negatively impacts fat loss and increases the likelihood of injury. To observe continual, long-term fat-loss results from a program, defined training blocks of weeks or months should oscillate between periods of optimal and sub-optimal recovery between sets.
From a long-term programming standpoint, training intensity and training volume often have an inverse relationship. Both have an impact on fat loss, so it’s important to create programs that allows each to be optimized during different training blocks. When training intensity is high (training at near-failure effort), the central nervous system fatigues quickly, so training volume is often limited. To increase training volume substantially, absolute training intensity must be decreased. Attempts to increase both volume and intensity concurrently for a prolonged period of time results in fatigue, exhaustion and, ultimately, injury.
Conclusion: The “best” resistance training program for fat loss utilizes blocks of both limited rest training and full recovery training to optimize training intensity. Additionally, defined training blocks should oscillate between periods of relatively low intensity with high volume and vice versa.