Exercise: The Key to Releasing Fat Burning and Muscle Building Hormones
Gaining mastery of one's hormonal framework lies at the heart of attaining the lean, muscular physique that admits no flaws. Bulging biceps, sweeping shoulders, a slender midsection, and powerful legs emerge from the proper manipulation of the myriad of hormones that dictate our physical and emotional state. The body, being very resistant to change, must be attacked with the precise application of the correct stimulus to achieve the desired result. The chosen instrument is commonly exercise, a wise selection, but its usual application is so fraught with holes that it does little more than offer a disservice to the innocent trainee.
The haphazard approach to exercise has never been an effective avenue for physique enhancement. For all but the genetic elite, this undertaking is met with futility and disappointment, culminating in a newfound hatred for the pursuit of fitness and health. Caught in the web of exercise's many intricacies are its ambitious disciples, the exercising enthusiasts that inevitably fall prey to the latest training vogue. Lost in their aspirations for a body that demands admiration, however, is an appreciation for science. Advancing constantly, science offers hope that the body will resoundingly conquer the beast that is exercise. With new research comes answers, results, and a shredded set of abdominals.
The Myth of "Getting Toned"
Upon questioning the novice about his training goals, the most common answer is undoubtedly a burning devotion to become "toned." In his mind he fancies the look of solid pecs and a six-pack of abs - not quite as much muscle as Arnold Schwarzenegger, yet quite a bit more than Gandhi. However, in his quest he justifies ineffective training tactics, such as utilizing so-called "shaping and toning" exercises, citing his abhorrence for squats, deadlifts, and strenuous training because he longs to be lean and graceful, not beefy and awkward. Label him victimized, uninformed, and eventually frustrated.
Molding a lean, muscular physique involves both the production of added muscular mass as well as a corresponding decrease in adipose tissue (fat). This much is obvious. Within the common approach, however, arise the flaws. Whether the goal is muscle gain or fat loss or both, the prescription for releasing hormones that generate the desired effect is the same. The type of program utilized -- specifically, the exercises employed, the intensity at which they are performed, and the duration of activity -- is what ultimately determines the alterations in body composition. When the proper exercise program is followed, the ensuing hormonal changes result in such desirable effects as increased lean body mass and strength, and decreased fat. With these physical effects come a heightening of general health, fitness, and self-worth.
The primary mode to achieving the coveted "ripped" appearance should be to increase lean body mass. As muscle mass increases, so too does the metabolic rate and the potential for fat loss. For every one pound of muscle that is gained, upwards of 100 additional calories daily are burned at rest. By far the most efficient formula for increasing lean body mass is weight training. However, although utilizing the precise methodology will result in cherished new muscle, a faulty approach will only pave the path of disgust.
The second procedure for attaining a prized physique is to directly stimulate lipolysis, or fat burning. The most common method employed is to use a low intensity exercise regimen for a long duration. While this is an appropriate protocol for tapping into fat stores directly, it is not effective for many reasons. First of all, it is an insufficient method to increase the metabolic rate. Second, its apparent efficiency in burning fat is shattered by the astonishing fact that one pound of adipose tissue can supply the body continuously for over ten hours. Compounding that revelation is the notion that, although fat stores are utilized, there are no guarantees that the fatty acid energy source is derived from adipose tissue. Other potential sources are plasma free fatty acids and intramuscular triglycerides, which do not directly stimulate fat loss (10, 18). The trainee is then left with two choices: exercise continuously for 72 hours at a time, or stimulate the appropriate fat burning hormones. The choice is elementary.
Igniting the Muscle Building and Fat Burning Stimulus
As stated, it is the type of program utilized that ultimately dictates the corresponding hormonal response. Both muscle and fatty tissue adapt to the fluctuating concentration of circulating hormones. In the case of a muscle fiber, it must be broken down systematically through resistance training. The fiber, in turn, responds with an increase in the synthesis of new contractile proteins that result in the fiber becoming larger and stronger. This growth response is the result of the presence of potent anabolic (muscle-building) hormones whose function is to promote protein synthesis. As more fibers are involved, a greater hormonal response is necessary, and thus greater changes in whole muscle are possible (1).
Related to this concept is the motor unit, defined as a motor neuron and all the muscle fibers that it innervates. To involve the greatest number of muscle fibers, the largest motor units must be stimulated. Upon excitation of these motor units, numerous signals are sent from the brain to various endocrine (hormone-producing) glands (1). As the number of activated muscle fibers increases, a multitude of responses occurs which prime the muscle for the acceptance of the anabolic hormones that result in muscle growth and strength (1). Recruiting these large motor units demands utilization of heavy resistance training with exercises involving multiple muscle groups. This means applying exercises such as the squat, deadlift, bench press, and shoulder press into the routines of those seeking improved muscular development.
Gaining appreciable muscle mass is a constant internal struggle between protein synthesis and protein degradation. Influencing the conflict are numerous external factors, such as recuperation, intensity of training, diet, and genetics. These elements also have an astounding effect on the hormonal environment. The specific hormones involved can be grouped into anabolic and catabolic (growth inhibiting) categories. The objective of exercise is to apply the precise stimulus to induce an anabolic response. However, if the stress is too great, the catabolic hormones will supersede their anabolic counterparts and overtraining will invariably result. To avoid this, strict attention must be paid to appropriate recuperation and diet. Furthermore, intermittent layoffs and periods of decreased training intensity are necessary to augment future muscle hypertrophy, since the hormonal response is increased after these intervals.
Although fat burning is a welcome by-product of larger muscles, there also exist hormones (some that are also anabolic) that dramatically slash body fat percentages and midsections alike. Their release is correspondingly spawned through strenuous activity and specific training protocols. For instance, intense running or a decreased rest interval between sets of weight training has proven to be very effective at maximally stimulating fat-burning hormones. Remarkably, an advantage it has over muscle building is the fact that as training experience increases, the propensity for lipolysis is additionally enhanced (3, 4, 13, 16).
The Hormonal Contestants
Well practiced in the art of muscular growth is testosterone. A remarkably potent hormone, it directly increases protein synthesis and exhibits an intimate relationship with the nervous system. It is testosterone that is activated by exercises involving large motor unit stimulation that result in increased structural changes within muscle (11). In short, testosterone spurs extraordinary muscular growth and strength. In addition to its vaunted effects on protein synthesis, it may also indirectly stimulate the release of another anabolic substance, growth hormone.
Growth Hormone (GH), as its name implies, is another powerful stimulant of anabolism that also sprinkles in a few favorable twists. Not only does it promote muscular growth, but it is also involved in increasing lipolysis, lowering blood pressure, and improving the immune system. Though not fully understood, many of its actions also involve the excitation of a third set of anabolic hormones, the insulin-like growth factors (IGFs). Stimulating the release of IGFs increases the availability of amino acids for protein synthesis and results in greater tissue repair and growth (1). As was the case with testosterone, it appears that the recruitment of large motor units is necessary for GH to exert its anabolic and lipolytic effects (17).
The catecholamines are an interesting group of hormones. Among their vast array of effects are an increased use of fat for energy, increased contraction rate and force production of muscle, and an augmentation of other hormones such as testosterone and the IGFs. The catecholamines, mainly epinephrine and norepinephrine, may also inhibit the release of insulin, a hormone that pushes free fatty acids back into fat cells (13). Through this inhibition and their influence on the liver to cause adipose tissue lipolysis, the catecholamines make stripping a much less embarrassing proposition.
Unfortunately, a continual rise in anabolic hormones triggers counteractive mechanisms to maintain the body's present state. This drawback is effectively accomplished by the representative catabolic hormone, cortisol. Though it may increase the mobilization of free fatty acids, this effect is largely overshadowed by its protein breakdown activity. With cortisol, which is released under physical and emotional stress, amino acids are burned for energy instead of utilized for growth. This increases the likelihood of muscular atrophy in the face of strenuous exercise, which for some is a free ticket to insanity. In the long term, excessively high cortisol levels can even diminish physical health.
Unleashing the Hormonal Arsenal
It is never too late to take advantage of the benefits of the preceding hormones. With effort comes progress, and with progress comes motivation. Initiating an exercise program and adhering to it are very difficult without proper planning and goals, but it soon becomes instinctive as obstacles are surmounted and character is elevated. With adequate knowledge of how hormonal monopoly is achieved, the keys to the internal framework are revealed and mastery is gained.
Since muscle growth is a primary objective, taking command of testosterone and GH is mandatory. In the gym, this translates to using large muscle group exercises, heavy resistance, short rest intervals, and moderate to high volume. It is very rare to see this combination of factors employed consistently by most weight trainers. Why? Because it's often excruciating and requires a mind bent on pillage! Leg extensions and concentration curls have their place, but nothing will stimulate shocking whole-body reconstruction like squats and deadlifts. Remember, with large motor unit stimulation and exhaustion comes an unparalleled release in anabolic hormones.
The next factor to consider is the amount of weight lifted, including the number of repetitions performed. For optimal testosterone release, a resistance that is 85-95% of a one-rep maximum should be utilized (1). For instance, 90% of a 200 lbs. maximum bench press is 180 lbs., and this weight would allow approximately five repetitions, an ideal range. To further augment testosterone release, a one to three minute rest interval between sets is necessary (1). The release of growth hormone closely parallels that of testosterone; however, higher repetitions are optimal, along with short rest periods. The most prolific regimen for GH release appears to be a ten rep maximum approach with one minute rest intervals, which can increase production 20-40 times above baseline levels (1, 13). One research study displayed an even greater increase from a set of 25-rep squats (9). These fluctuations in optimal hormone release conveniently point to the necessity of training variability.
Variety in training may be one of the most important but overlooked concepts in all of exercise. Given the body's tremendous ability to adapt to physical stress, continual variation between individual workouts is imperative. For instance, the differences in the optimal release of testosterone and GH provide an excellent basis for modifications between training sessions. Applying a 5/1 (five rep max, one minute rest) approach for one workout and a 10/1 approach on another prevents plateauing and boredom; it also more efficiently allows for progressive increases in resistance to be maintained between workouts. Also, a 5/1 approach may be optimal for maximum testosterone release, but it may require a decrease in the amount of resistance used on subsequent sets. In this case, a 5/3 protocol adds the spice of variety. Other profitable tips for avoiding the humdrum of training include periodically changing exercises, the speed at which repetitions are performed, and hand/foot placement.
A final factor influencing muscle gain, which can also be manipulated for variety, is the volume of training. This most readily refers to the amount of sets to be performed in a given workout, as well as the amount of recuperation permitted between training sessions. These conditions appear to be largely influenced by individual variation. As a general rule, however, weight training sessions should be limited to approximately 45 minutes. This is due to the fact that the anabolic/catabolic hormonal ratio begins to tip in favor of cortisol at this time. With this in mind, the amount of sets to be performed should be dictated by the chosen rest interval. For example, a one minute rest interval will allow the performance of numerous sets, while a three minute interval will permit using greater resistance.
Generally, however, larger muscle groups (i.e., legs, back, chest) require a greater number of sets than smaller groups (i.e., biceps, triceps). Given this notion, larger muscle groups should comprise 60-75% of the total work sets. For example, if a high intensity workout (5 rep max, 3 minute rest, 45 minutes total) consists of 14 total sets (not including warmup), the large muscle groups would account for approximately 8-10 sets, while the smaller groups would take 4-6 sets.
Determining the number of days between workouts of the same body part is subject to tremendous variation. Some thrive on training five to six times weekly, while others can withstand only two or three. The factors influencing this variable of training volume are innumerable, but the most important ones appear to be training experience, intensity of training, diet, and the exercises employed. Beginners will experience a great degree of delayed onset muscle soreness when initiating a weight-training program and hence will require more rest. Additionally, more recovery is required after sessions of high intensity training. High intensity, in this case, refers to training to muscular failure with near maximal poundages. When choosing exercises, also bear in mind that larger muscles require more recuperation. Thus when training with movements that recruit a great number of muscle fibers (i.e. squats and deadlifts), more rest is necessary.
Shedding the Fat
A favorable side-effect of GH release through weight training is an increase in lipolytic activity. GH appears to stimulate the production of adipolytic lipase, an enzyme which mobilizes fats, and this serves to trigger a shift towards using fatty acids as an energy source (13). Though a weight training regimen that utilizes high repetition maximums and minimal rest is rather taxing in its own right, large GH peaks have also been discovered during high intensity running. Specifically, the trainee should utilize a running intensity that is 75-90% of maximal heart rate to adequately stimulate GH output (max heart rate can be obtained by calculating 220-age). Obviously, this will not allow for long durations, so periodic walking should be performed between sets of high intensity running. A further advantage to this form of training is that it burns calories at a higher rate than any other activity and improves cardiovascular fitness dramatically.
In addition to GH, the catecholamines have extraordinary effects on fat loss. They are also very responsive to high intensity training with minimal breaks, which can increase levels to over 20 times those at rest (12). Two important factors concerning the effects of the catecholamines, however, are training experience and the presence of glucose in the bloodstream. Incredibly, as training experience increases, the body becomes more efficient at burning fat, such that there may be a 50-80% increase in the amount of free fatty acids mobilized when in the trained state (3, 16). This may be due lactic acid, a by-product of energy expenditure that is responsible for the burning sensation during training. As lactic acid concentration increases, the use of free fatty acids for energy decreases (8). This may be a drawback to training at high intensities and short rest intervals; however, as the body becomes more adept at handling this type of training, fat burning capabilities increase remarkably. Lactic acid is, however, associated with increases in circulating growth hormone (1). As a result, further augmentation of the fat burning response is seen at rest. With chronic training, there is a significant increase in the amount of fatty acids expended at rest, and a shift toward using them for energy during recovery (13).
A second factor that initiates a greater response from the catecholamines is a decreased blood glucose level (4). Specifically, epinephrine release is heightened in situations where glucose levels are low, as is the case upon awakening. This would preferably tap into adipose tissue for energy as the body attempts to maintain the depleted glucose stores. By this rationale, morning workouts, as agonizing as they may sound, are ideal.
Similarly related to the topic of glucose is the hormone insulin. As blood glucose levels rise, so does insulin, and the amount of free fatty acid mobilization decreases. This provides more support for morning workouts; it also advises against the ingestion of foods containing high amounts of sugar prior to training, which spike levels of blood glucose. Fortunately for those seeking physique enhancement, however, insulin release is inhibited by high intensity training (15).
Adaptation: An Unnecessary Evil
Besides a lack of motivation, a lack of progress is probably the number one reason trainees prematurely quit their exercise programs. Then again, a lack of motivation is often the result of dwindling progress. To avoid staleness in training, considerable attention has been paid to variation, but necessary periods of decreased training intensity have not been addressed. For example, the use of progressive resistance (a gradual increase in loads over time) is necessary for improvement, but this may also serve to facilitate the release of cortisol. To avoid this explicit danger, training intensities should not be increased linearly; rather, periods of high intensity training should be followed by periods of low to medium intensity exercise for maximal progress. The detrimental effects of cortisol also seem to be most pronounced during periods of concurrent endurance and strength training (2, 14).
Another reason for scant progress is the continual loading of the same muscle fibers, as is the case when employing the same exercises for a succession of workouts. As muscle fibers approach genetically predetermined levels of hypertrophy, the amount of protein synthesis occurring in those fibers decreases (1). Further growth instead becomes possible through the lack of protein degradation, effectively endorsing the use of variation in exercise selection and procedure (1). Varying the manner in which exercises are performed (i.e. hand/foot placement, repetition tempo), as well as periodically using different exercises altogether, will stimulate otherwise tranquil muscle fibers into new growth.
Putting It All Together
Note: The following are considered the best exercises for stimulating the greatest amount of muscle fibers. These should provide the basis of any weight training program; however, exercises must be periodically alternated to maintain progress.
Chest: Bench Press, Incline Bench Press, Decline Bench Press (all three may be performed with a barbell or dumbbells); Weighted Parallel Bar Dips
Shoulders: Shoulder Press (barbell or dumbbells), Lateral Raises
Back: Deadlifts, Chin-ups, Bent-over Rows, One-arm Dumbbell Rows, Seated Pulley Rows
Arms: Standing Barbell Curls, Incline Dumbbell Curls, Closed-grip Bench presses, Lying Tricep Extensions
Abdominals: variations of weighted crunches
Legs: Back Squats, Front Squats, Leg Press, Hack Squats, Deadlifts, Stiff-legged Deadlifts, Leg Curl
Calves: Standing Calf Raises, Seated Calf Raises
The Short Term Plan
Note: The following are only examples of short term training schedules. There is no perfect program for everybody. The trainee should select the most accomodating one, or use a similar variation depending on individual discrepancies.
|Day||Workout A||Workout B||Workout C|
|1||Chest, Front Shoulders||Back, Rear Shoulders, Biceps||Chest, Back|
|2||Legs, Calves, Abs||Rest||Legs, Abs|
|3||Rest||Chest, Front Shoulders, Triceps||Shoulders, Calves|
|5||Back, Rear Shoulders||Legs, Calves, Abs||Deadlifts, Arms|
|6||Arms, Calves, Abs||Rest||Rest|
|7||Rest||Rest||(Begin with Day 1)|
With the exception of Workout C, deadlifts should be performed with back training.
In general, smaller muscle groups (i.e. biceps, triceps, and calves) can be trained more frequently. For instance, Workout A may include arms on Day 1 as well as Day 6, while Workout B may include additional arm training on Day 5 or 6.
Although larger muscle groups require more recovery between workouts, they generally demand a higher volume of training (i.e. more total sets).
Strict adherence must be paid to proper exercise form. Additionally, exercises should be executed through the entire range of motion at a relatively slow pace to fully target the working muscle. However, slight modifications in repetition tempo are an excellent variation.
The eccentric (lowering) phase of the repetition should be performed especially slow. This is due to the fact that most of the microscopic damage incurred by muscle is due to this phase of contraction. Provided sufficient recuperation is allowed, this leads to increased muscular development.
Always perform a sufficient warmup before weight training. This includes proper stretching and stationary bicycling at a moderate pace.
The Long Term Plan
Note: RM = repetition maximum; RI = rest interval; E/B = no. of exercises/bodypart; DUR = phase duration. * The total number of sets performed per workout is determined by the rest interval; workouts should not exceed 45-60 minutes.
|Phase 1: High Intensity/ Low Volume||5||3 min.||2-3||2-3 weeks|
|Phase 2: Moderate Intensity/ High Volume||10-12||1 min.||2-4||2-3 weeks|
|Phase 3: Low Intensity/ Low Volume||N/A||2-5 min.||2-3||1-2 weeks|
|Phase 4: High Intensity/ Moderate Volume||5-7||1-2 min.||2-3||2-3 weeks|
|Phase 5: Moderate Intensity/ Moderate Volume||8-10||1-2 min.||2-4||2-3 weeks|
|Phase 6: Low Intensity/ Low Volume||N/A||2-5 min.||2-3||1-2 weeks|
Maintain a training log to monitor progress. This is a very efficient method to determine if continual strength gains are achieved and if rest days are of sufficient duration.
With the exception of low intensity phases, always strive to reach muscular failure within each set. This means that no further repetitions are possible without the aid of a spotter.
Obey the principle of progressive resistance by continually applying greater loads within each phase. For example, loads can be increased by using a greater amount of weight, adding forced repetitions with the aid of a spotter, or by performing two exercises consecutively before resting.
Return to Phase 1 after the cycle is complete and utilize greater loads than performed previously. However, the phases set forth serve only as an example of a long-term plan. Phases may also include periods of greater or lesser repetitions, rest intervals, and exercises to increase variation.
Periods of low intensity/ low volume training should be considerably less strenuous to prevent overtraining and catabolism. They also serve to "prime" the body for greater increases in strength and hypertrophy. Avoid large multi-joint exercises such as squats and deadlifts during this phase.
Cardiovascular training should be performed after weight training sessions or separately upon awakening. At a maximum, cardiovascular training should consist of 20-30 minutes of exercise, two to three times weekly. For those seeking muscular gains exclusively, this type of training should be avoided.
Consume a high protein diet (.8 to 1.5g protein/lb. of lean body mass), especially during training periods of high intensity or volume. Adequate protein is also crucial immediately following a workout. Without it, muscular growth is impossible.
Drink 8-12 glasses of water per day for suffiecient muscle hydration.
Beginning weight trainers should follow a non-vigorous regimen for approximately six weeks before initiating an intensive weight training program. Repetitions should be performed in the 8-12 range to allow for tendon strengthening and familiarity with the exercises. Progressive resistance should be followed, but training to failure is not recommended.
Prerequisite: A Pulse
With knowledge of proper exercise firmly in hand, a renewed vigor for superb health and self-confidence is readily attained. The excuses may be limitless, but so are the results of a systematic training program. Age, previous experience, time, and fear are irrelevant circumstances. The immediate present is the opportune time to benefit from the many arduous years of research in the field of physique augmentation. By seizing command of the omnipotent hormonal arsenal that dwells at our core, a newfound flesh awaits the surface.
About the Author
Dr. Stout has a diversified background in exercise science. His primary fields of expertise are sports supplements, neuromuscular fatigue, and body composition analysis. He has over 70 published manuscripts, abstracts, and national presentations in nationally and internationally recognized journals. Dr. Stout currently serves as assistant professor at Creighton University and is the director of the Human Performance Research Laboratory. His current teaching responsibilities include courses in exercise physiology, statistics, research design, and biomechanics.
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