Bulletin No. 32, Parrillo Performance Guide To Muscle, Part 5

Parrillo Performance Products
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In the previous bulletin I introduced the “all or nothing” principle of muscle contraction, which states that a given motor unit either contracts maximally or not at all. I also explained the pattern of muscle fiber recruitment. For low intensity activities, such as fine finger movements or precise movement of the eyes, small motor units are recruited. Small motor units allow precise muscular control and are primarily composed of slow twitch fibers, which generate low forces and are fatigue resistant. As progressively more force is required for an activity, more fast twitch motor units are called into play. These have more muscle fibers connected to each nerve cell (that is, they are larger motor units) and are capable or generating high forces although they fatigue more easily. In this bulletin I would like to talk about different types of muscle contraction, and why these are important in bodybuilding. Concentric muscle actions occur when a muscle is shortening. This happens when force generated within the muscle is sufficient to overcome the resistance to shortening (1). An example is the lifting phase of a biceps dumbbell curl.

During this phase of contraction, action potentials are arriving at the neuromuscular junction, causing a release of the neurotransmitter acetylcholine at the synaptic cleft. This causes an influx of calcium into the muscle cell, as well as a release of calcium from the sarcoplasmic reticulum. (Review previous articles in this series in these concepts are fuzzy.) The rising calcium concentration sets off a series of events resulting in activation of the actin-myosin cross-bridges. ATP is consumed as the sarcomeres shorten, bringing the Z lines at the ends of the sarcomere closer together. Thus when a muscle fiber contracts, each of the individual sarcomeres contract, and ATP is consumed. Concentric muscle actions are really the only true muscular contractions, because contraction literally means “to shorten.” Isometric muscle actions refer to the situation where the force generated by the muscle is sufficient to exactly balance the resistance. An example is at the top of a biceps curl at the moment of peak contraction, or any time when you pause during the curl and the weight remains stationary. “Isometric” means “the same length,” and thus describes any time a muscle is working but is not changing in length. Eccentric muscle actions refer to situations when the muscle is generating force but that force is less than the resistance on the muscle. An example is the lowering phase of a biceps curl. Here, the muscle is still working and generating force, but the muscle is actually getting longer.

Gravity is the force pulling the dumbbell downward, and this force is transmitted to the forearm and then to the biceps tendon. If this force is greater than the internal force generated by the biceps muscle, then the muscle will lengthen instead of contracting, even though it is still working and generating force. “Isokinetic” means “the same velocity” and describes muscle actions that occur at constant velocity. An isokinetic contraction is simply a concentric muscle action that occurs at constant velocity. It is important to realize that during isometric and eccentric muscle actions we still have nerve impulses (action potentials) arriving at the muscle, triggering calcium release and activation of the actin-myosin cross-bridges, just like we do during concentric actions. The difference is that the force generated by the muscle is no longer sufficient to overcome the resistance. During isometric actions the sarcomeres remain the same length, and during eccentric actions the sarcomeres actually get longer. During eccentric actions the actin-myosin cross-bridges are still trying to pull the Z lines together to shorten the sarcomere, but they’re just not strong enough.

As you might imagine, this causes quite a bit of damage to the cross-bridges and to the whole sarcomere. The sarcomere is working to contract, but is being overcome by external forces which are forcing it to lengthen while it is trying to contract. This is the main source of microtrauma (microscopic damage) to the muscle that occurs when you work out. If you take a muscle biopsy (a small tissue sample) from a muscle after a workout and look at it in the electron microscope, you will see that the normal structure of the muscle has been disrupted. The amount of damage to the muscle is far greater following eccentric actions than for concentric or isometric actions, as you might guess. In concentric actions under heavy resistance, the microscopic structures of the muscle fiber literally get ripped apart as the muscle fiber is forced to lengthen while it is trying to contract. Following intense training sessions we see a phenomenon called “Z band steaming,” which describes the Z band structure being disrupted and myofilaments streaming out from the normal sarcomere structure. Under extreme conditions you can even see rupture (breakage) the sarcoplasmic membrane (the cell membrane of muscle cells) and leakage of cellular contents from the cell. Some of these can be measured in routine lab tests in a hospital.

Creatine phosphokinase (CPK) is an enzyme in muscle cells which forms creatine phosphate, the short-term energy reserve in muscle cells which is responsible for immediately replenishing ATP (refer back to our series on cellular energy metabolism). When muscle cells are damaged and the cell membrane starts leaking, CPK is released into the blood and can be measured in the laboratory. In hospitals CPK levels are used as an initial screen to tell if someone has had a heart attack or not, since during a heart attack some of the heart muscle cells die and release CPK. Skeletal muscle cells also release CPK when they are damaged. Using tests like muscle biopsy and CPK, scientists have determined that most muscle damage occurs during eccentric muscle actions, when external forces rip the myofibers apart. This is also the main cause of muscle soreness 24-48 hours after a workout, and is called “delayed onset muscle soreness,” or DOMS. Try a few sets of heavy forced negatives sometime to prove it to yourself. It is well known to bodybuilders that negatives cause the most muscle soreness, and now you know why. Why is all of this important to bodybuilders? Because it is at the very heart of muscle growth. You see, the microscopic tissue damage that occurs after weight training serves as the stimulus for inflammation. Inflammation is a process that occurs in damaged or infected tissues that signals the immune system to come into play.

White blood cells, mainly lymphocytes, neutrophils, and macrophages, are called in to clean up the mess of the damaged and leaking muscle cells. The white blood cells release immune mediators such as histamine, bradykinin, cytokines, and interleukins, which help bring about the repair process. Bradykinin is one of the immune mediators that is particularly famous for causing pain, and immune mediators like bradykinin and prostaglandins are the reason muscles get sore after a workout. During the inflammation process, damaged cells are repaired and the tissue is returned to its original state. The body doesn’t like this inflammation and repair process however, and overcompensates a bit during the repair process. The body makes the muscles a little bit bigger and stronger than they were before the workout, so that next time you hit the weights hopefully the muscles can take it and not get damaged. The body’s ability to overcompensate is very limited however, and estimates are that with each good workout your muscles increase in size only about 0.1%. This is why it takes years of consistent training to get really big muscles. There are two basic principles of bodybuilding training that are more important than all the others put together. The first is the principle of intensity. A workout must exceed some threshold of intensity in order to stimulate growth. The second is the principle of progressive resistance. This means that as you get stronger, you have to keep progressively increasing the resistance to overload the muscle. In other words, as the muscle gets stronger the intensity threshold required to stimulate further growth increases. This is a direct consequence of the over-compensation process I described above. During the inflammation and repair process, tissue remodeling occurs to help the muscle adapt to the stresses imposed on it. Initially, a 30 pound dumbbell curl may be intense enough to cause muscle damage and set into play the process of muscle growth. Muscle growth is really just an adaptive response that occurs so that the next time you curl a 30 pound dumbbell it doesn’t cause so much damage to the muscle. After a while, you will be able to curl the 30 pound dumbbell easily, without much strain or damage to the muscle. At that point, the muscle and it’s associated connective structures have adequately adapted to the stress imposed by a 30 pound dumbbell. You can keep working out with 30 pound dumbbells for the rest of your life and little, if any, additional growth will occur. The muscle has grown and adapted to that level of stress.

If you stick to the 30 pound dumbbells you will find that over time you will be able to do more and more reps with 30 pounds, but that will do little to increase muscle size. Any time you’re doing more than 12-15 reps with a weight you’re primarily training muscle endurance, not muscle strength. Training for muscle endurance is just fine, but does very little to increase muscle size. To increase muscle size you have to increase strength, which means lifting a heavier weight. So you go up to the 35 pound dumbbells and get maybe 6 reps before your biceps fails. This represents a new level of stress, a higher level of intensity, and the adaptation process begins again. After a few weeks or months you will be able to curl the 35 pound dumbbells for 12 reps and your biceps will be bigger and stronger than it was when you could only curl 30 pounds for 12 reps. This is the principle of progressive resistance. For maximal gains in strength, you want to train with a heavy weight at low reps, say 3-6 reps. For maximal gains in muscle size, you want to train with a weight you can handle for 6-10 reps. As the muscle adapts and gets stronger, you will need to increase the weight in small increments (about 5-10% per jump) to keep yourself in the proper rep range. The most effective training strategies over the long haul involve some work in the 3-6 rep range and some work in the 6-10 rep range. This helps train the nervous system as well as the muscle and helps ensure the high threshold pathways are recruited. For purposes of increasing muscle size and strength, by the time you can perform 12 reps with a given weight this means it’s time to increase the load. Just how does this process of muscle growth and adaptation occur? There are two basic mechanisms that come into play: hypertrophy and hyperplasia. Muscle hypertrophy means that an individual muscle cell gets bigger. This occurs as it builds more myofibrils by adding more actin and myosin (and other associated structures). In other words, an individual muscle cell builds more contractile proteins inside it, making it increase in diameter.

This of course also makes it stronger and able to generate more force when it contracts. Muscle hyperplasia describes the situation of adding more muscle cells. Hypertrophy is an increase in muscle cell size, and hyperplasia is an increase in muscle cell number. The overwhelming body of scientific evidence indicates that most muscle growth is the result of hypertrophy (2,3). If you take biopsy samples of muscle before and after a training program, you will see that after training there are still about the same number of muscle fibers (muscle cells), but that each muscle fiber is bigger in diameter. This indicates that hypertrophy is a more important adaptive response to exercise training that is hyperplasia. Several studies with bodybuilders do indicate however that muscle hyperplasia can occur. In these studies it was found that bodybuilders had more muscle fibers (cells) per cross-sectional area than untrained controls (2,3). One experiment with cats demonstrated a 9% increase in fiber number following 101 weeks of resistance leg training (2,3). To reconcile these observations with the body of data suggesting that most muscle growth occurs by fiber hypertrophy, it was suggested that in order for muscle cell hyperplasia to occur the training stimulus must be of high intensity, with heavy resistance and low repetitions (2,3). Most studies in exercise physiology use untrained subjects, with moderate to low resistance and higher repetitions. While both growth mechanisms are probably at play in bodybuilders, most experts agree that most muscle growth occurs by hypertrophy of existing muscle fibers. When muscle cells do undergo hyperplasia, what is the source of the new muscle cells and the stimulus for their growth? This question is of course of great interest to bodybuilders, since it is the door to almost unlimited muscle growth. New muscle cells are believed to derive from differentiation and proliferation of satellite cells. Satellite cells are little tiny cells not much bigger than nuclei, and are found along the periphery of muscle fibers. Satellite cells seem to be most active during the growth of the fetus, while it is rapidly forming new muscle tissue. During adult life, satellite cells can be induced to turn into new muscle cells by factors released from damaged muscle cells (4). When satellite cells were placed in culture dishes it was found that they could be induced to differentiate (turn into new muscle cells) by adding an extract from minced or ground up muscle tissue (4). An extract from undamaged muscle or from some other tissue could not do the trick. Thus it appears that muscle cells contain some substance that can leak out when the cell membrane is damaged, and this substance acts as a signal to cause the satellite cells to grow. The idea is that satellite cells represent a reserve source of precursor cells that can be called upon following muscle damage, to make new muscle cells and repair the damaged muscle. This all makes sense if you think about it. We know that most muscle cell hyperplasia comes about as a result of high resistance training with heavy weight (2). We also now that high resistance training, especially the eccentric phase of the muscle action, results in the most muscle damage (1,2,3). Finally, we also know that high resistance training is the most effective stimulus for increasing muscle size and strength (1,2,3). So it all fits together. And this is why it’s vitally important for bodybuilders to pay special attention to the lowering phase of each rep - it’s the most important part of the rep for stimulating muscle growth. You should always lower the weight slowly and resist the weight on the way down. This type of training will make you sore, but it’s the best stimulus for muscle growth.

I don’t recommend negative-only training, however. You still need the positive (lifting) part of the rep to fully work the muscle and to exhaust its ATP stores. Since the muscle requires ATP to relax as well as to contract, if you use up the ATP in the positive phase of the movement, this will result in greater microtrauma during the eccentric phase. And this, presumably, will trigger a greater adaptive response and more muscle growth. The Parrillo program is founded on the basics to help this process work at peak efficiency. I’m sorry, but there really are no tricks or secrets. It takes dedication, consistency, and hard work. What do you do? First, you have to make every workout count. Every workout must be intense enough to stimulate muscle growth, or you’re just wasting your time in the gym. You have to attack each workout. Think of the weights as enemies to be conquered - to be slaughtered. Walk into the gym with a feeling of overwhelming power. The weights simply are not strong enough to resist you. You WILL lift heavy weights today. Get in there, kill the weights, and get out. That’s your job. Second, supply your body with more than adequate amounts of every nutrient it needs to build muscle. Protein, carbohydrate, vitamins, minerals, branched chain amino acids - and most importantly, a foundation of solid nutritious food. Start with a solid bodybuilding diet and add supplements to boost cellular nutrient levels even higher. Don’t compromise on nutrition. Can you imagine going to all that work of busting your butt in the gym and then not growing because of sub-optimal nutrition?

The optimal bodybuilding diet is laid out in detail in the Parrillo Performance Nutrition Manual. Which foods to eat ,which foods to avoid, how much protein, carbs, and fat, how many calories, how many meals, and everything else you need to know. It even comes with a food scale and a food composition guide, so you can precisely structure each meal for optimal results. After the foundation is laid with the right foods, then add in supplements to boost nutrient levels even higher. Start with the basics: Hi-Protein Powder^TM, Pro-Carb^TM, , Vitamins, and Minerals. Add in Muscle Amino^TM, for extra branched chain amino acids - the primary structural amino acids in muscle protein. If you’re a hard gainer or want faster results, add in CapTri®. CapTri® supplies calories which are preferentially used for energy, sparing amino acids so they can be used to build protein instead of being burned as fuel. The special thing about CapTri® is that excess calories from CapTri® are readily burned as body heat instead of being converted to body fat. This makes CapTri® THE BEST way to add calories to your diet in a way that will minimize body fat. It’s a hard gainer’s dream come true. Third, get adequate rest to allow muscles to recover between workouts. This is a must. Remember, muscles don’t grow in the gym - they get damaged in the gym.

The growth phase occurs during the next couple of days following a workout while the muscles are recovering. You have to get adequate rest for this recovery process to occur optimally. There’s no simple answer to the questions of how often should you train each muscle, or how many days a week should you train. Trainers and muscle physiologists have been studying this for years, and still don’t know the answer. The reason is that the optimal training protocol is different for different people. Hard gainers do better with less work and more time for recovery - say, training three days a week on a one on - one off schedule. People who are naturally muscular and gain muscle easily often can train more, three on and one off, for example. Some people even do well training every day, training one muscle group each day. Some professionals train twice a day. The optimal schedule for you depends or your own body’s recovery ability as well as how many other stressors you have in your life. If you work 60 hours a week, for example, this takes a big toll on your recovery ability, and you probably won’t be able to recover from daily workouts. Professional bodybuilders don’t have any other job to worry about, so they are at an advantage in terms of recovery. You will have to experiment to find the best routine for your body. There are some basics however, that are true for everybody. You have to train hard. You have to give each workout everything you’ve got. You have to keep slowly increasing the resistance and getting stronger. The Parrillo Performance Training Manual describes all the best exercises for bodybuilders, with descriptions of proper exercise performance and sample routines.

There’s enough in there to take you from the beginning level all the way through the professional ranks. Start off with the Nutrition and Training Manuals, which are where you get the information you need to reach your bodybuilding goals. At any time, feel free to call or write with questions or for personal counseling. We support our program all the way - we don’t just sell you something and then turn you loose. What sets us apart is that Parrillo is a comprehensive package, a total program of training and nutrition, which is supported all the way. We supply information, not just supplements. We actually teach you what you need to know to become the best you can be. Who else does that? Who else sends out a free magazine to customers with scientific information about bodybuilding endocrinology, cellular energy metabolism, and muscle physiology just to educate customers so they can get the most out of the workouts? Nobody else. A lot of people sell supplements, but nobody else does what we do. We’re for real. We’re here for the few people out there who are really serious about reaching their goals. We believe that people who are dedicated and work hard in the gym deserve results. When you buy supplements from somebody else, that’s all you get. But when you buy supplements or a manual from Parrillo, that’s just the beginning of a relationship. That’s our commitment to you. To supply not only the products, but more importantly the support and information you need to get results. That’s why the serious people end up with Parrillo.

Parrillo Performance Products
(800) 344-3404

References

1. Baechle TR. Essentials of Strength Training and Conditioning. Human Kinetics, Champaign, IL, 1994.
2. Wilmore JH and Costill DL. Physiology of Sport and Exercise. Human Kinetics, Champaign, IL, 1994.
3. McArdle WD, Katch FI, and Katch VL. Exercise Physiology - Energy, Nutrition, and Human Performance. Lea & Febiger, Malvern, PA, 1991.
4. Lieber RL. Skeletal Muscle Structure and Function. Williams and Wilkins, Baltimore, MD, 1992.

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