Hypertrophy - The Science of getting BIG (part 1)

In this part 1 of hypertrophy, I will focus on the physiology and anatomy of how and why our muscles grow through training. In parts 2 and 3, I will focus on the training needed for maximum hypertrophy and the nutritional demands and supplementation.

There are two ways that a muscle can grow and increase in its cross-sectional area (CSA). The increase in whole muscle CSA is primarily attributed to an increase in individual muscle fiber CSA. The other way of increasing muscle CSA is fiber hyperplasia, or the increase in number of muscle fibers within a certain muscle. This is still an ongoing debate within the topic of muscle hypertrophy (the fiber hyperplasia that is).

Individual fiber hypertrophy is a result an increase of protein synthesis (creation or building of more). Protein synthesis is always changing but the rate at which it changes is a result of the net gains of protein synthesis and protein degradation. Resistance training results in a net protein synthesis (Synthesis > Degradation).

During the exercise, degradation is higher than synthesis, but after exercise, during recovery, the synthesis increases and a net protein gain is the result. So adequate recovery is vital in gaining muscle mass (see article on exerQ – Strength training and recovery times). It involves an increase of contractile proteins actin and myosin (within myofibrils) and an increase in the myofibrils themselves. Other proteins such as structural proteins titin and nebulin for example also increase proportionally. A 2002 study by Roth et al. showed than resistance training alters up to 70 genes that almost all result in up regulation of muscle growth and down regulation of growth inhibitory factors.

Fiber hyperplasia has been shown to occur in animals but there is limited research and evidence that it occurs in humans. It has been shown to occur in animals under very high intensity resistance training. It has been shown that well trained athletes possess more fibers than untrained but it is uncertain whether or not it is to do with natural genetics or induced changes from training. Hyperplasia therefore cannot be thought of as a major contributor to muscle hypertrophy as there is little evidence of it in humans and if there is, it only contributes to > 10% of total hypertrophy.

So overall, individual muscle fiber hypertrophy and an increase in fiber CSA is the main reason for muscle mass increases following correct hypertrophy training periods.

JJ

check out these books
Essentials of strength training and conditioning 3rd edition - Baechle and Earle
Physiology of sport and exercise 4th edition - Wilmore, Costill, Kenney

Astronauts and Exercise in Space: New Developments

Astronauts in space can spend hours exercising everyday. This aims to counteract the detraining effect of zero gravity conditions, which cause numerous physiological changes in the body. In muscle tissue, mass and strength decrease over time. The strength loss is especially evident in the muscles used to maintain posture, as they become largely irrelevant whilst floating around a spacecraft. Another significant effect of weightlessness is a decline is the density of bone, about 2% per month on average in space. This is less reversible compared to muscular changes and can have a particularly debilitating impact on return to earth.

Cardiovascular changes include increased blood return to the heart, due to less gravity-induced pooling of blood in the legs, while the “puffy faces” of astronauts develop due to this redistribution of blood in the body. Decrease in overall blood volume also develops and can cause low blood pressure and fainting when back in normal gravity environments. Many of the changes contribute to an overall drop in maximal aerobic capacity/fitness (VO2 Max). These negative adaptations to out-of-orbit travel have generated more and more research in designing relevant exercise programs and equipment, which seeks to safeguard the future health of astronauts.

Many different types of exercise and training have been used, some proving more effective than others. Heavy “push-pull” equipment attached to the spaceship, elastic bands/cords/belts and resistive equipment have been developed, while “strap-down” treadmills and bicycles are the norm. One device, currently in use, is the advanced Resistive Exercise Device (aRED). This works with vacuum cylinders, similar to bicycle pumps in reverse, which can apply loads up to 250 kg, according to NASA. In the example of a squat, the vacuum engages as the astronaut stands up, and when squatting back down, the vacuum draws the bar back to the origin position. The main concern, even with creating beneficial weight-bearing or elastic equipment, is still a lack of a total unilateral force acting on the body such as gravity. This leaves the decreases in bone density largely unaffected.

Latest research mainly revolves around creating artificial gravity-like forces. One design, dubbed “The Space Cycle” by researchers at the National Space Biomedical Research Institute (NSBRI), aims to accomplish this while aiming to be small enough and simple enough to operate and/or repair in a spacecraft. Picture a two-person, hanging merry-go-round. A rotating wheel sits on top of a central column. On one side of the wheel a reclining bicycle is suspended. Opposite is a cage-like platform, where a second person will stand. As the one astronaut pedals the bicycle, the whole apparatus starts to spin, causing both the bicycle and the platform to rotate around the column. As the rotational speed increases, both astronauts begin to experience effects of this centrifugal force as a form of artificial gravity.

Astronauts on long-term missions presently need approximately two hours of standard exercise a day to resist the effects of micro-gravity. The Space Cycle is seen as a way of reducing this exercise time, therefore increasing the productivity of those onboard. The weight of the mechanism, which is currently constructed out of steel, poses a problem. This may be reduced in the future using carbon composite materials, which may also slightly reduce its diameter, making it possible for use on the International Space Station.

Jed

Gene Doping: From The Inside Out

Defined by the World Anti-Doping Agency as “the non-therapeutic use of cells, genes, genetic elements, or of the modulation (adjusting) of gene expression, having the capacity to improve athletic performance", this relatively new form of performance enhancement is possibly going to turn doping on it’s head, while pushing ethics and morality in sport and the sport industry to the fore.

First of all, what is a Gene?
Inside human cells, genes provide a sort of “blueprint” or instruction for protein production. Genes are made up of chains or arrangements of DNA. This determines how the cell will function and also its physical attributes.

Gene doping developed out of the concept of gene therapy; treatment developed to cure or ease genetic diseases and disorders such as muscular dystrophy or sickle-cell anaemia. Damaged or flawed genes are replaced with modified, functional ones. These same techniques that can help ordinary people stay healthier could be used to create “superathletes”; weightlifters who “naturally” have larger thigh muscles, cyclists who have more aerobic/type 1 muscle fibers or higher aerobic enzymes produced in those muscles.

Changes in the expression of genes is not a new concept in the science of the human body. Many ordinary medicines can have this effect, as well as daily activities. Training and exercise at least partly modify the expression of one’s genes. But it’s this possibly permanent baseline transformation of the building blocks of the athlete’s body using technology that could be the next big illegal thing. (And possibly is already...). Universities of Washington and Florida were able to give trichromatic vision to squirrel monkeys (naturally dichromatic, using only two primary colours) using gene therapy, possibly leading to a treatment for colour blindness in humans in the future. Higher endurance and increase in musculature in “marathon mice” arose when a group of scientists studied three proteins controlled by a gene that influence how the body manages fats and sugars. This type of research eventually turned towards athletic performance.

How does gene doping work?
Usually a performance-enhancing gene is injected into an athlete carried in a harmless/damaged virus or bacteria (a vector; vehicle to transfer foreign genetic material into another cell). These synthetic genes now in the cells result in altered production of proteins/chemicals and cell function, continuing long-term in most cases.

One of the first gene therapy products associated with genetic doping appeared on the eve of the Turin 2006 Olympic Winter Games, where Repoxygen emerged as a possible substance in use at the Games. This medication was initially considered as a way to fight anaemia.

Detection can prove very difficult. The synthetic genes used most likely appear identical to the natural genes. Identifying the vector or particles of it is possible, but only through muscle biopsies (procedure in which a piece of muscle tissue is removed and examined microscopically). This is not ideal for athlete as some damage, swelling and weakness for a short time results. Genetic “bar codes” or markers can be produced by manufacturers/scientists for their therapeutic products, but this would require input from all relevant parties and administrators. Patterns of protein production and protein levels can also sometimes be analysed. The World Anti-Doping Authority is currently working on a test to check the expression of all 25,000 of the human body's genes, which will look for abnormal patterns.

There are many dangers and possible side effects of gene doping. Often a single gene will have more than one effect in the body and over time illicit other unwanted responses from the body. As with most substances, people’s bodies respond differently and their immune systems especially so. What looked like a successful bid to cure a severe immuno-deficiency disorder, the so-called bubble-baby syndrome, was stopped when some of the children in a French study developed leukaemia, which proved unexplainable. Increased risk of cancer is often a result of the change in DNA within cells. Some hereditary genes might become altered which will then affect children born to athletes. (Interesting thought: If those children grow up to be athletes, would they then also be identified and banned from competition...?)

The ethical issues raised are ever increasing. Cheating is taken to a whole new level. Are we getting closer and closer to playing God? With regards to the uncertainty of long-term effects, who’s to blame when things go wrong? Not only the athlete, but the sports community and society as a whole, will be harmed. Overall, the uniqueness and variety of sport would be removed.

BELGIAN BLUE BULL demonstrates the effect of blocking the antigrowth factor myostatin. A natural genetic mutation in this breed produces a truncated, ineffective form of myostatin, which allows muscle growth to go unchecked. The absence of myostatin also interferes with fat deposition, making these “double-muscled” cattle exceptionally lean.

Here's a really interesting case of when things go wrong:
http://en.wikipedia.org/wiki/Jesse_Gelsinger

Jed

‘’Catch Your Breath” Why you Breathe So Heavily During Exercise.

Have you ever experienced breathlessness while exercising and training? Why do I breathe so heavily during exercise? What can be done to improve your breathing during exercise?

I want to explain some physiological terms and reasons that will help you understand why you get breathless during exercise. Firstly during exercise and ordinary living air that enters your lungs is termed inspiration and air that leaves your lungs is termed expiration. In order for both these processes to occur there has to be a positive pressure gradient, which happens when air moves from a high pressure to a lower pressure. So when inspiration occurs, the partial pressure of oxygen in the atmosphere is greater than the partial pressure of oxygen within the lungs. Therefore the oxygen moves into the lungs, and from the lungs it moves into the bloodstream because the partial pressure of oxygen within the lungs is greater than the partial pressure within the blood. The oxygen within the bloodstream then enters the muscles and tissues due to a positive pressure gradient. Obviously when we breathe out we don’t expire oxygen but instead we expire carbon dioxide. Carbon dioxide moves outside the body cells and into the capillaries and then from there it moves into the lungs and is expired through the mouth.

Another very important aspect is hemoglobin protein that is found within the blood cells. About 98% of oxygen is transported in the blood bound to hemoglobin. The affinity of oxygen to the hemoglobin depends on the partial pressure of oxygen within the blood. At very high partial pressure of oxygen like those found in the lungs results in the hemoglobin being saturated with the oxygen molecules. This is due to the fact that there is already a great amount of oxygen within the lungs. So hemoglobin does not need to unload much oxygen there. On the opposite spectrum low partial pressures of oxygen like those found at tissue level results in a great unloading of oxygen from hemoglobin. This is because at the tissue level the cells need great amounts of oxygen to function. Obviously during exercise this will change and greater amounts of oxygen will need to be delivered to the functioning tissues. During exercise the muscle temperature increases and blood ph levels drop. Both of these factors affect the affinity of oxygen to hemoglobin. These factors both result in more oxygen being unloaded at tissue and muscle level due to the fact that the partial pressure drops.

Have you ever wondered why you breathe so heavily after exercise or even walking fast up a flight of steps? This is termed EPOC (excess postexercise oxygen consumption) and can explain the reason for heavy breathing after exercise. When you start aerobic exercise your oxygen consumption takes several minutes to reach steady state and so the aerobic energy system doesn’t function immediately. So in order to generate energy for the working muscles the body has to rely on the anaerobic pathways to produce ATP. So therefore an oxygen deficit takes place during the first stage of exercise. At the end of exercise your breathing remains elevated for some time. This is because during the initial stage of exercise some oxygen was borrowed from hemoglobin and now at the end of the exercise it has to be replenished. The respiration also remains elevated during this time of recovery to get rid of the excess carbon dioxide that is formed as a by product during the anaerobic pathways. Also the muscle temperature is increased resulting in the respiration and metabolism remaining high.

If we put all of these physiological factors together we will be able to determine why we breathe so heavily during exercise. When you start exercising your muscle temperature increases and your blood ph level drops. This results in a build up of carbon dioxide within the blood stream and muscles causing the oxygen hemoglobin curve to shift to the left resulting in oxygen being delivered to the working cells at lower partial pressures. Due to this fact there will be less oxygen returning through the system to be delivered to the active areas, and there will be greater concentrations of carbon dioxide in the system. In order to overcome this imbalance the respiratory muscles will contract at a quicker rate so that they can speed up respiratory inspiration and expiration. During the inspiration phase the lungs will try to bring in more oxygen from the atmosphere, while during the expiration phase the lungs will be getting rid of the excess carbon dioxide. So basically the heavy breathing during exercise is a result of your muscles not being able to get enough oxygen to them, and also not being able to buffer the build up of carbon dioxide. Another reason for this could be that your body is using anaerobic pathways in order to produce energy during exercise. The heavy breathing will continue during exercise and slightly afterwards due to EPOC as explained previously.

What I suggest is that before you begin exercising to go for a light jog to almost get the muscles and the aerobic system ready for what is to follow. This will ensure that the muscles know what to expect and don’t have to take drastic measures when the intensity during the exercise is increased.

Trevor Court

GI - The Glycemic Index

Everyone loves to tell you all about low GI foods, because it slowly releases energy, "it'll last longer". Which is in fact true, it does release it slowly, but what exactly does it mean, and is it always good to eat low GI foods..? Do you know which foods are low GI..? While reading the article, try thinking about foods that you know as low GI, and I will include a list at the end.

The glycemic index is used to classify foods in terms of how long they raise the blood glucose levels. The reference point on the GI scale is white bread, which has a reading of 100 on the glycemic index. Foods that have a high GI are digested quickly, they raise blood glucose rapidly and also stimulate high insulin levels (insulin aids in transporting glucose from the blood to the muscle). The exact opposite is true for lower GI foods.

Now contrary to popular belief, sugars do not always rank as higher on the scale when compared to starches. Potatoes and table rice, rank higher than normal table sugar (sucrose) also, many things can affect the GI of a particular food (cooked/uncooked, processing, is it part of a meal or a snack on its own etc…?). So although the GI of a food is important, it is not a perfect way of analyzing your diet.

Studies have been shown that low GI foods increase exercise performance (Demarco et al.) but other studies have shown no difference between eating low/high GI foods before exercise/competition (Wee et al) (Thomas et al). So if your interest is when to eat certain foods before/after/during events, try experimenting a bit as more research needs to be done on the glycemic index with regards to exercise performance.

Glycemic index of certain foods:

White Bread 99
Sponge Cake 66
Corn Flakes 116
Oats 78
White Rice 91
Brown Rice 79
Linguine (pasta) 70
Milk (full cream) 38
Honey 78
Sucrose (sugar) 97
Apple 57
Banana 74
Orange 60
Potato (baked) 121
Peanuts 21
Yoghurt (sweetener) 20

(Baechle TR, Earle RW, essentials of strength training and conditioning, 2008)

JJ

Core Gymnastics: The Rings

We have all watched gymnastics, particularly the rings at some time on our lives and wondered, how on earth do they do it, how are they so strong and we stare in awe at the unbelievable strength and bodies these guys possess. It has to be noted that these specialized gymnasts are strong all over and strength train all the muscles of their body. Now what makes them so strong, in particular, lets look at the anatomy of it...

Firstly a gymnast has to have an extremely strong base and core to stabilize the body and keep swaying and movement to a minimum. By the core, I am referring to the following muscles, some which you may not know as "core" muscles as such. Muscles of the abdomen: Rectus abdominis, Transversus abdominis, internal/external obliques. Back: Erector Spinae group, Quadratus lumborum. Hip: Hip flexors (iliopsoas), Gluteal group (maximus, medius and minimus). All these muscles provide stabilization of the joints and stabilization of the trunk. Some muscles which are generally noted as prime movers, also act is stabilizers such as the gluteal group and hip flexors. Core training can be done through various methods generally involving controlled movement on unbalanced surfaces. For example a side bridge with shoulder and leg abduction, the core works hard to stabilize the bodies joints for a controlled slow movement to occur in the shoulder and hip joint as the body remains still.

Secondly the muscles of the shoulder girdle. Obviously in the rings, all the muscles of the body work hard, but the muscles that make up the shoulder complex and the muscles that act on the shoulder joint all play a massive role. Firstly the Pectoral region. Pectoralis major and pectoralis minor. The pec major mainly adducts (as in dumbbell fly's) and rotates the arm medially (inwards). Secondly the deltoids, abducts, extends, flexes arm (moves arm forward, backward and sideways away from the body). Thirdly the Triceps Brachii (extends the forearm at the elbow). Also the Latissimus dorsi (extends, adducts, rotates arm medially). These muscles jump out at us as the strong, prime movers in the main action of gymnastic rings. The first two on the shoulder joint and the third on the elbow, and the latter on the shoulder and scapula. But not to be overlooked are the stabilizing muscles in the performing of ring exercises. To start there is the serrarus anterior. This muscle connects the ribs to the scapular, it is a broad thin muscle that can move the scapula down and anteriorly but mainly assists in stabilizing the scapula through a range of movements. The rotator cuff group (supraspinatus, infraspinatus, teres minor and subscapularis). This group also moves the humerus in the shoulder joint through external and internal rotation as well as abduction, but also mainly stabilizes and assists the larger muscle groups through all movements. The Trapezius muscle (all fibres) and the two Rhomboid groups (major and minor), also assist in movement of the scapula and the trapezius also acts as a stabilizer of the scapula. The biceps brachii also will aid in stabilization of the shoulder and elbow joints.

So after all this what am i saying..?

Many people can be strength trained for the rings by just training on the rings, but what little bit extra can be done..? And what else other than strengthening of the large groups can be done..?

It comes down to those stabilizers. Now other than training on the rings, additional strength training needs to be done in the gym, but how..? Firstly, barbells must be replaced with dumbbells. Using dumbbells aids in recruitement of the stabilizers of the shoulder girdle and increased stabilizer strength leads to increased prime mover strength. So dumbbell press as opposed to flat bench press would help. Secondly performing normal exercises such as dumbbell curls at differing angles, such as at 30 degrees lateral rotation would increase rotator cuff involvement. Also performing exercises on medicine balls/physio balls or balance boards to increase proprioception (relative awareness of limb position) and greatly increase strength of the stabilizers such as the serratus anterior and rotator cuff group (plyometric push ups on a medicine ball, push ups on balance boards etc...). Using thera bands for the rotator cuff group is also a possible strength aid.

So in addition to simple, standard strength training exercises, simple stabilization added exercises need to be performed to increase performance that little extra.

Here are some links with regards to anatomy and exercises...
http://exrx.net/Lists/ExList/ChestWt.html#anchor682036
http://familydoctor.org/online/famdocen/home/healthy/physical/injuries/265.html
http://www.shoulder-pain-management.com/shoulderrotatorcuffexercises.html
http://www.changingshape.com/exercise/musclecharts/

JJ

Best Time of the Day to Exercise?

You may have noticed the poll we had running this last week or so. Is there science behind the results/preferences of when people prefer to train and exercise? Are certain times of the day better or worse than others? How much do psychological factors, rather than physical reasons, effect when people hit the gym?

There’s pros and cons both ways with regards to AM versus PM exercise and there are a lot of factors that influence specific exercise and its benefits (eg. nutrition, time). Everybody is effected in many ways by a “body clock” / circadian rhythm. This is an important mechanism for hormone release, activation of electrical activity in muscle, etc. This will have an effect on peoples’ exercise and training times. For example, many elderly folks prefer to exercise early in the morning, as they rise earlier, with an altered circadian rhythm and sleep patterns.

Mornings are generally better for exercise when trying to lose weight. One advantage of morning exercise is an elevated Resting Metabolic Rate (metabolism) through the day. This is accompanied by a phenomenon known as EPOC (Excess Post-exercise Oxygen Consumption) which can promote further fat loss over time. People that exercise in the morning also tend to have higher levels of adherence to exercise/training programs. Many ‘early birds’ also feel their mood is improved from the start of their day.
Some of us just aren’t “morning people” though and should rather find a time of day that we feel better about exercising. Mornings are also often accompanied by lower blood glucose, not so good for any weight/anaerobic training. Injuries are more common with morning training; body temperature is lower, flexibility is decreased and co-ordination with complex exercise techniques will be affected. Morning exercise has been shown to have a slightly higher risk of heart attack or stroke.

Two hormones that play a roll in exercise are Cortisol and Testosterone. Cortisol, a catabolic (breakdown) hormone, is highest within the body in the morning and decreases throughout the day. Testosterone, the main anabolic (build up) hormone, reaches its highest levels, relative to Cortisol, in the afternoon/evening.

Studies have shown that maximal strength reaches highest levels only after midday, with anaerobic and endurance ability peaking in the afternoon. This links with the higher anabolic hormone (Testosterone and Growth Hormone) state within the body to make afternoon/evening exercise slightly better for endurance, muscle mass and strength training. Body temperature rises steadily throughout the day, which makes sports performance generally better during late afternoon/evening. Exercise, especially at gyms, does tend to be more social in the afternoon and evenings too.
Exercising regularly in the PM does tend to be more difficult to maintain for some people as work commitments or distractions can interfere, although dealing with the day’s stress can be an added benefit of exercising at this time. Sleep is not generally affected by exercise, so evening exercise should be fine for most people.

Remember though, any exercise is better than no exercise at all.
Jed