The Science of Iron

I have mentioned before that I am something of a casual gymgoer- it’s only a relatively recent hobby, and only in the last couple of months have I given any serious thought and research to my regime (in which time I have also come to realise that some my advice in previous posts was either lacking in detail or partially wrong- sorry, it’s still basically useful). However, whilst the internet is, as could be reasonably expected, inundated with advice about training programs, tips on technique & exercises to work different muscle groups (often wildly disagreeing with one another), there is very little available information concerning the basic science behind building muscle- it’s just not something the average gymgoer knows. Since I am fond of a little research now and then, I thought I might attempt an explanation of some of the basic biology involved.

DISCLAIMER: I am not a biologist, and am getting this information via the internet and a bit of ad libbing, so don’t take this as anything more than a basic guideline

Everything in your body is made up of tiny, individual cells, each a small sac consisting of a complex (and surprisingly ‘intelligent’) membrane, a nucleus to act as its ‘brain’ (although no-one is entirely sure exactly how they work) and a lot of watery, chemical-y stuff called cytoplasm squelching about and reacting with things. It follows from this that to increase the size of an organ or tissue requires these cells to do one of two things; increase in number (hyperplasia) or in size (hypertrophy). The former case is mainly associated with growths such as neoplasia (tumours), and has only been shown to have an impact on muscles in response to the injection of growth hormones, so when we’re talking about strength, fitness and muscle building we’re really interested in going for hypertrophy.

Hypertrophy itself is still a fairly broad term biologically, and only two aspects of it are interesting from an exercise point of view; muscular and ventricular hypertrophy. As the respective names suggest, the former case relates to the size of cells in skeletal muscle increasing, whilst the latter is concerned with the increase in size & strength of the muscles making up the walls of the heart (the largest chambers of which are called the ventricles). Both are part of the body’s long-term response to exercise, and for both the basic principle is the same- but before I get onto that, a quick overview of exactly how muscles work may be in order.

A muscle cell (or muscle fibre) is on of the largest in the body, vaguely tubular in shape and consisting in part of many smaller structures known as myofibrils (or muscle fibrils). Muscle cells are also unusual in that they contain multiple cell nuclei, as a response to their size & complex function, and instead of cytoplasm contain another liquid called sarcoplasm (more densely packed with glycogen fuel and proteins to bind oxygen, and thus enabling the muscles to respire more quickly & efficiently in response to sudden & severe demand). These myofibrils consist of multiple sections called myofilaments, (themselves made of a family of proteins called myosins) joined end-to-end as repeating units known as sarcomeres. This structure is only present in skeletal, rather than smooth muscle cells (giving the latter a more regular, smoothly connected structure when viewed under the microscope, hence the name) and are responsible for the increased strength available to skeletal muscles. When a muscle fibril receives an electrical impulse from the brain or spinal cord, certain areas or ‘bands’ making up the sarcomeres shrink in size, causing the muscle as a whole to contract. When the impulse is removed, the muscle relaxes; but it cannot extend itself, so another muscle working with it in what is known as an antagonistic pair will have to pull back on it to return it to its original position.

Now, when that process is repeated a lot in a small time frame, or when a large load is placed on the muscle fibre, the fibrils can become damaged. If they are actually torn then a pulled muscle results, but if the damage is (relatively) minor then the body can repair it by shipping in more amino acids (the building blocks of the proteins that make up our bodies) and fuel (glycogen and, most importantly, oxygen). However, to try and safeguard against any future such event causing damage the body does its bit to overcompensate on its repairs, rebuilding the protein structures a little more strongly and overcompensating for the lost fuel in the sarcoplasm. This is the basic principle of muscular hypertrophy; the body’s repair systems overcompensating for minor damage.

There are yet more subdivisions to consider, for there are two main types of muscular hypertrophy. The first is myofibrillated hypertrophy, concerning the rebuilding of the myofibrils with more proteins so they are stronger and able to pull against larger loads. This enables the muscle to lift larger weights & makes one stronger, and is the prominent result of doing few repetitions of a high load, since this causes the most damage to the myofibrils themselves. The other type is sarcoplasmic hypertrophy, concerning the packing of more sarcoplasm into the muscle cell to better supply the muscle with fuel & oxygen. This helps the muscle deal better with exercise and builds a greater degree of muscular endurance, and also increases the size of the muscle, as the increased liquid in it causes it to swell in volume. It is best achieved by doing more repetitions on a lower load, since this longer-term exercise puts more strain on the ability of the sarcoplasm to supply oxygen. It is also advisable to do fewer sets (but do them properly) of this type of training since it is more tiring; muscles get tired and hurt due to the buildup of lactic acid in them caused by an insufficient supply of oxygen requiring them to respire anaerobically. This is why more training on a lower weight feels like harder work, but is actually going to be less beneficial if you are aiming to build muscular strength.

Ventricular (or cardiac) hypertrophy combines both of these effects in a response to the increased load placed on the muscles in the heart from regular exercise. It causes the walls of the ventricles to thicken as a result of sarcoplasmic hypertrophy, and also makes them stronger so that the heart has to beat less often (but more powerfully) to supply blood to the body. In elite athletes, this has another effect; in response to exercise the heart’s response is not so much to beat more frequently, but to do so more strongly, swelling more in size as it pumps to send more blood around the body with each beat. Athletic heart syndrome, where the slowing of the pulse and swelling of heart size are especially magnified, can even be mistaken for severe heart disease by an ill-informed doctor.

So… yeah, that’s how muscle builds (I apologise, by the way, for my heinous overuse of the word ‘since’ in the above explanation). I should point out quickly that this is not a fast process; each successive rebuilding of the muscle only increases the strength of that muscle by a small amount, even for serious weight training, and the body’s natural tendency to let a muscle degrade over time if it is not well-used means that hard work must constantly be put in to maintain the effect of increased muscular size, strength and endurance. But then again, I suppose that’s partly what we like about the gym; the knowledge that we have earned our strength, and that our willingness to put in the hard work is what is setting us apart from those sitting on the sofa watching TV. If that doesn’t sound too massively arrogant.

Part 4… and I think there’s going to be another one…

Part 4 of my series on gym-less workouts should be the last one on that subjects specifically- however, since a related idea has been knocking around my head for a while (since I started this series), I’m going to continue with my running theme of sport n stuffs for at least one more post. Whether I go on for even longer than that is entirely up to whether I can think of enough material for it, and whether I think it’s got boring.

But first, my final two exercises:

FOREARMS
Where:  Er… on your forearms. As in the bit between hand and elbow. Something that not a lot of people know about the forearms is that their main function is not in fact to move the wrist (although they do do that), but to control the hand and fingers (which contain no muscles of their own due to lack of space, but connect to small muscles in the forearm). As such, they are responsible for the strength of your grip.
Exercise: Grip strength is a very important part of a lot of everyday and workout exercises- one of the most common beneficiaries is pull-ups, so doing those will build your forearms a little. However, to work them more specifically (and make pull-ups of all kinds an easier process), you basically need to find a way of gripping something against resistance. If you really want, you can buy these things consisting of two handles with a spring in between them that you clench and unclench, but I’m sticking to non-equipment exercises here. You can just find something to grab hold of and repeatedly clench and unclench against it, but for more satisfying results just take any heavy object with a handle- if you happen to have a shopping bag that does not lacerate your fingers, that’s perfect, but a handle at the top of a rucksack will work too. Hang the handle from outstretched fingers, and simply repeatedly clench and relax your hand. Best of all, this is the kind of thing you can do casually on the way home from the shops, meaning you don’t have to set aside time to work it out. Forearms are perhaps not the most crucial muscle group, but they are useful nonetheless and, given that they are really easy to work, you’d be pretty dumb not to.

FULL BODY
Where: …come on, really? I mean really?
Exercise: Many serious gym-goers don’t really believe in full-body workouts other than as a fitness technique, and next to none would be able to name on for working all of the body’s muscles. This is unsurprising- most people would associate a ‘full-body workout’ either as a descriptive term for a gym session, rather than exercise, or something like swimming, which will work just about every muscle gently, and will mostly only build endurance (although, offset against that, the most physically impressive guy I have ever met set it all off as a swimmer, so if you know what you’re doing…). The thing is, resistance training (using weight as a load) fundamentally doesn’t work more than one or two muscle groups well without technique and effectiveness suffering, and so is not designed for full-body exercises. There is, however, an alternative that is- tension training.
I came across tension training in martial arts, where it is used to train the body to stiffen up when it is hit and thus absorb blows better. It basically consists of performing a range of motions, without any weight, very slowly and controlledly, but working against your own body to provide the load to work against. To explain- muscles work in antagonistic pairs, meaning one contracts to move a joint one way, and its partner contracts to move it in the opposite direction. The principle of tension training is that by tensing both muscles at once, if the joint is to move then the muscle contracting must overcome the force of the other muscle pulling against it, and thus both muscles get worked. Tension training done properly involves performing very slow, simple motions whilst endeavouring to keep every muscle in your body tensed up as you perform the motion.
A key feature of tension training is breathing- you should do long, controlled breaths in time with the motion, breathing out as you contract and perform the stretch (your breath should sound very strained, like a sound effect from some deathly minion in a fantasy film, as it forces its way through your tense neck) and breathing in as you relax and return to position. To use an example, if your chosen motion were a bicep curl, then you would tense up all your muscles (bicep, tricep, chest, back, neck, legs, abdominals, everything) and breathe out in one long, slow, 10 second breath as you contracted the biceps and brought them up to your chest, and then relax and breathe out as you return to your starting position. This strict breathing pattern deprives your body of oxygen, forcing it to learn to use it more efficiently and greatly benefiting your muscular endurance, whilst the exercise itself works muscles for strength (all muscles get a bit of work, but the ones worked hardest are those moving, so the biceps and triceps in the example above). Tension exercises can be incredibly tiring, especially if done at the end of a session (which is probably where they belong to prevent you becoming too tired to do anything else), but are worth the effort for the benefits they can reap- they should take about 3-5 minutes overall, over a variety of motions and exercises (some martial arts incorporate them into a ‘dance’ of strikes and blocks for variety and training), and should provide an interesting line of exercises for everyone from the lowliest newbie trying to fulfil a New Year’s resolution, to the most musclebound hunk who’s in the gym 4 times a week, every week, for the last 5 years. I thoroughly recommend them.