Fish

‘Fish’ is one of my favourite words. Having only a single syllable means it can be dropped into conversation without a second thought, thus enabling one to cause maximum confusion with minimal time spent considering one’s move, which often rather spoils the moment. The very… forward nature of the word also suits this function- the very bluntness of it, its definitive end and beginning with little in the way of middle to get distracting, almost forces it to take centre stage in any statement, whether alone or accompanied by other words, demanding it be said loud and proud without a trace of fear or embarrassment. It also helps that the word is very rarely an appropriate response to anything, enhancing its inherent weirdness.

Ahem. Sorry about that.

However, fish themselves are very interesting in their own right; and yes, I am about to attempt an overall summary of one of the largest groups in the animal kingdom in less than 1000 words.  For one thing, every single vertebrate on the planet is descended from them; in 1999 a fossil less than 3cm long and 524 million years old was discovered in China with a single ‘stick’ of rigid material, probably cartilage, running down the length of its body. It may be the only example ever discovered of Myllokunmingia fengjiaoa (awesome name), but that tiny little fossil has proved to be among the most significant ever found. Although not proven, that little bit of cartilage is thought to be the first ever backbone, making Myllokunmingia the world’s first fish and the direct ancestor of everything from you to the pigeon outside your window. It’s quite a humbling thought.

This incredible age of fish as a group, which in turn means there are very few specimens of early fish, has meant that piscine evolution is not studied as a single science; the three different classes of fish (bony, cartilaginous and jawless, representing the likes of cod, sharks and hagfish respectively- a fourth class of armoured fish died out some 360 million years ago) all split into separate entities long before any other group of vertebrates began to evolve, and all modern land-based vertebrates (tetrapods, meaning four-limbed) are direct descendants of the bony fish, the most successful of the three groups. This has two interesting side-effects; firstly that a salmon is more closely related to you than to a shark, and secondly (for precisely this reason) that some argue there is no such thing as a fish. The term ‘fish’ was introduced as a coverall term to everything whose lack of weight-bearing limbs confines them to the water before evolutionary biology had really got going, and technically the like of sharks and lamprey should each get a name to themselves- but it appears we’re stuck with fish, so any grumpy biologists are just going to have to suck it.

The reason for this early designation of fish in our language is almost certainly culinary in origin, for this is the main reason we ever came, and indeed continue to come, into contact with them at all. Fish have been an available, nutritious and relatively simple to catch food source for humans for many a millennia, but a mixture of their somewhat limited size, the fact that they can’t be farmed and the fact that bacon tastes damn good meant they are considered by some, particularly in the west (fish has always enjoyed far greater popularity in far eastern cultures), to the poor cousins to ‘proper meat’ like pork or beef. Indeed, many vegetarians (including me; it’s how I was brought up) will eschew meat but quite happily eat fish in large quantities, usually using the logic that fish are so damn stupid they’re almost vegetables anyway. Vegetarians were not, however, the main reason for fish’s survival as a common food for everyone, including those living far inland, in Europe- for that we can thank the Church. Somewhere in the dim and distant past, the Catholic Church decreed that one should not eat red meat on the Sabbath day- but that fish was permitted. This kept fish a common dish throughout Europe, as well as encouraging the rampant rule bending that always accompanies any inconvenient law; beaver were hunted almost to extinction in Europe by being classed as fish under this rule. It was also this ruling that lead to lamprey (a type of jawless fish that looks like a cross between a sea snake and a leech) becoming a delicacy among the crowned heads of Europe, and Henry I of England (third son of William the Conqueror, in case you wanted to know) is reported to have died from eating too many of the things.

The feature most characteristic of fish is, of course, gills, even though not all fish have them and many other aquatic species do (albeit less obviously). To many, how gills work is an absolute mystery, but then again how many of you can say, when it comes right down to the science of the gas exchange process, how your lungs work? In both systems, the basic principle is the same; very small, thin blood vessels within the structure concerned are small and permeable enough to allow gas molecules to move across the gap from one side of the blood vessel’s wall to the other, allowing carbon dioxide built up from moving and generally being alive to move out of the bloodstream and fresh oxygen to move in. The only real difference concerns structure; the lungs consist of a complex, intertwining labyrinth of air spaces of various size with blood vessels spread over the surface and designed to filter oxygen from the air, whilst gills basically string the blood vessels up along a series of sticks and hold them in the path of flowing water to absorb the oxygen dissolved within it- gills are usually located such that water flows through the mouth and out via the gills as the fish swims forward. In order to ensure a constant supply of oxygen-rich water is flowing over the gills, most fish must keep swimming constantly or else the water beside their gills would begin to stagnate- but some species’, such as nurse sharks, are able to pump water over their gills manually, allowing them to lie still and allow them to do… sharky things. Interestingly, the reason gills won’t work on land isn’t simply that they aren’t designed to filter oxygen from the air; a major contributory factor is the fact that, without the surrounding water to support them, the structure of the gills is prone to collapse, causing parts of it cease to be able to function as a gas exchange mechanism.

Well, that was a nice ramble. What’s up next time, I wonder…

Once Were Hairy

Aesthetically, humans are somewhat standout from the rest of natural creation. We are multicellular organisms, instantly making us completely different to the vast majority of the species’ currently on earth today, and warm-blooded, differentiating us from every plant, fungi, invertebrate, fish, amphibian and reptile. We stand on two legs, but at the same time cannot fly, differentiating us from almost every species of bird and mammal. But this is only so much basic classification; the one trait that aesthetically differentiates from nearly all of these is our hairlessness. Brian May excepted.

Technically, there are other members of the order mammalia who go without fur; the simultaneously cute and horrifying naked mole rat is but one land-borne example, and no swimming mammal (whales, dolphins etc.) have fur. And yes, we technically do have a full layer of fur covering us, meaning that you have more hairs (in terms of number, rather than volume) than a chimpanzee- but our hairy covering is so small as to be practically not there, and the amount of insulation and protection that it provides is minimal. Across most of our body, the only natural protection we have against our enemies and the elements is our bare skin.

Exactly why this is the case is somewhat unclear, because fur is very useful stuff. It offers a surprising degree of protection against cuts and attacks, and is just as effective at keeping out the elements, be they cold, wind or rain. Length can and does vary widely depending on location and need, and many species (including some humans) have incorporated their fur as a form of bodily decoration to attract mates and intimidate rivals; the lion’s mane is the most obvious example.

Also confusing is why we have hair where we do; upon our heads and around the pubic regions. It is thought that hair on the head may be either an almost vestigial thing, left over from the days when our ancestors did have hair, although this theory doesn’t explain why it remained on our head. Better explanations include the slight degree of extra shielding it provides to our brain, our greatest evolutionary advantage, or because the obviousness of the head makes it a natural point for us to rig our hair into elaborate, ceremonial styles and headdresses, raising the social standing of those who are able to get away with such things and helping them attract a mate and further their genes. However, the pubic region is of particular interest to evolutionary biologists, in part because hair there seems counter-productive; the body keeps the testicles outside the body because they need to be kept slightly cooler than the body’s interior temperature in order to keep sperm count high and ensure fertility (an interesting side effect of which is that people who take regular hot baths tend to have a lower sperm count). Surrounding such an area with hair seems evolutionarily dumb, reducing our fertility and reducing our chances of passing our genes onto the next generation. It is however thought that hair around these regions may aid the release of sexual pheremones, helping us to attract a mate, or that it may have helped to reduce chafing during sex and that women tended to choose men with pubic hair (and vice versa) to make sex comfortable. This is an example of sexual selection, where evolution is powered by our sexual preferences rather than environmental necessity, and this itself has been suggested as a theory as to why we humans lost our hair in the first place, or at least stayed that way once we lost it; we just found it more attractive that way. This theory was proposed by Charles Darwin, which seems odd given the truly magnificent beard he wore. However, the ‘chafing’ theory regarding pubic hair is rather heavily disputed from a number of angles, among them the fact that many couples choose to shave their pubic region in order to enhance sexual satisfaction. Our preferences could, of course, have changed over time.

One of the more bizarre theories concerning human hairlessness is the ‘aquatic apes’ theory; it is well known that all swimming mammals, from river dolphins to sea lions, favour fat (or ‘blubber’) in place of fur as it is more streamlined and efficient for swimming and is better for warmth underwater. Therefore, some scientists have suggested that humans went through a period of evolution where we adopted a semi-aquatic lifestyle, fishing in shallow waters and making our homes in and around the water. They also point to the slight webbing effect between our fingers as evidence of a change that was just starting to happen before we left our waterborne lifestyle, and to humanity’s ability to swim (I am told that if a newborn baby falls into water he will not sink but will instinctively ‘swim’, an ability we lose once we become toddlers and must re-learn later, but I feel it may be inappropriate to test this theory out). However, there is no evidence for these aquatic apes, so most scientists feel we should look elsewhere.

Others have suggested that the reason may have been lice; one only needs to hear the horror stories of the First World War to know of the horrible-ness of a lice infestation, and such parasites are frequently the vectors for virulent diseases that can wipe out a population with ease. Many animals spend the majority of their time picking through their fur to remove them (in other apes this is a crucial part of social bonding), but if we have no fur then the business becomes infinitely simpler because we can actually see the lice. Once again, adherents point to sexual selection- without hair we can display our untarnished, healthy, parasite-free skin to the world and our prospective mates (along with any impressive scars we want to show off), allowing them to know they are choosing a healthy partner, and this may go some way to explaining why the ultimate expression of male bodily beauty is considered a strong, hairless chest and six-pack, symbolising both strength and health. Ironically, a loss of fur and our subsequent use of clothes developed an entire new species; the body louse lives only within the folds of our clothes, and was thought to have evolved from hair lice some 50,000 years ago (interestingly, over a million years passed between our African ancestors passing through the hairless phase and our use of clothes, during which time we diverged as a species from Neanderthals, discovered tools and lived through an Ice Age. Must have been chilly, even in Africa). It’s a nice theory, but one considered redundant by some in the face of another; homeostasis.

Apart from our brainpower, homeostasis (or the ability to regulate our body temperature) is humanity’s greatest evolutionary advantage; warm blooded mammals are naturally adept at it anyway, giving us the ability to hunt & forage in all weathers, times and climates, and in cold weather fur provides a natural advantage in this regard. However, without fur to slow the process of heat regulation (sweating, dilation of blood vessels and such all become less effective when insulated by fur) human beings are able to maintain an ambient bodily temperature almost regardless of the weather or climate. African tribesmen have been known to run through the bush for an hour straight and raise their body temperature by less than a degree, whilst our ability to regulate heat in colder climates was enough for scores of Ice Age-era human bones to be found across the then-freezing Europe. Our ability to regulate temperature surpasses even those other ‘naked’ land mammals, the elephant and rhinoceros, thanks to our prominent nose and extremities that allow us to control heat even more precisely. In short, we’re not 100% sure exactly why we humans evolved to be hairless, but it has proved a surprisingly useful trait.

Art vs. Science

All intellectual human activity can be divided into one of three categories; the arts, humanities, and sciences (although these terms are not exactly fully inclusive). Art here covers everything from the painted medium to music, everything that we humans do that is intended to be creative and make our world as a whole a more beautiful place to live in. The precise definition of ‘art’ is a major bone of contention among creative types and it’s not exactly clear where the boundary lies in some cases, but here we can categorise everything intended to be artistic as an art form. Science here covers every one of the STEM disciplines; science (physics, biology, chemistry and all the rest in its vast multitude of forms and subgenres), technology, engineering (strictly speaking those two come under the same branch, but technology is too satisfying a word to leave out of any self-respecting acronym) and mathematics. Certain portions of these fields too could be argued to be entirely self-fulfilling, and others are considered by some beautiful, but since the two rarely overlap the title of art is never truly appropriate. The humanities are an altogether trickier bunch to consider; on one hand they are, collectively, a set of sciences, since they purport to study how the world we live in behaves and functions. However, this particular set of sciences are deemed separate because they deal less with fundamental principles of nature but of human systems, and human interactions with the world around them; hence the title ‘humanities’. Fields as diverse as economics and geography are all blanketed under this title, and are in some ways the most interesting of sciences as they are the most subjective and accessible; the principles of the humanities can be and usually are encountered on a daily basis, so anyone with a keen mind and an eye for noticing the right things can usually form an opinion on them. And a good thing too, otherwise I would be frequently short of blogging ideas.

Each field has its own proponents, supporters and detractors, and all are quite prepared to defend their chosen field to the hilt. The scientists point to the huge advancements in our understanding of the universe and world around us that have been made in the last century, and link these to the immense breakthroughs in healthcare, infrastructure, technology, manufacturing and general innovation and awesomeness that have so increased our quality of life (and life expectancy) in recent years. And it’s not hard to see why; such advances have permanently changed the face of our earth (both for better and worse), and there is a truly vast body of evidence supporting the idea that these innovations have provided the greatest force for making our world a better place in recent times. The artists provide the counterpoint to this by saying that living longer, healthier lives with more stuff in it is all well and good, but without art and creativity there is no advantage to this better life, for there is no way for us to enjoy it. They can point to the developments in film, television, music and design, all the ideas of scientists and engineers tuned to perfection by artists of each field, and even the development in more classical artistic mediums such as poetry or dance, as key features of the 20th century that enabled us to enjoy our lives more than ever before. The humanities have advanced too during recent history, but their effects are far more subtle; innovative strategies in economics, new historical discoveries and perspectives and new analyses of the way we interact with our world have all come, and many have made news, but their effects tend to only be felt in the spheres of influence they directly concern- nobody remembers how a new use of critical path analysis made J. Bloggs Ltd. use materials 29% more efficiently (yes, I know CPA is technically mathematics; deal with it). As such, proponents of humanities tend to be less vocal than those in other fields, although this may have something to do with the fact that the people who go into humanities have a tendency to be more… normal than the kind of introverted nerd/suicidally artistic/stereotypical-in-some-other-way characters who would go into the other two fields.

This bickering between arts & sciences as to the worthiness/beauty/parentage of the other field has lead to something of a divide between them; some commentators have spoken of the ‘two cultures’ of arts and sciences, leaving us with a sect of sciences who find it impossible to appreciate the value of art and beauty, thinking it almost irrelevant compared what their field aims to achieve (to their loss, in my opinion). I’m not entirely sure that this picture is entirely true; what may be more so, however, is the other end of the stick, those artistic figures who dominate our media who simply cannot understand science beyond GCSE level, if that. It is true that quite a lot of modern science is very, very complex in the details, but Albert Einstein was famous for saying that if a scientific principle cannot be explained to a ten-year old then it is almost certainly wrong, and I tend to agree with him. Even the theory behind the existence of the Higgs Boson, right at the cutting edge of modern physics, can be explained by an analogy of a room full of fans and celebrities. Oh look it up, I don’t want to wander off topic here.

The truth is, of course, that no field can sustain a world without the other; a world devoid of STEM would die out in a matter of months, a world devoid of humanities would be hideously inefficient and appear monumentally stupid, and a world devoid of art would be the most incomprehensibly dull place imaginable. Not only that, but all three working in harmony will invariably produce the best results, as master engineer, inventor, craftsman and creator of some of the most famous paintings of all time Leonardo da Vinci so ably demonstrated. As such, any argument between fields as to which is ‘the best’ or ‘the most worthy’ will simply never be won, and will just end up a futile task. The world is an amazing place, but the real source of that awesomeness is the diversity it contains, both in terms of nature and in terms of people. The arts and sciences are not at war, nor should they ever be; for in tandem they can achieve so much more.

3500 calories per pound

This looks set to be the concluding post in this particular little series on the subject of obesity and overweightness. So, to summarise where we’ve been so far- post 1: that there are a lot of slightly chubby people present in the western world leading to statistics supporting a massive obesity problem, and that even this mediocre degree of fatness can be seriously damaging to your health. Post 2: why we have spent recent history getting slightly chubby. And for today, post 3: how one can try to do your bit, especially following the Christmas excesses and the soon-broken promises of New Year, to lose some of that excess poundage.

It was Albert Einstein who first demonstrated that mass was nothing more than stored energy, and although the theory behind that precise idea doesn’t really correlate with biology the principle still stands; fat is your body’s way of storing energy. It’s also a vital body tissue, and is not a 100% bad and evil thing to ingest, but if you want to lose it then the aim should simply be one of ensuring that one’s energy output, in the form of exercise  exceeds one’s energy input, in the form of food. The body’s response to this is to use up some of its fat stores to replace this lost energy (although this process can take up to a week to run its full course; the body is a complicated thing), meaning that the amount of fat in/on your body will gradually decrease over time. Therefore, slimming down is a process that is best approached from two directions; restricting what’s going in, and increasing what’s going out (both at the same time is infinitely more effective than an either/or process). I’ll deal with what’s going in first.

The most important point to make about improving one’s diet, and when considering weight loss generally, is that there are no cheats. There are no wonder pills that will shed 20lb of body fat in a week, and no super-foods or nutritional supplements that will slim you down in a matter of months. Losing weight is always going to be a messy business that will take several months at a minimum (the title of this post refers to the calorie content of body fat, meaning that to lose one pound you must expend 3500 more calories than you ingest over a given period of time), and unfortunately prevention is better than cure; but moping won’t help anyone, so let’s just gather our resolve and move on.

There is currently a huge debate going on concerning the nation’s diet problems of amount versus content; whether people are eating too much, or just the wrong stuff. In most cases it’s probably going to be a mixture of the two, but I tend to favour the latter answer; and in any case, there’s not much I can say about the former beyond ‘eat less stuff’. I am not a good enough cook to offer any great advice on what foods you should or shouldn’t be avoiding, particularly since the consensus appears to change every fortnight, so instead I will concentrate on the one solid piece of advice that I can champion; cook your own stuff.

This is a piece of advice that many people find hard to cope with- as I said in my last post, our body doesn’t want to waste time cooking when it could be eating. When faced with the unknown product of one’s efforts in an hours time, and the surety of a ready meal or fast food within five minutes, the latter option and all the crap that goes in it starts to seem a lot more attractive. The trick is, therefore, to learn how to cook quickly- the best meals should either take less than 10-15 minutes of actual effort to prepare and make, or be able to be made in large amounts and last for a week or more. Or, even better, both. Skilled chefs achieve this by having their skills honed to a fine art and working at a furious rate, but then again they’re getting paid for it; for the layman, a better solution is to know the right dishes. I’m not going to include a full recipe list, but there are thousands online, and there is a skill to reading recipes; it can get easy to get lost between a long list of numbers and a complicated ordering system, but reading between the lines one can often identify which recipes mean ‘chop it all up and chuck in some water for half an hour’.

That’s a very brief touch on the issue, but now I want to move on and look at energy going out; exercise. I personally would recommend sport, particularly team sport, as the most reliably fun way to get fit and enjoy oneself on a weekend- rugby has always done me right. If you’re looking in the right place, age shouldn’t be an issue (I’ve seen a 50 year old play alongside a 19 year old student at a club rugby match near me), and neither should skill so long as you are willing to give it a decent go; but, sport’s not for everyone and can present injury issues so I’ll also look elsewhere.

The traditional form of fat-burning exercise is jogging, but that’s an idea to be taken with a large pinch of salt and caution. Regular joggers will lose weight it’s true, but jogging places an awful lot of stress on one’s joints (swimming, cycling and rowing are all good forms of ‘low-impact exercise’ that avoid this issue), and suffers the crowning flaw of being boring as hell. To me, anyway- it takes up a good chunk of time, during which one’s mind is so filled with the thump of footfalls and aching limbs that one is forced to endure the experience rather than enjoy it. I’ll put up with that for strength exercises, but not for weight loss when two far better techniques present themselves; intensity sessions and walking.

Intensity sessions is just a posh name for doing very, very tiring exercise for a short period of time; they’re great for burning fat & building fitness, but I’ll warn you now that they are not pleasant. As the name suggest, these involve very high-intensity exercise (as a general rule, you not be able to talk throughout high-intensity work) performed either continuously or next to continuously for relatively short periods of time- an 8 minute session a few times a week should be plenty. This exercise can take many forms; shuttle runs (sprinting back and forth as fast as possible between two marked points or lines), suicides (doing shuttle runs between one ‘base’ line and a number of different lines at different distances from the base, such that one’s runs change in length after each set) and tabata sets (picking an easily repeatable exercise, such as squats, performing them as fast as possible for 20 seconds, followed by 10 seconds of rest, then another 20 seconds of exercise, and so on for 4-8 minute) are just three examples. Effective though these are, it’s difficult to find an area of empty space to perform them without getting awkward looks and the odd spot of abuse from passers-by or neighbours, so they may not be ideal for many people (tabata sets or other exercises such as press ups are an exception, and can generally be done in a bedroom; Mark Lauren’s excellent ‘You Are Your Own Gym’ is a great place to start for anyone interested in pursuing this route to lose weight & build muscle). This leaves us with one more option; walking.

To my mind, if everyone ate properly and walked 10,000 steps per day, the scare stats behind the media’s obesity fix would disappear within a matter of months. 10,000 steps may seem a lot, and for many holding office jobs it may seem impossible, but walking is a wonderful form of exercise since it allows you to lose oneself in thought or music, whichever takes your fancy. Even if you don’t have time for a separate walk, with a pedometer in hand (they are built into many modern iPods, and free pedometer apps are available for both iPhone and Android) and a target in mind (10k is the standard) then after a couple of weeks it’s not unusual to find yourself subtly changing the tiny aspects of your day (stairs instead of lift, that sort of thing) to try and hit your target; and the results will follow. As car ownership, an office economy and lack of free time have all grown in the last few decades, we as a nation do not walk as much as we used to. It’s high time that changed.

Why the chubs?

My last post dealt with the thorny issue of obesity, both it’s increasing presence in our everyday lives, and what for me is the underlying reason behind the stats that back up media scare stories concerning ‘the obesity epidemic’- the rise in size of the ‘average’ person over the last few decades. The precise causes of this trend can be put down to a whole host of societal factors within our modern age, but that story is boring as hell and has been repeated countless times by commenters far more adept in this field than me. Instead, today I wish present the case for modern-day obesity as a problem concerning the fundamental biology of a human being.

We, and our dim and distant ancestors of the scaly/furry variety, have spent the last few million years living wild; hunting, fighting and generally acting much like any other evolutionary pathway. Thus, we can learn a lot about our own inbuilt biology and instincts by studying the behaviour of animals currently alive today, and when we do so, several interesting animal eating habits become apparent. As anyone who has tried it as a child can attest (and I speak from personal experience), grass is not good stuff to eat. It’s tough, it takes a lot of chewing and processing (many herbivores have multiple stomachs to make sure they squeeze the maximum nutritional value out of their food), and there really isn’t much of it to power a fully-functional being. As such, grazers on grass and other such tough plant matter (such as leaves) will spend most of their lives doing nothing but guzzle the stuff, trying to get as much as possible through their system. Other animals will favour food with a higher nutritional content, such as fruits, tubers or, in many cases, meat, but these frequently present issues. Fruits are highly seasonal and rarely available in a large enough volume to support a large population, as well as being quite hard to get a lot of down; plants try to ‘design’ fruits so that each visitor takes only a few at a time, so as best to spread their seeds far and wide, and as such there are few animals that can sustain themselves on such a diet.  Other food such as tubers or nuts are hard to get at, needing to be dug up or broken in highly energy-consuming activities, whilst meat has the annoying habit of running away or fighting back whenever you try to get at it. As anyone who watches nature documentaries will attest, most large predators will only eat once every few days (admittedly rather heavily).

The unifying factor of all of this is that food is, in the wild, highly energy- and time-consuming to get hold of and consume, since every source of it guards its prize jealously. Therefore, any animal that wants to survive in this tough world must be near-constantly in pursuit of food simply to fulfil all of its life functions, and this is characterised by being perpetually hungry. Hunger is a body’s way of telling us that we should get more food, and in the wild this constant desire for more is kept in check by the difficulty that getting hold of it entails. Similarly, animal bodies try to assuage this desire by being lazy; if something isn’t necessary, then there’s no point wasting valuable energy going after it (since this will mean spending more time going after food to replace lost energy.)

However, in recent history (and a spectacularly short period of time from evolution’s point of view), one particular species called homo sapiens came up with this great idea called civilisation, which basically entailed the pooling and sharing of skill and resources in order to best benefit everyone as a whole. As an evolutionary success story, this is right up there with developing multicellular body structures in terms of being awesome, and it has enabled us humans to live far more comfortable lives than our ancestors did, with correspondingly far greater access to food. This has proved particularly true over the last two centuries, as technological advances in a more democratic society have improved the everyman’s access to food and comfortable living to a truly astounding degree. Unfortunately (from the point of view of our waistline) the instincts of our bodies haven’t quite caught up to the idea that when we want/need food, we can just get food, without all that inconvenient running around after it to get in the way. Not only that, but a lack of pack hierarchy combined with this increased availability means that we can stock up on food until we have eaten our absolute fill if so we wish; the difference between ‘satiated’ and ‘stuffed’ can work out as well over 1000 calories per meal, and over a long period of time it only takes a little more than we should be having every day to start packing on the pounds. Combine that with our natural predilection to laziness meaning that we don’t naturally think of going out for some exercise as fun purely for its own sake, and the fact that we no longer burn calories chasing our food, or in the muscles we build up from said chasing, and we find ourselves consuming a lot more calories than we really should be.

Not only that, but during this time we have also got into the habit of spending a lot of time worrying over the taste and texture of our food. This means that, unlike our ancestors who were just fine with simply jumping on a squirrel and devouring the thing, we have to go through the whole rigmarole of getting stuff out of the fridge, spending two hours slaving away in a kitchen and attempting to cook something vaguely resembling tasty. This wait is not something out bodies enjoy very much, meaning we often turn to ‘quick fixes’ when in need of food; stuff like bread, pasta or ready meals. Whilst we all know how much crap goes into ready meals (which should, as a rule, never be bought by anyone who cares even in the slightest about their health; salt content of those things is insane) and other such ‘quick fixes’, fewer people are aware of the impact a high intake of whole grains can have on our bodies. Stuff like bread and rice only started being eaten by humans a few thousand years ago, as we discovered the benefits of farming and cooking, and whilst they are undoubtedly a good food source (and are very, very difficult to cut from one’s diet whilst still remaining healthy) our bodies have simply not had enough time, evolutionarily speaking, to get used to them. This means they have a tendency to not make us feel as full as their calorie content should suggest, thus meaning that we eat more than our body in fact needs (if you want to feel full whilst not taking in so many calories, protein is the way to go; meat, fish and dairy are great for this).

This is all rather academic, but what does it mean for you if you want to lose a bit of weight? I am no expert on this, but then again neither are most of the people acting as self-proclaimed nutritionists in the general media, and anyway, I don’t have any better ideas for posts. So, look at my next post for my, admittedly basic, advice for anyone trying to make themselves that little bit healthier, especially if you’re trying to work of a few of the pounds built up over this festive season.

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.

Drunken Science

In my last post, I talked about the societal impact of alcohol and its place in our everyday culture; today, however, my inner nerd has taken it upon himself to get stuck into the real meat of the question of alcohol, the chemistry and biology of it all, and how all the science fits together.

To a scientist, the word ‘alcohol’ does not refer to a specific substance at all, but rather to a family of chemical compounds containing an oxygen and hydrogen atom bonded to one another (known as an OH group) on the end of a chain of carbon atoms. Different members of the family (or ‘homologous series’, to give it its proper name) have different numbers of carbon atoms and have slightly different physical properties (such as melting point), and they also react chemically to form slightly different compounds. The stuff we drink is that with two carbon atoms in its chain, and is technically known as ethanol.

There are a few things about ethanol that make it special stuff to us humans, and all of them refer to chemical reactions and biological interactions. The first is the formation of it; there are many different types of sugar found in nature (fructose & sucrose are two common examples; the ‘-ose’ ending is what denotes them as sugars), but one of the most common is glucose, with six carbon atoms. This is the substance our body converts starch and other sugars into in order to use for energy or store as glycogen. As such, many biological systems are so primed to convert other sugars into glucose, and it just so happens that when glucose breaks down in the presence of the right enzymes, it forms carbon dioxide and an alcohol; ethanol, to be precise, in a process known as either glycolosis (to a scientist) or fermentation (to everyone else).

Yeast performs this process in order to respire (ie produce energy) anaerobically (in the absence of oxygen), so leading to the two most common cases where this reaction occurs. The first we know as brewing, in which an anaerobic atmosphere is deliberately produced to make alcohol; the other occurs when baking bread. The yeast we put in the bread causes the sugar (ie glucose) in it to produce carbon dioxide, which is what causes the bread to rise since it has been filled with gas, whilst the ethanol tends to boil off in the heat of the baking process. For industrial purposes, ethanol is made by hydrating (reacting with water) an oil by-product called ethene, but the product isn’t generally something you’d want to drink.

But anyway, back to the booze itself, and this time what happens upon its entry into the body. Exactly why alcohol acts as a depressant and intoxicant (if that’s a proper word) is down to a very complex interaction with various parts and receptors of the brain that I am not nearly intelligent enough to understand, let alone explain. However, what I can explain is what happens when the body gets round to breaking the alcohol down and getting rid of the stuff. This takes place in the liver, an amazing organ that performs hundreds of jobs within the body and contains a vast repetoir of enzymes. One of these is known as alcohol dehydrogenase, which has the task of oxidising the alcohol (not a simple task, and one impossible without enzymes) into something the body can get rid of. However, most ethanol we drink is what is known as a primary alcohol (meaning the OH group is on the end of the carbon chain), and this causes it to oxidise in two stages, only the first of which can be done using alcohol dehydrogenase. This process converts the alcohol into an aldehyde (with an oxygen chemically double-bonded to the carbon where the OH group was), which in the case of ethanol is called acetaldehyde (or ethanal). This molecule cannot be broken down straight away, and instead gets itself lodged in the body’s tissues in such a way (thanks to its shape) to produce mild toxins, activate our immune system and make us feel generally lousy. This is also known as having a hangover, and only ends when the body is able to complete the second stage of the oxidation process and convert the acetaldehyde into acetic acid, which the body can get rid of relatively easily. Acetic acid is commonly known as the active ingredient in vinegar, which is why alcoholics smell so bad and are often said to be ‘pickled’.

This process occurs in the same way when other alcohols enter the body, but ethanol is unique in how harmless (relatively speaking) its aldehyde is. Methanol, for example, can also be oxidised by alcohol dehydrogenase, but the aldehyde it produces (officially called methanal) is commonly known as formaldehyde; a highly toxic substance used in preservation work and as a disinfectant that will quickly poison the body. It is for this reason that methanol is present in the fuel commonly known as ‘meths’- ethanol actually produces more energy per gram and makes up 90% of the fuel by volume, but since it is cheaper than most alcoholic drinks the toxic methanol is put in to prevent it being drunk by severely desperate alcoholics. Not that it stops many of them; methanol poisoning is a leading cause of death among many homeless people.

Homeless people were also responsible for a major discovery in the field of alcohol research, concerning the causes of alcoholism. For many years it was thought that alcoholics were purely addicts mentally rather than biologically, and had just ‘let it get to them’, but some years ago a young student (I believe she was Canadian, but certainty of that fact and her name both escape me) was looking for some fresh cadavers for her PhD research. She went to the police and asked if she could use the bodies of the various dead homeless people who they found on their morning beats, and when she started dissecting them she noticed signs of a compound in them that was known to be linked to heroin addiction. She mentioned to a friend that all these people appeared to be on heroin, but her friend said that these people barely had enough to buy drink, let alone something as expensive as heroin. This young doctor-to-be realised she might be onto something here, and changed the focus of her research onto studying how alcohol was broken down by different bodies, and discovered something quite astonishing. Inside serious alcoholics, ethanol was being broken down into this substance previously only linked to heroin addiction, leading her to believe that for some unlucky people, the behaviour of their bodies made alcohol as addictive to them as heroin was to others. Whilst this research has by no means settled the issue, it did demonstrate two important facts; firstly, that whilst alcoholism certainly has some links to mental issues, it is also fundamentally biological and genetic by nature and cannot be solely put down as the fault of the victim’s brain. Secondly, it ‘sciencified’ (my apologies to grammar nazis everywhere for making that word up) a fact already known by many reformed drinkers; that when a former alcoholic stops drinking, they can never go back. Not even one drink. There can be no ‘just having one’, or drinking socially with friends, because if one more drink hits their body, deprived for so long, there’s a very good chance it could kill them.

Still, that’s not a reason to get totally down about alcohol, for two very good reasons. The first of these comes from some (admittely rather spurious) research suggesting that ‘addictive personalities’, including alcoholics, are far more likely to do well in life, have good jobs and overall succeed; alcoholics are, by nature, present at the top as well as the bottom of our society. The other concerns the one bit of science I haven’t tried to explain here- your body is remarkably good at dealing with alcohol, and we all know it can make us feel better, so if only for your mental health a little drink now and then isn’t an all bad thing after all. And anyway, it makes for some killer YouTube videos…