One Foot In Front Of The Other

According to many, the thing that really sets human beings apart from the rest of the natural world is our mastery of locomotion; the ability to move faster, further and with heavier loads than any other creature typically does (never mind that our historical method of doing this was strapping several other animals to a large heap of wood and nails) across every medium our planet has to throw at us; land, sky, sea, snow, whatever. Nowadays, this concept has become associated with our endeavours in powered transport (cars, aeroplanes and such), but the story of human locomotion begins with a far more humble method of getting about that I shall dedicate today’s post to; walking.

It is thought that the first walkers were creatures that roughly approximate to our modern-day crustaceans; the early arthropods. In the early days of multicellular life on earth, these creatures ruled the seas (where all life had thus far been based) and fossils of the time show a wide variety of weird and wonderful creatures. The trilobites that one can nowadays buy as tourist souvenirs in Morocco are but one example; the top predators of the time were massive things, measuring several metres in length with giant teeth and layers of armour plate. All had bony exoskeletons, like the modern insects that are their descendants, bar a few small fish-like creatures a few millimetres in length who had developed the first backbones; in time, the descendants of these creatures would come to dominate life on earth. Since it was faster and allowed a greater range of motion, most early arthropods swam to get about; but others, like the metre-long Brontoscorpio (basically a giant underwater scorpion) preferred the slightly slower, but more efficient, idea of walking about on the seabed. Here, food was relatively plentiful in the form of small ‘grazers’ and attempting to push oneself through the water was wasteful of energy compared to trundling along the bottom. However, a new advantage also presented itself before too long; these creatures were able to cross land over short distances to reach prey- by coincidence, their primitive ‘lungs’ (that collected dissolved oxygen from water in much the same fashion as modern fish gills, but with a less fragile structure) worked just as well at harvesting oxygen from air as water, enabling them to survive on land. As plant life began to venture out onto land to better gain access to the air and light needed to survive, so the vertebrates (in the form of early amphibians) and arthropods began to follow the food, until the land was well and truly colonised by walking life forms.

Underwater, walking was significantly easier than on land; water is a far more dense fluid than air (hence why we can swim in the former but not the latter), and the increased buoyancy this offered meant that early walkers’ legs did not have to support so much of their body’s weight as they would do on land. This made it easier for them to develop the basic walking mechanic; one foot (or whatever you call the end of a scorpion’s leg) is pressed against the ground, before being held stiff and solid as the rest of the body is rotated around it’s joint, moving the creature as a whole forward slightly as it pivots. In almost all invertebrates, and early vertebrates, the creature’s legs are positioned at the side of the body, meaning that as the creature walks they tend to swing from side to side. Invertebrates typically partially counter this problem by having a lot of legs and stepping them in such an order to help them travel in a constant direction, and by having multi-jointed legs that can flex and translate the lateral components of motion into more forward-directed movement, preventing them from swinging from side to side. However, this doesn’t work so well at high speed when the sole priority is speed of movement of one’s feet, which is why most reconstructions of the movement of vertebrates circa 300 million years ago (with just four single-jointed legs stuck out to the side of the body) tends to show their body swinging dramatically from side to side, spine twisting this way and that.  This all changed with the coming of the dinosaurs, whose revolutionary evolutionary advantage was a change in construction of the hip that allowed their legs to point underneath the body, rather than sticking out at the side. Now, the pivoting action of the leg produces motion in the vertical, rather than horizontal direction, so no more spine-twisting mayhem. This makes travelling quickly easier and allows the upper body to be kept in a more stable position, good for striking at fleeing prey, as well as being more energy efficient. Such an evolutionary advantage would soon prove so significant that, during the late Triassic period, it allowed dinosaurs to completely take over from the mammal-like reptiles who had previously dominated the world. It would take more than 150 million years, a hell of a lot of evolution and a frickin’ asteroid to finally let these creatures’ descendants, in the form of mammals, finally prevail over the dinosaurs (by which time they had discovered the whole ‘legs pointing down’ trick).

When humankind were first trying to develop walking robots in the mid-twentieth century, the mechanics of the process were poorly understood, and there are a great many funny videos of prototype sets of legs completely failing. These designers had been operating under the idea that the role of the legs when walking was not just to keep a body standing up, but also to propel them forward, each leg pulling on the rest of the body when placed in front. However, after a careful study of new slow-motion footage of bipedal motion, it was realised that this was not the case at all, and we instead have gravity to thank for pushing us forward. When we walk, we actually lean over our frontmost foot, in effect falling over it before sticking our other leg out to catch ourselves, hence why we tend to go face to floor if the other leg gets caught or stuck. Our legs only really serve to keep us off the ground, pushing us upwards so we don’t actually fall over, and our leg muscles’ function here is to simply put each foot in front of the other (OK, so your calves might give you a bit of an extra flick but it’s not the key thing). When we run or climb, our motion changes; our legs bend, before our quadriceps extend them quickly, throwing us forward. Here we lean forward still further, but this is so that the motion of our quads is directed in the forward, rather than upward direction. This form of motion is less energy efficient, but covers more ground. This is the method by which we run, but does not define running itself; running is simply defined as the speed at which every step incorporates a bit of time where both feet are off the ground. Things get a little more complicated when we introduce more legs to the equation; so for four legged animals, such as horses, there are four footspeeds. When walking there are always three feet on the ground at any one time, when trotting there are always two, when cantering at least one, and when galloping a horse spends the majority of its time with both feet off the ground.

There is one downside to walking as a method of locomotion, however. When blogging about it, there isn’t much of a natural way to end a post.

Advertisement

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.

Who needs a gym?

This is a post I’ve been trying not to resort to in a while- not because I think the content’s going to be bad or anything, just that it’s a bit of a leap from my usual stuff and because it’s actually going to be a bit too easy. However, given the fact that a) the Euros, Wimbledon and the Olympics are all on over the next month or so, b) my last few posts have been of a sporting persuasion, c) I vaguely know what I’m talking about here and d) I keep forgetting my other ideas, I thought I’d bite the bullet and go for it. So here it is, my first ever advice column for this blog: how to get fit and strong without the use of any gym equipment.

Fitness can be broadly (and fairly inadequately) split into three separate fields: aerobic & cardiovascular, muscular and flexibility. I’ll deal with all three of these separately, and am almost certainly going to have to add another post to fit all of the ‘muscular’ area into, but I’ll start with flexibility.

Some would argue that flexibility is not really part of fitness, and it’s true that, on the surface, it doesn’t appear to fit into our typical classification of the subject. However, it is just as much a matter of our physical ability to perform as any other, and thus probably has the right to be included as part of this list. The main reason I have misgivings about talking about it is simply personal knowledge- I don’t really know any exercises designed to improve flexibility.

However, that doesn’t mean I can’t offer advice on the matter. The first, and simplest, way to improve general flexibility and range of motion is just to get active. Every movement of the joints, be they legs, arms, back or wherever, makes them that tiny bit freer to move over that range and thus a little bit more supple- running, cycling, whatever. It is partly for this reason too that it is important to warm up and stretch prior to exercise- by extending the muscles longer than they are naturally used to, then they are prepared for that greater range of movement and are thus capable of easily moving across the more limited range that general exercise demands. Perhaps the easiest ‘flexibility exercise’ one can do is tree climbing  (which also happens to be endlessly entertaining if you can find some good trees), but stuff like yoga can be learnt without too much difficulty from the internet if you’re serious about improving your flexibility. Otherwise, I would suggest joining an appropriate club. Doesn’t have to be yoga or gymnastics or anything quite so extensive- martial arts (my personal preference, and a superb full-body endurance exercise) and rock climbing (which will build forearms and biceps the size of Mercury) are great for teaching your body a whole new way of moving, and are also a lot more fun for the casual enthusiast.

OK, now onto something I can actually talk about with some authority: aerobic and cardiovascular fitness. The goal when training cardio is simply to get the heart pumping- cardiac muscle works like any other muscle in that it can be built by straining it, breaking muscle fibres and having the body re-knit them into a bigger, stronger structure capable of doing more. Cardiovascular training should ideally be done at a rate upwards of 160 bpm (heartbeats per minute), but if you’re struggling to get into exercising then it’s best to start off with a more casual workout. Regular walking can quickly burn off excess fat and build up at least preliminary fitness (although be warned- to be most effective one should aim for a rate of around 120 steps per minute, or less if you’re struggling to keep that pace up, for at least 20 minutes. Bring an iPod too stave off boredom). The average resting heart rate of a person is somewhere around 70bpm- if yours is anything below 80 or so (measure it at home by counting the number of thumps on the left of one’s chest over the space of a minute) and you’re relatively serious about getting fit, then it’s best to step up a gear.

Just about any activity that gets the heart racing (remember- 160bpm minimum, 180 as a target) is suitable for increasing cardio fitness, be it running, cycling, swimming, rowing, football, rugby or whatever else you can think of- the only important thing is to try and keep the motion fast. Running or cycling on a machine (if you have access to one) will make it easier to keep up a pace (since air resistance is decreased), but reduces your workload, meaning less muscle is built on the legs and the effectiveness of the exercise is reduced, meaning you have to work out for longer. Rowing is an especially good exercise for both you muscles and your cardio, but access to a machine can be problematic. Oh, and a word of warning about swimming- whilst it’s a great full-body workout and can really improve your speed, it’s only going to be as effective as a good run or cycle if done at a fast pace, for quite a long time; moderate speeds won’t cut it.

You don’t have to judge one’s activity by heartbeat, as this can be understandably tricky if you’re pounding along a road, but learn to get a feel for your intensity levels. A low intensity, when you’re still able to comfortably breathe and speak (so about up to a fast walk), is a little too slow for proper aerobic work- moderate, where you can feel the breath coming hard but can still speak about normally, is fine for aerobic work over sets of about 20 minutes or longer- but keep going for as long as you can/have the time for. High-intensity work is you going flat out, where speaking becomes next to impossible. It’s probably best left until you’ve achieved a good level of fitness, but if you can manage it then just short bursts of less than 8 minutes (which is about how long you should be able to keep it up) just a few times a week can reap rewards.

A final thing about cardio, before I devote Wednesday’s post to the nitty gritty of muscular workouts- it’s at its most enjoyable when done as part of a sport. Pounding round the roads on a daily jog is almost certainly going to be a more effective workout, and if you’re really looking to seriously improve your fitness then it’s probably more the way to go- but the attraction can quickly fall away in the face of a damp Wednesday when you’re nursing a calf strain. But sport is without a doubt the best way to build up a good level of fitness and strength, make a few mates and have some fun in the process. Some are better than others- boxing is the single best activity for anyone after a cardiovascular workout, whilst something like golf doesn’t really count as exercise- but there’s something for everyone out there, if you know where to look.

Now, to plan a muscular workout for next time…