Running science keeps us on our toes

It’s not the fall that hurts, but the sudden stop at the end. Scientists in the United States, Kenya and Scotland say this is also true for our feet when we run.

Recent research, published in the international science journal Nature by Leiberman and colleagues, compares foot strike patterns and vertical collision forces in habitually barefoot runners and runners who wear shoes.

There are three types of foot strike patterns in runners. Runners who strike the ground heel-first are called rear-foot strike (RFS) runners. Those who land on the ball of their foot are fore-foot strike (FFS) runners and those who strike simultaneously with their heel and the ball of their foot are mid-foot strike (MFS) runners.

It seems that foot strike pattern largely determines the vertical force experienced by a runner every time they hit the ground. It has to do with the biomechanics of the leg and the foot, and the conversion of translational force (the runner’s body moving up and down) into rotational force around the ankle.

In FFS runners, the calf acts like a spring during impact and some of the downwards force of the body is converted into rotational energy around the ankle joint. This means that much of the runner’s body mass can decelerate gradually rather than suddenly. In RFS runners, impact occurs just below the ankle and little downwards force can be converted to rotational energy, leaving a greater amount of body mass to decelerate quickly during foot strike. This results in a vertical force in RFS runners that is approximately three times higher than in FFS runners.

Furthermore, it appears that running shoes are influencing our foot strike patterns. Runners who normally run barefoot usually FFS or MFS. Runners who normally wear shoes tend to RFS.

Modern running shoes have an elevated cushioned heel to make RFS running more comfortable. However, running shoes may encourage RFS running. Foot strike patterns in a group of habitually-shod runners were recorded before and after six weeks of training in conditions to simulate barefoot running (no or minimal footwear). The proportion of RFS runners in the group decreased from 72% to 36% after barefoot running training.

This research has important implications for running-related injuries. Some members of the running community are staunch advocates of the benefits of barefoot running, and this research may support some of their claims. It is somewhat disconcerting, however, to find that this research was in part funded by Vibram USA, the designers of the new FiveFingers® footwear that aims to imitate barefoot running. We wait in anticipation of a controlled study, funded by bodies other than footwear companies, to compare the incidence of injuries among FFS, MFS and RFS runners, in shoes and barefoot.

Leiberman et al. (2010). Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature. 463:531-535.

World Cup soccer exposed as fake: Fans deluded

I’m a keen soccer fan, and since retiring from playing the game two years ago with injuries, I’ve taken up watching my boyfriend play on the weekend for the All Age 2 side at Sydney University.

I’m usually one of two or three supporters that turn up to watch the boys play – usually one of the younger guys’ dads and maybe a girlfriend of one of the players. Interestingly if there is a girl sitting on the sideline, it’s always someone different each week. My conversations with a few of these girls make me realise that I’m one of very few people who regularly watches park soccer – willingly, at least. The rapid turnover of fans for the AA2s suggest to me that most supporters begrudgingly meet their quota of attending one game per season, and that’s generally one game too many. I personally really enjoy having a front row seat to an always entertaining game of local social soccer. I will admit though that the minute-by-minute, player-by-player analysis of the game on the way home in the car can get slightly tedious.

But recently I’m struggling to fulfill my duty as the faithful spectator at these games. My attention wanders and I get distracted. Suddenly it is far more interesting to tear up blades of grass and sleep in the sun than watch the beautiful drama unfold in front of me. What’s wrong with me? Don’t I care about soccer anymore?

What’s wrong is that I’m suffering a case of World Cup delusion. Every four years soccer fans are bombarded with images and footage of soccer freaks from around the world. Men with fitness and skill so extraordinary that they make gravity-defying moves look effortless. In park soccer, the moments that make you gasp come not from feats of skill but feats that defy physics or all probability – most notably when you have to cover your mouth to stop yourself from yelling “How the %*$# did you miss that!” After seeing such well-oiled, perfectly drilled teams on TV, watching games where the ball spends more time stuck in trees or out on the road than on the pitch is quite a shock to the system.

So if I can get more than my fill of ridiculously good games from the comfort of the couch, what’s the point of making the trek halfway across Sydney, in weekend traffic, to sit on cold hard ground in bone chilling wind to watch amateur soccer?

The point is that World Cup soccer, and all professional soccer for that matter, is a fantasy world that in no way resembles the reality of the world game. The vast majority of soccer players around the world do not get paid tens of thousands of dollars to simply roll out of bed in the morning and rock up to training. Your average weekend warrior certainly does not get round-the-clock access to free physio treatment and massage or free boots and gear from their sponsors, nor do they play with the roundest ball ever manufactured on perfectly manicured pitches.

The reality of soccer is far more interesting and entertaining if you make the effort to go and watch it.

After navigating their way to an obscure field somewhere out in the Sydney ‘burbs, the weekend warrior turns their gaze to the pitch. You may not know that the pitch is an important factor to take into account when devising tactics for each game. Players should aim to keep any slide tackles or falling over to a minimum on concrete-like pitches. Make a spectacular slide on your knees to celebrate a goal like they do in the world cup and you will be rewarded with a spectacular hospital bill for your knee reconstruction. The more experienced in the team make mental notes of the sprinkler heads and ankle-twisting divots in the playing surface.

Commentators have been raving about the technology behind the playing surfaces at this year’s world cup – an impressive hybrid of natural grass and artificial turf to strengthen the field. Apparently no one has told them that this technology has been used on Sydney pitches for years. As the weekend warriors will attest, most Sydney soccer fields have at least some percentage of artificial turf, usually in the form of an Astroturf cricket pitch right across the middle of the field. Some Sydney councils kindly cover these cricket pitches during the soccer season with a two-foot high mound of top soil, forcing all play to the edges of the field and leaving centre midfielders picking clods of dirt out of their studs for days.

Nevertheless, the weekend warriors pull on their boots, using sufficient electrical tape to keep their toes from coming out the split that develops, without fail, along the inner seam of their shoes. These broken bravehearts are an innovative lot, devising imaginative methods to strap up dodgy knees and weak ankles and developing entirely new uses for heat cream. Broken legs and gushing wounds from head clashes can always be treated with water from someone’s drink bottle on the sideline. I’m still waiting for this all-curing “magic elixir” to be snapped up by pharmaceutical companies.

Weekend warriors are resourceful too. Three shirts that have the number “8” on the back? Some quick thinking and those guys have turned two of them into “18” and “81” with their trusty electrical tape. And it seems like these shirts are always recycled, lovingly salvaged from mythical soccer teams full of blokes sized XX-large (I’ve never understood why soccer clubs buy their jerseys so bloody big!).

Refs have a tough and thankless job and let me tell you, they’re not doing it for the money! But there has been a lot of dissatisfaction about the standard of refereeing this world cup. The Socceroos in particular are crying that they’ve been hard done by in their two games so far against Germany and Ghana. I reckon they should send some of our very talented local Sydney refs over to South Africa. Our referees are so good that they can accurately make offside calls without linesman and from the relative comfort of the centre circle. Unbelievable (yes, really)!

So get up off the couch and go and watch the weekend warrior you know play the game they love, even with the odds stacked against them in every way. You won’t have to put up with those awful vuvuzelas either!

Tahu offended by Johns' "black c***" remark

The unceremonious departure of Andrew Johns from the Blues origin camp earlier this week after making a racist slur about Queensland winger Greg Inglis was met with a unanimous call to address an underlying culture of racism in rugby league. Timana Tahu handed in his Blues guernsey in protest over the slur and has received full support from the likes of ex-player Anthony Mundine, Gold Coast full back Preston Campbell and Maroons coach Mal Meninga.

In a dressing room pep talk, Johns called Inglis a “black c***” and referred to himself as “white trailer trash from Cessnock”. Johns has emphasized that his comments were just banter to fire up the Blues squad and that there was no malice intended. Johns has expressed his remorse about his choice of language to the press and has apologized to Tahu in person.

I think that Joey's comments were probably made in jest. But the fact of the matter is that Johns’ comments were inappropriate and inexcusable, irrespective of their context. Regardless of your intentions, coaches and managerial staff need to avoid any language that could be interpreted as racist or discriminatory in any way. There are definitely better ways to motivate your players than making insulting remarks about the other team.

Nevertheless I find the irony of this media frenzy amusing. To clarify, I find nothing amusing about racism or Johns’ comments. Rather I am intrigued by which part of Johns’ slur that Tahu and others have found offensive, especially when some players’ respect for women has been called into question in the not so distant past. Most women find the word “c***” particularly insulting, but I don’t see any Blues players giving up their spot in the team in protest over this part of Johns’ remark.

While rugby league goes back into damage control to address perceived racism in the sport, perhaps it should also take a good hard look at their re-education programs that encourage players to respect women. If league is serious about improving its public image, coaches and managers need to lead by example and re-education needs to start from the top. Respect for people of different genders and races needs to come not only from the players but also the coaching and managerial staff who mentor them.