Explainer: how to win a Tour de France sprint

By Bryce Dyer, Senior Lecturer in Product Design

The final dash to the line in a Tour de France sprint finish may appear to the bystander to be a mess of bodies trying to cram into the width of a road, but there is a high degree of strategy involved. It takes tactics, positioning and, ultimately, power.

The perfect sprint

In a perfect race, the best execution of a sprint win does not always come down to one rider. It is often the result of the work of teammates too. The back story to a winning sprint may have started hours before the finish line is in sight.

Jack Bauer in tears after the agonising stage 15 finish
Yoan Valat/EPA

During the stage, riders who have little chance in the finale will try their luck to beat the pack by being part of a “breakaway” – they jump clear of the peloton and then hope to outrun the others to the line. But if any team wants the stage to end in a mass sprint, it will check the speed of this breakaway and typically calculate how quickly the riders in it could be reeled in. Catch them too soon and new attacks may go clear (meaning more work for the interested teams to chase down), leave it too late and the breakaway wins. In stage 15, this approach got tested when New Zealand rider Jack Bauer spent all day in the breakaway. He finally was caught just 20 metres from the finish line by the sprinters. The sport can sometimes be very cruel.

Commentators typically suggest that on flat terrain, the ideal controllable gap is roughly one minute per 10 kilometres between a breakaway and the chasing pack. Towards the end of a stage, the interested teams supply riders to power into the wind and slowly close this gap down. The breakaway should then hopefully be caught with a handful of kilometres left to go.

At this point, the sprint-orientated teams deploy what is known as a leadout “train”. This train is made up of as many riders as possible from the same team. Each team member on the front then rides at a maximum effort before peeling off. The team’s designated sprinter is at the back of this train and is intentionally sheltered by the efforts of those riding in front to save his energy. It has been demonstrated that with four cyclists riding in a line, a rider positioned four men back only has to produce 64% of the power of the rider at the very front.

Mark Cavendish and Mark Renshaw execute the perfect lead out and sprint on the Champs Elysee in 2009
Guillaume Horcajuelo/EPA

If the leadout pace is high, the racing will be fast enough to discourage any late attacks from other riders. When viewing overhead TV footage, if the speed is high, the head of the main pack will have a pointed arrowhead-like shape to it. If the speed is at its highest though, you’ll see the peloton instead strung out into a very long, thin line. This is hard work for everyone but actually provides a safer and more controllable path for the riders through the final kilometres.

The penultimate rider in a sprint train is referred to as the leadout. This person puts in the last effort to position the sprinter sheltering behind. Ideally, the sprinter is then finally only exposed at the front with around 200 metres to go. When this happens, a winning sprinter like Mark Cavendish will cover this final portion in around 11 seconds.

Freelancing

If a sprinter doesn’t have the use of a leadout train – which does happen – he can “freelance”. This makes the opposition teams do the work before the sprinter leapfrogs around the group, hopefully ending up directly behind another sprinter with enough time to beat him to the finish line. In this case, a sprinter from one team effectively becomes the leadout for another.

On some occasions, no single team is able to control the final run to the line at all. From the air, the shape of the peleton in this case becomes broad at the front and spread across the full width of the road. When this happens, the chances of crashes are higher as rival leadout trains jostle for position and riders leap from wheel to wheel looking for shelter.

First week desperation

The first stage of this year’s Tour de France was unusual as it was likely going to result in a bunch sprint. The first rider past the post would not only get a stage win for their team but would also get to wear the yellow jersey as overall leader. With such a prestigious prize on the line, this meant more riders were involved and willing to take the risks, ramping up the chances for a crash.

Crashes normally occur when riders touch the wheels of other riders around them or lose control of their bicycles. In stage one this year, aggression played a part as Mark Cavendish and Australian Simon Gerrans battled to follow the wheel of Slovakian sprinter Peter Sagan. Sometimes riders realise they have nowhere to go and have to delay their sprint or wait for a gap to open up. Some opt for more punchy tactics though, using shoulders, elbows or heads to force gaps to open up between them and other riders. In stage one, Cavendish was boxed in, tried to force his way out and took both men down.

One of the most dramatic examples of a sprint crash is the first stage in the 1994 event when a policeman who was manning the finish straight barriers decided to lean out to take a photo of the finish.

Video The 1994 crash

But he underestimated both how fast and how close the riders were to him. Belgian Wilfried Nelissen (who had his head down) crashed into him and was thrown nearly 50 metres down the road with multiple broken bones. Another competitor, Frenchman Laurent Jalabert took the crash full-force in the face and his bicycle was destroyed in the impact.

Ultimately the perfect sprinter is a rider who expends as little energy as possible on the day, is deposited by others in the right place at the right time and has the ability to make fast judgement calls as the shape of the peloton changes around them. Marcel Kittel and his Giant Shimano team have shown everyone else how it’s done so far in 2014, but the prestige sprint stage on the Champs Élysées this weekend will give his rivals (Cavendish excepted) a final chance to put the theory into practice.

The Conversation

Bryce Dyer does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation.
Read the original article.

From one man and his bike to the hi-tech peleton: the changing face of the Tour de France

By Bryce Dyer, Senior Lecturer in Product Design, Faculty of Science & Technology

The Tour de France is one of the most iconic and physically demanding sporting events in the world. Held annually since 1903, it has evolved from a simple test of endurance and speed to a festival of technology and innovation as teams fight to find the edge that will take them over mountains, high speed straights and cobbled roads ahead of their rivals.

The basic premise of the tour has generally remained the same since 1913 – the rider who covers the route in the least accumulated time across all of the stages wins. But the route is changed by the organisers every year, which means that unique demands are placed on the riders, the teams and their resources.

This year’s tour is divided into 21 stages covering a total of 3,656km. There are nine flat stages, five hilly stages, six mountain stages, one 54km time trial and two rest days. As a result of all these different conditions, an awful lot of specialised equipment is needed. In early tours, the same bike was used for the whole race but these days, a different one is chosen based on the different demands of the stage, its gearing and wheels tailored to the terrain.

Cobble horror

Perhaps the most intriguing test for the teams this year will come on stage five when the riders face some perilous sections of cobbled roads. The tour riders, who generally weigh between 60kg and 80kg, will be subjected to massive levels of impact and vibrations as they pass over these surfaces.

To add to their misery, these cobbled roads have been in place for decades so they are not flat. Wear, breakage and subsidence makes them uneven, to put it mildly. To maximise speed and control, the best riders often ride in the middle or “crown” of these sections. With space at a premium though, experienced riders might also choose to ride in the dirt gutter between the cobbles and the grass banks at the sides of the road which has often been worn smooth.

This decision becomes critical in wet weather in particular, when riding on even the slightest camber can be extremely dangerous at these speeds. Punctures, loss of control and crashes are common and injuries can be severe.

Many of the riders looking to do well in a race like the tour will not typically ride on these kind of surfaces in other events because they are suited to heavier, stronger riders rather than those built for mountainous terrain. There are a small number of early season races in the spring that do feature these kind of surfaces such as the notorious Paris-Roubaix – known as the “Hell of the North” – which give a flavour of what riders can expect.

Paris-Roubaix

To ride these cobbled stages, bicycle frames may use a different geometry when compared to those used on tarmac or asphalt. These bikes may be longer in length to help smooth the ride. Riders will also often use extra padded bar tape and wider tyres to absorb the vibrations and sometimes extra brake levers are added to help them stop quickly in the peloton.

Higher ground

During the hilly and mountain stages, when the race passes through both the Alps and the Pyrenees, the teams will send their riders out on the lightest bikes possible. The lighter a bike is, the faster it will go uphill. A professional rider may be able to generate and sustain 6.4 watts of power per kilogram on a typical alpine climb whereas a recreational rider may only be able to achieve half of that ratio. As a result, the bike’s weight will be as close to the regulation minimum of 6.8kg as possible and lightweight wheels will be used to minimise the impact of rotating mass which could slow a bike’s acceleration when a rider wishes to attack others when on a climb.

Time trial tech

Stage 20 this year will showcase the real importance of cycling aerodynamics. This relatively flat individual time trial will see the riders trying to generate maximum power while minimising aerodynamic drag. Put simply, the more aerodynamic you are, the faster you will go (or the more energy you can save) for the same power.

Bradley Wiggins on a time trial.
Waterboyzoo, CC BY-NC

The bicycles used for this are highly specialised, with filled-in disc rear wheels and low drag frames. The riders themselves will assume a riding style that makes them look a lot like a downhill skier with their arms angled directly in front of their chest and torso to minimise their frontal area. They’ll use aerobars and wear a teardrop shaped helmet to reach speeds that can average 50km an hour.

Staying in touch on level ground

One of the more controversial new technologies in professional cycling has been the use of team radios to relay orders and information during the race. The organisers have even experimented with removing the riders’ earpieces in an effort to add more drama to the racing.

It is true that radio technology is often used to influence the result. Flat terrain typically results in a mass sprint but sometimes a small group of riders will break away at an early point in a stage and try to hold onto the lead until its end. However, these early escapes are rarely successful because the team cars and the riders following the breakaway can calculate the distance between the breakaway group and the “peloton” and then use radio transmitters to determine how fast they need to move to control or close the gap. It’s very hard for the breakaway group, typically containing just a few cyclists, to overcome the horsepower of 200 chasing riders armed with precise knowledge of the wherabouts of their quarry.

Do it yourself

Technology is a major part of the tour these days but that has not always been the case. In the early editions of the event over a hundred years ago, the riders were very much expected to compete alone and be self-sufficient.

Eugène Christophe

When the forks of Eugène Christophe’s bike snapped mid-race in 1913, he had to visit a local blacksmith and then re-weld them himself. It was later discovered that Christophe had enlisted the help of a local boy to pump the bellows for the forge and as a result, he was later penalised for receiving outside assistance.

The use of new developments in cycling technology was frowned upon too. The tour’s organisers didn’t even allow the use of mechanical gear changing systems until 1913. Before this, a rider would have to stop, unbolt their rear wheel and flip it over so they could switch to a single cog mounted on the other side of the hub. In the event of a puncture, they rode with spare tyres looped around their torsos.

Battling bodies and brains

Technology is now, of course, a fundamental part of riding the tour. And it stretches far beyond the bicycles themselves. Preparations for the race will have begun long before the start and the clothing riders wear, the bicycles they ride and the nutrition they take are finely honed products that can take months or even years to develop.

When they’re not actually riding, recovery technology is used to prepare them for the next stage. Riders will have massages, wear compression clothing and take ice baths to help reduce muscle soreness and inflammation. The key principle here is that winners are not always the strongest but those who possibly tire the least over the three weeks.

Each team of riders is supported by doctors, mechanics, physiologists, coaches and operational management. There are multiple team cars and buses which house their equipment and spares. They become, in effect, a mobile business and garage for the duration of the race.

Professional bike racing has been referred to as “chess on wheels” as the smartest rider and team, not the strongest, often win. We’ll find out if this is the case this year from July 5.

The Conversation

Bryce Dyer does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation.
Read the original article.

Bryce Dyer discusses Paralympic tech for The Conversation

Bryce Dyer, Senior Lecturer in Product Design at Bournemouth University wrote a feature article for The Conversation discussing some of the technology used in the Winter Paralympic Games.

Dyer stated, “Technology has long been a part of sport. Every event, whether it’s cycling, sailing or skiing requires uniquely designed technology. Over in Sochi right now, athletes are showcasing the greatest of innovations being pushed to the limits of their design.”

A number of innovative solutions have been created to assist competitors such as; Bluetooth headsets for the visually impaired, sophisticated sit ski’s where a seat is mounted to a single ski, and electro-acoustic headphones to effectively “aim” by listening to a tone that varies in pitch as they move their gun on target.

One of the newest additions to this year’s Winter Paralympics is snowboarding. For this event, specialised prosthetic limbs have been developed using linkages and pneumatic springs to help absorb impacts, but allowing “competitors to perform manoeuvres without being restricted by weight and mobility”.

“The Paralympic Games showcases novel sports that require innovative solutions to get the best from athletes, be it through engineering, wireless technology or adaptation of traditional equipment.”

Bryce Dyer wins Isambard Kingdom Brunel award at British Science Festival

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Bryce Dyer gave the prestigious Isambard Kingdom Brunel award lecture to a full house at this year’s British Science Festival.

The lecture, entitled ‘Prosthesis, Disability and the role of Technology in Elite Sport’, gave an illuminating account of the work that Bryce Dyer has been conducting at Bournemouth University.

The lecture went into detail about the use of prosthetics in sport, more specifically Olympic and Paralympic disciplines, the types of prostesis available, and the advantages and disadvantages of using such technology.

Mr Dyer joins the ranks of previous award lecturers such as Professor Brian Cox, Professor Richard Wiseman, and Dr Maggie Aderin-Pocock.

After the lecture, Dyer, a senior lecturer in Product Design at BU, was awarded a certificate by the British Science Association to mark the occasion.

After the lecture Bryce Dyer said, “The feeling is one of immense satisfaction, to take what we have been working on for a few years and transfer that knowledge to an enthusiastic audience.”

Bryce continued, “You only have to look at the names  of people who have won this award before to know that it has real credibility and, as an academic, it gives me an immense sense of self-satisfaction. I don’t think in my wildest dreams I dreamt of giving the award lecture at an event like this. To be involved in a Festival of such history is a great experience.”

Bryce also appeared at the chat-show style cafe ‘The Exchange’ where he gave an overview of the subject area to the listening diners.

Bryce was not the only Bournemouth University staff member to make an appearance at the Festival, with BU’s Outreach and Liaison team also running daily workshops with local children to teach them about some of the work taking place at Bournemouth University.

The following blog post has more information about Bryce Dyer’s Award Lecture or you could read the story on the British Science Association website.

Isambard Kingdom Brunel Award lecture date for BU prosthetics expert

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The prestigious Isambard Kingdom Brunel Award lecture is to be delivered by Bournemouth University’s Bryce Dyer for his research and work with prosthetics at the British Science Festival 2013.

Mr Dyer joins the ranks of previous award lecturers such as Professor Brian Cox, Professor Richard Wiseman, and Dr Maggie Aderin-Pocock.

Each year, five academics from across the UK are selected to take part in the Award Lecture series, with each lecture encompassing a different area of science.

The Isambard Kingdom Brunel Award focuses on the fields of engineering, technology and industry. Mr Dyer will present “Prosthesis, disability and the role of technology in elite sport”.

The lecture will reveal the colourful history of limb prostheses, and progress into how they have been engineered to not only complete, but also to compete in physical challenges today.

Mr Dyer will examine the controversy surrounding the use of such technology in competitive sport, following the debates off the back the London 2012 Games, and look at what could be done to address such problems in the future.

The British Science Festival takes place in Newcastle from 7-12 September 2013 and is one of Europe’s largest celebrations of science, engineering and technology, with over 250 events, activities, exhibitions and trips taking place over a week in September, in a different location every year.

Mr Dyer said, “I am delighted to have this opportunity, and am looking forward to presenting this research. The British Science Festival is a unique opportunity to share scientific findings with the public, and it is an honour to be selected to give the Award Lecture.”

Bryce Dyer to be honoured at British Science Festival

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Bryce Dyer, Senior Lecturer in Product Design at Bournemouth Univesity, has been selected for the prestigious honour of delivering an Award Lecture, at the 2013 British Science Festival, which will be taking place in Newcastle from 7-12 September.

Bryce Dyer will deliver the Isambard Kingdom Brunel Award Lecture, and joins the ranks of previous award lecturers such as Professor Brian Cox, Professor Richard Wiseman, and Dr Maggie Aderin-Pocock.

Each year, five academics from across the UK are selected to take part in the Award Lecture series, with each lecture encompassing a different area of science.

The Isambard Kingdom Brunel Award focuses on the fields of engineering, technology and industry. Mr Dyer will present “Prosthesis, disability and the role of technology in elite sport”.

The lecture will reveal the colourful history of limb prostheses, and progress into how they have been engineered to not only complete, but also to compete in physical challenges today.

Mr Dyer will examine the controversy surrounding the use of such technology in competitive sport, following the debates off the back the London 2012 Games, and look at what could be done to address such problems in the future.

Finally, the lecture will examine how such technology attempts to restore the function of amputated limbs to people like elite athletes or the armed forces and ultimately how such innovations may change the face of both disability and sport as we currently recognise it in the very near future.

The British Science Festival is one of Europe’s largest celebrations of science, engineering and technology, with over 250 events, activities, exhibitions and trips taking place over a week in September, in a different location every year.

The programme of events offers something for everyone, with activities for families and schools groups, teens, adults, and stimulating debate for anyone interested in the latest research.

Mr Dyer said, “I am delighted to have this opportunity, and am looking forward to presenting this research. The British Science Festival is a unique opportunity to share scientific findings with the public, and it is an honour to be selected to give the Award Lecture.”

Bryce Dyer talks about advances in prosthetics on BMA website

Bryce Dyer, senior lecturer in Product Design at BU, commented on the potential implications of human enhancement for an article on the BMA website.

A recent Royal Society report has explored how advances in science and technology could allow people to work longer into old age and return to work quicker after illness.

“Look at it in the same way as mobile phones,” said Bryce.

“Ten years ago they were like bricks but they’ve become cheaper, easier to produce and more available over time. The same will happen with prosthesis.”

He also raised concerns about with genetic engineering, which could correct faults in an embryo and enhance it physically or mentally.

“We could make someone super-intelligent but it could have catastrophic effects for society. The lines between natural and artificial and technological could blur.

“At the moment we let nature take its course, but as time goes on we can affect nature and attempt to control and manipulate it.”

Bryce’s primary research interest is with the application and development of technology within sport, and he predicts a dramatic improvement over the next 10 years, which could see it used to enhance function rather than just restore performance.

But, he adds, we must treat technology with care.

“It could become a race between engineers and surgeons instead of sports people. The concept of what it is to be human could change.”

You can read the full article here.