A kick out of technology

They may not turn you into a Thierry Henry or a Fabio Cannavaro but the latest football boots from the world’s leading manufacturers are packed with enough technology to help any weekend footballer bend it like Beckham.

Look at Adidas’s latest iteration of its well-established Predator model, the Powerswerve. Crafted from kangaroo skin – the lightest, thinnest and strongest leather for a sports shoe – the new model features a tube containing powdered tungsten, one of the heaviest metals, running the length of the outsole. When the player runs normally, the powder is distributed along the floor of the tube. When the player draws back a foot to kick, the powder slides to the front of the boot, adding 40g of extra weight to the “sweet spot”, the point of maximum impact.

Or consider Nike’s concept boot, the Mercurial SL, constructed almost entirely from carbon fibre and said to be the lightest, fastest football boot ever made. A size nine shoe weighs just 190g. Technologies more usually associated with the aerospace and automobile industries were called into play to bond the seven layers of the sole. Nike’s researchers at Montebelluna, Italy, developed a technique for weaving unyielding carbon fibre into a soft and flexible upper. The pattern of the cleats or studs moulded into the one piece outsole is designed for rapid acceleration. Only 2,000 pairs have been made but they point the way to the boot of the future.

Spending on research and development by Adidas, Nike and their competitors runs into hundreds of millions of dollars each year, a sizeable chunk of that going on football boots, balls and strip. Why? Of all recognised sports, isn’t football the one least in need of high technology? Don’t kids kicking around a cheap ball on a patch of wasteland have just as much fun as the professional and enthusiastic amateurs at whom the kit makers are aiming their expensively developed products?

The answer, of course, is a qualified yes. But manufacturers are driven as much by the desire to give their customers competitive advantage through technology as to make money. Chris Walsh of Adidas says: “Technology is at the heart of everything Adidas has done. It has always been a case of designing the product to help the athlete perform.” Nike’s Phil Dickinson claims: “The thing we’ve brought to the sport is a consideration for the performance benefits the athletes are looking for.”

These convictions translate into research programmes involving players at every level and university research departments. Adidas worked with the biomechanics department of the University of Freiburg in developing the Predator. Nike worked with colour scientists to develop a ball that can be seen clearly under floodlighting against the green of the pitch and the distractions of the crowd. It is bright yellow with, counterintuitively, an asymmetric dark blue pattern.

The principal conclusions from the wealth of data generated by this research are somewhat similar for all manufacturers. So both Adidas and Nike agree that the design of the outsole and the arrangement of the studs are critical in helping the player accelerate over the all-important first 10 metres from a standing start.

On a conventional boot, studs are arranged symmetrically on the outsole; the new designs feature asymmetric patterns that are better matched to the part of the foot in contact with the ground as the player gathers speed. And studs these days bear no resemblance to the stubby cylinders of yesteryear. Sleek and streamlined to penetrate and exit the ground more rapidly, they can be popped out to suit different playing conditions in seconds. The makers call the outsole and studs combined “traction systems” and the new designs are said significantly to reduce the load on a player’s knees and ankles.

Nike offers three boot types, each with a style of play and player in mind: the Mercurial Vapor is for speed merchants like Cristiano Ronaldo; the Tiempo is a classic design for wizards of dribble like Cesc Fàbregas; while the Total 90 is for players who demand accuracy and control such as Cannavaro who, incidentally, prefers synthetic materials to leather in his boots. “If you don’t work in football day in, day out it may be surprising to learn that different people want different kit,” says Dickinson.

Each manufacturer has its own special features. Adidas incorporates “smart foam” around the sweet spot, the top of the instep and forefoot, which most players use to take a shot at goal. The foam changes behaviour with use. If the player shoots at goal, the foam compresses then returns the compression energy adding power to the shot. If the player traps the ball, energy is absorbed, helping to kill its motion. Adidas’s most technically advanced boot, the Tunit F50+, can be put together in 52 different ways to suit a player’s preferences.

“Everything,” Walsh says, “is about customisation.” Youngsters want to tailor their boots to their own liking – a different colour on each foot if they wish.

The lightness and flexibility of the modern boot, however, has led some to question whether it provides enough protection for the player. Critics point to the metatarsal injuries that threatened David Beckham’s career before the 2002 World Cup and Wayne Rooney’s before the 2006 event. It is a criticism the manufacturers reject robustly, pointing out that there is no statistical evidence of any increase in broken bones since the boots were introduced. On the other hand, improvements in sports medicine – and a voracious media culture – mean that cracks and breaks are reported more frequently than before. The game and the pitches on which it is played are faster and harder, and players train and compete more intensively.

Gerard Hartmann, a physiotherapist who works with a range of leading athletes and is an adviser to Nike, says: “It’s my view and that of sports medicine generally that it’s not the footwear but the demands placed on athletes, be they footballers or whoever. The twisting, turning and pivoting movements make football a very intense game and it’s like anything­ – if you keep bending a wire hanger it will be OK 20 times, and then snap the 21st time you do it.”

Modern balls weigh the same as their leather forerunners but are constructed in a different way. A conventional ball is made from 32 flat panels stitched together to form a sphere. The Adidas match ball to be used in next year’s European tournament is

constructed from 14 panels of thermoplastic polyurethane, each of which has been preformed as a spherical segment. The panels are thermally sealed together and the surface is dimpled like a golfball to maximise flight and accuracy and to increase the time the ball is in contact with the foot.

Nike’s equivalent has microgrooves in the outer casing and nitrogen-expanded foam as one of four layers designed to give the ball its stability and ability to store and release energy.

All the top manufacturers produce shirts and shorts designed to keep players cool and comfortable. They are designed and cut in three dimensions for a better fit. Man-made fibres, which “wick” sweat away from the body and aid its evaporation from the surface, are extensively used in Nike’s DriFit outerware together with venting panels to keep the players cool.

Kit is getting tighter – partly to prevent opponents from grabbing a handful of shirt but also to provide support for the muscles. Thermoplastic polyurethane finds another use in Adidas’s Techfit underware where bands of the material provide support for hamstrings and hold the chest open to help breathing.

No matter how advanced the playing equipment, football is traditionally a game at the mercy of the weather. Overturning tradition means laying an artificial pitch, such as the one used at Moscow’s Luzhniki stadium.

Once little more than green carpet laid on concrete, today’s artificial pitches from companies such as FieldTurf Tarkett, the market leader, are created from thousands of filaments of green polyester sewn into a base layer.

Professional players say that the surface is slower than grass and can demand better ball control skills. The company is still working to increase the resilience and durability of the filaments and ways of recycling the turf at the end of its life.