Your sport: American football

As technical as it is physical, American football has been one of the "big three" US sports, alongside baseball and basketball, since its birth over 120 years ago. In recent years, its popularity has also grown in Europe, where Rhein Fire and Frankfurt Galaxy now boast average attendances of more than 40,000.

They play in NFL Europe – a professional offshoot of the National Football League in the US – with four others from across the continent. Since the demise of the London-based Monarchs, Scottish Claymores are now NFL Europe's sole UK team.

Though a cousin of rugby, American football bears little resemblance to that sport. There are 11 players to a team, with a rolling substitution system. The team in possession are called the offense (the American spelling is always used), and attempt to move the ball towards the defense's "end zone" and score a touchdown by crossing the goal line or a field goal by kicking through the posts.

Each play begins with a scrimmage. The ball may be passed forward once per play, and players can block any opponent. The quarterback begins each play at the "snap" of the ball by throwing or handing to a team-mate, or running with the ball himself. All progress is measured in "yardage" on the marked out field or "gridiron". The offensive team try to get as far downfield as they can over the four "downs", or chances, allowed in each attack. If they succeed in advancing 10 yards or more, they are awarded another four chances. A touchdown is worth six points, and an extra point is awarded for a rugby-style kicked coversion, or two extra points if the ball is run or passed into the end zone instead. A field goal, similar to a penalty in rugby, is worth three points. A "safety", worth two points, is awarded if a player is caught in possession in his own end-zone.

In Britain the amateur game is flourishing. There are 28 teams in the British Senior League,as well as an increasing number at university and youth level.

Next week: lacrosse

The British American Football Association (Bfa) (gmblade@aol.com), or the British Senior League (www.gridironuk.com) can advise beginners wishing to take up the sport. For details of the Scottish Claymores, visit www.claymores.com

NFL Europe can be contacted on 020 7225 3070, www.nfleurope.com. For information on the 31 US teams in the NFL, visit www.nfl.com.

For equipment, visit the online shop at www.gridironuk.com or contact PHA Leisure (01908 615 632, www.ta-sports.net), www.footballamerica.com or www.champssports.com.

Shoulder pads, de rigueur in American football, can cost anything from £80-£250 depending on their design. Cheaper versions simply consist of a plastic shell fixed over foam padding, but at the top end of the range, pads employ an ingenious air-management padding system designed to absorb and distribute the shock of a body blow more effectively. Another guard, known as a coccyx pad, is worn at the base of the spine, and further padding is employed to protect the hips, knees and thighs. The whole set, aside from the shoulder pads, will cost approximately £35.

A polycarbonate shell insulated with foam padding and an air-liner combine to make these four times stronger than an average motorcycle helmet; wise in a sport which places such a premium on physical contact at speed. The air pads are inflated from the outside before a game in order to keep the helmet in a fixed position. All headgear should come with a face cage, jaw pads and mouth guard, but the size and shape of these vary according to a player's position. Helmets cost around £135, but most clubs keep spares to loan to beginners, and the same applies to padding.

American football shirts are fabricated from an open-weave mesh to maximise breathability. The knee-length shorts are made from nylon or spandex for stretchability, and should fit tightly over the pads. Shoes, known as cleats, have rubber moulded soles similar to those of hockey boots. A pair can cost anything from £35-£100, and come in a variety of styles to suit players in the various positions.