At college, I used to go to the gym regularly but I never liked the music they played in the classes. I trained as an instructor largely so that I could have control of the stereo. Now I teach twenty hours of aerobic classes a week and so I always associate physical activity with banging house music at 140 beats per minute.

This is not as crazy as you might think. Music and exercise have long been known to be close companions. (9) __________________________ . He is also the architect of the Brunei Music Rating Inventory (BMRI), designed to rate the motivational qualities of music.

Karageorghis says we have an underlying predisposition to react to musical stimuli. 'Music is beneficial,' he explains, 'because of the similarities between rhythm and human movement. The synchronisation of music with exercise consistently demonstrates increased levels of work output among exercise participants. (10) ___________________ .

For James Cracknell, the rower, the ideal music was a Red Hot Chili Peppers' album, which he says played an integral part in his preparation and, ultimately, his Olympic victory. (11) ___________________ . If you are not familiar with this word, it means that during repetitive exercise, music essentially diverts attention away from the sensation of fatigue. The right music can almost persuade your body that you are in fact having a nice sit down and a coffee.

Not everyone, however, shares the same taste in tunes. 'Can you turn that racket down?' said a participant in one of my classes before storming out. Reaching a consensus on music is notoriously tricky - which makes communal exercise classes problematic. There are, however, some rules that professional fitness instructors follow. (12) ________________ .

Most importantly, however, the music should mirror your heartbeat. The instructor should choose the music to go with the different phases of a class, from the warm up, to high intensity, to the final relaxing phase. It's advisable to follow this sequence when you work out alone, too, and not make the mistake a good friend of mine made. (13) _________________ .

Instructors and gyms often buy ready-mixed CDs that come with a music licence, without which they can be fined heavily. A frequent complaint by those who go to classes is that they hear the same old songs over and over again. (14) _______________ . It is also true, sadly, that most people respond best in motivational terms to quite awful songs - music they wouldn't necessarily be proud to have on their iPod.

(15) _____________ . In order to prepare mentally, for example, golfers can get hold of a special range of music just for them. Whatever your sport, I'd like to give you some final words of advice. As Karageorghis suggests, enjoy the beat and let the music motivate you, but never forget your main objective is to exercise and music is only there to help you do that.

A But perhaps the most useful thing about music is that it allows even the humble gym-goer or runner to practise a technique used by elite athletes, known as 'disassociation'.

B These days you can find music tailored to suit an incredibly diverse range of sports and exercise needs.

C One of them is that the music must be appropriate to the type of class and not just the instructor's personal enthusiasm for a particular genre or artist.

D This is mostly because only a limited number of them are released for public performance each year, and partly because teachers universally favour the most popular tracks.

E The most convenient is the gym called Third Space in London's Soho, which does several sessions a week to live DJ accompaniment.

F He was cooling down to techno music, which left him feeling nervous and twitchy all day.

G Choose the right music and, according to Karageorghis, you can up your workout productivity by as much as twenty percent.

H Dr Costas Karageorghis, a sports and exercise psychologist who is also a musician, has spent more than a decade studying the link between athletic activity and music.