Swan Lake, Ballet Nacional de Cuba, London Coliseum

In the Cuban National Ballet’s Swan Lake fourth act, the corps of swans do a curious, aggressive attacking run you don’t see in any other production - they lower their heads and charge at Prince Siegfried, with hands fluttering angrily behind them, as if they were the evil magicians, not the creatures under a spell.

Alicia Alonso will be 90 this year, and the miracle-worker who gave birth to Cuba’s amazing incarnation as one of the world's great ballet nations has now turned, thanks to her determination never to retire, into the obstacle to revival. On past tours here, Cuban dancers have managed to cloak that fact with their natural ebullience, but Swan Lake is something else and in last night’s spiritless performance the heftiness of their chains was visible.

For one thing, this production is an overwhelming argument for an authentic Swan Lake choreographic text to be established and set down. Any resemblance to the Petipa/Ivanov Swan Lake is practically coincidental. A few recognisable dance phrases here and there stand out of the wreckage that has been made of most of it, and the lack of purpose and aesthetic context of the choreography provided has left the dancers high and dry. Mime is left in thick hammy chunks, not elucidated, and the whole feels like something that died decades ago and got shoved into a reliquary. One can feel angry about this because this is Swan Lake we're talking about.

I also heavily blame the Cuban conductor, Giovanni Duarte, whose plodding tempi last night would hardly disquiet tortoises, let alone encourage them to dance. Even with the fine orchestra got up by the Coliseum, and the sumptuous violin-playing of Abigail Young in the two great pas de deux of Act 2 and 3, Duarte managed to invert alchemy and turn these golden resources into musical clinker. The one happy surprise was the cygnets, who whipped through in record speed.

Between Duarte’s unmusicality and the bowdlerisation of Odette’s steps into a parade of exaggerated arabesques, even a better ballerina than Anette Delgado would not have stood much chance of creating poetry. I have seen Delgado in the past fare well in Giselle, with gentleness and sincerity, but as Odette/Odile she seemed at a loss interpretatively.  Fast fouettés is one thing (or 32 things) but there is a crying need for lyrical fantasy, for musical imagination, for casting an otherworldly spell. Delgado has the deliciously full Russian arms and upper-body carriage that so many of these Cuban girls have, with an unconscious sweetness in the neck - but it’s less attractively supported by under-turned-out legs and blunt feet. In both sexes there were too muddy entrechats and flat-footed landings (particularly sad in Yonah Acosta, the formerly promising teenaged nephew of Carlos, who as the Jester last night mugged and dashed without finesse across the stage).

The male shortfall - and that’s not something one often had to write about Cuba’s ballet - showed up too in Delgado’s Siegfried, Elier Bourzac, who, in Simon Cowell’s phrase, is not as good as he appears to think he is, doing his few steps with easy athleticism but little stylishness, and undervaluing the drama Tchaikovsky offers musically to his character. Cuba has lost a lot of good young male talents in recent years, flying the coop for other countries. I intensely missed the romantic nobility in this ballet that the great Cuban men have made such tradition of - Carlos Acosta, José Mañuel Carreño and Joel Carreño. The latter’s absence from this tour leaves the Cubans looking bereft of seriousness.

The styling of the production is hampered by ingrained economic realities in Cuba as well as its origins in Alonso’s youth in the 1940s - its spirit in Act 1 is jolly and proletarian, rather than courtly; in Act 3 the national dances are not styled either choreographically or in costume with much coherent sense of de luxe world-travelling. The swan tutus strike the right image, though their undercarriages clearly could do with being remade. The lighting is sickly and outdated, green  for evil doings, white for good ones.

The Cubans created a miracle in ballet. Let them not now take the cynical, deadening route of the reach-me-down Russian pick-up troupes who dully thud so-called “classics” onto the stage in a miasma of increasingly disbelieved hype. Let the Cubans re-find their unique, fabulous dancing soul in their ballet, build on the marvels of what Alonso did for them, and fly ahead with their joyful musical culture and unstoppable love for ballet. There are now many inspiring and careful home-grown hands in which they can place their future. Let it be very very soon.

• Ballet Nacional de Cuba is at the London Coliseum until 11 April, with Swan Lake until Saturday and the gala programme Magia de la Danza from next Tuesday to Sunday. Get tickets on seetickets
  
• The company's tour goes on to The Lowry, Salford 14-17 April and the Birmingham Hippodrome 27 April-1 May. Get tickets on ents24
• Check out what's on at Sadler's Wells this season