• President’s collapse while jogging raises health fears
• Aides dismiss ‘premature’ reports of heart problem

Nicolas Sarkozy, the French president and fitness fanatic, was taken to hospital today after he collapsed while jogging through the park of the Palace of Versailles.

The president was taken by helicopter to a military hospital in Paris at the end of his Sunday run in the grounds of La Lanterne, his weekend retreat near Louis XIV’s palace. The president, said to be on a punishing new diet and exercise regime, had gone for a midday run in high temperatures, and collapsed at around 1.30pm.

The Elysée Palace sought to play down the health scare, saying the president would be back at work , but it came as a knock to Sarkozy’s image as the youthful jogging obsessive dubbed “Speedy Sarko”.

An unnamed witness told Agence France-Presse she saw a jogger surrounded by bodyguards stumble and collapse and that soon after, Sarkozy’s wife, Carla Bruni-Sarkozy, arrived at the scene on a scooter. The president was taken to Val-de-Grâce hospital in Paris with his wife, who was at his bedside as tests continued.

The Versailles hunting lodge where the couple were spending the weekend was also where they celebrated following their marriage last year.

Five hours after the president was admitted to hospital, his chief of staff, Claude Guéant, said he was doing well and “talking normally to hospital staff”. The exact nature of the health scare was not spelled out, but the president’s entourage suggested it was a minor episode linked to the vagus nerve, perhaps involving a drop in blood pressure and lowered heart rate. The Elysée said the tests he was undergoing in hospital were “standard”.

“He had this problem when he was exercising, jogging. He has come round,” Guéant told Le Parisien website. “The president is totally conscious, his episode did not last very long.” Asked if Sarkozy had suffered from a heart problem, Guéant said: “That is without doubt wrong. It is premature to say.”

Patrick Balkany, a centre-right mayor and longtime friend of the first couple, said: “He’s doing well, he’s hungry, he’s complaining, everything’s fine.” He blamed the “minor” incident on fatigue, the president’s overexertion and the strain of his strict new weight-loss regime. He said the president needed to exert himself less and “eat a bit more”, adding that he had recently been honing his regime to such an extent “that he looked more like a Tour de France racer than a president. I hope this will be a warning to him to moderate his efforts a little.”

Gordon Brown last night sent a private message to Sarkozy, expressing his support and wishing him a speedy recovery.

To suffer a health scare while exercising is significant for Sarkozy, 54, who has deliberately built up his image as an energetic and active young president by inviting TV crews to film him sweating on his gruelling morning runs.

Where other presidents preferred gentler pursuits – François Mitterrand would stroll and Jacques Chirac watched sumo wrestling – Sarkozy has stepped up his regular 45-minute jogs.

The sight of him pounding the pavement in a sweat-drenched NYPD T-shirt and matching Nike shorts, socks and trainers is so commonplace that satirists have called him “Nike-olas”.

Recently he has been taking regular runs with his wife, a former supermodel, and work-outs with her personal trainer. He and Bruni were seen jogging in New York earlier this month. Last week Sarkozy visited the hardest stage of the Tour de France, talking of his love of cycling.

The incident reopened questions of transparency over French presidents’ health problems, which have been shrouded in secrecy in the past. Mitterrand’s cancer was kept private for years.

When he was elected, Sarkozy vowed to be transparent about his health, with regular bulletins. However the Elysée kept quiet when Sarkozy was in hospital to have a throat abscess removed in 2007 after his divorce from his second wife, Cecilia. That hospital stay was only revealed months later by two journalists. One said the president had gone to such lengths to hide his illness that he had carried on with a state visit to Morocco, during which the foreign minister, Bernard Kouchner, a doctor, treated him.

Sarkozy’s latest medical report was released on 3 July, saying his cardiovascular and blood test results were “normal”. But the president is known in political circles to have long suffered from migraines. Teetotal, but partial to indulging in chocolate and desserts, he has recently lost weight. On a visit to Windsor castle last year, a miniature bottle of olive oil was placed beside his plate before dinner.

The Elysée said Sarkozy expected to be released from hospital on Monday morning and would still travel to Mont Saint-Michel in Normandy on Tuesday to give a scheduled speech on protecting French heritage.

He is due to chair his last cabinet meeting of the summer on Wednesday, and is then expected to spend three weeks on holiday at his wife’s vast family retreat in the south.