A company director who did a day's work and then spent the night cycling 120 kilometres, crashed his car as he drove the next morning and killed another driver.

At the time of the crash, Nicolas Day had gone 27 hours without sleep following his taking part in a midnight cycle ride event from Hyde Park to Whitstable in Kent.

But as he drove home to his family in St Albans, his BMW X5 veered into the oncoming lane and struck a Nissan Micra driven by 47-year-old father of two Andrew Viner.

The devoted family man died at the scene.

Day told police officers moments before the collision he had suffered a cramp in his leg.

On Friday at St Albans Crown Court, Day, 30, a married father of a young daughter pleaded guilty to causing the death of Mr Viner on June 18 by careless driving.

The collision happened on the B651 Wheathampstead Road in Sandridge near St Albans.

Sally Mealing-McLeod, prosecuting, said it was around 10am and the court heard Mr Day was returning home having finished his 120-kilometre bike ride in Whitstable where his car had been left.

The prosecutor said the weather was fine and visibility was good as Mr Day's vehicle entered a gradual bend.

He was driving within the speed limit but the car crossed the central markings and smashed into Mr Viner's car, which was coming in the opposite direction.

The father of two, who lived in Wheathampstead, died at the scene.

Police accident investigators found evidence that he had tried to brake and steer his car towards the kerb in an attempt to avoid the collision.

Day, of Seamen Close, Park Street, told police he was a fit and athletic man and denied falling asleep.

But he said he had suffered a cramp in his right leg just before the crash.

On Friday his barrister, Kerry Waitt, said it was clear Day had failed to negotiate the bend in the road.

He said that having suffered the cramp, Day's lack of sleep may have had an impact on his reactions and his driving fell below the standard expected of a reasonable driver.

Mr Waitt said it was a combination of the cramp and impaired reactions which had caused the defendant's car to veer into the oncoming lane with tragic consequences.

Passing sentence, Judge Stephen Warner told Day: "The accident happened because you failed to negotiate the bend and you crossed over onto the other side of the road.'

As a result said the judge, it had meant Mr Viner had "no real chance of avoiding the collision".

The judge said there was no evidence that Day had fallen asleep behind the wheel but he told him he should have been able to deal with the onset of a cramp in his leg.

He went on: "It's accepted that lack of sleep contributed to your inability to react safely."

The judge said that although there was evidence that Day was "an extremely fit man" who was able to deal with little sleep and function effectively, he was satisfied lack of sleep that morning had been a contributing factor which cause the BMW to cross the centre line.

He told Day he would have to live with the knowledge that his driving that morning had resulted in the death of a family man and devastated his family.

The judge sentenced Day to seven months imprisonment suspended for two years.

He was told he must carry out 200 hours of unpaid work and he was banned from driving for 18 months and his licence endorsed.