Socialist MSP Tommy Sheridan has told a court that his only weaknesses were the word game Scrabble and sunbeds.
Tommy Sheridan has begun calling his witnesses
Mr Sheridan has brought an action against the News of the World after claims that he indulged in champagne, cocaine and swingers' sex clubs.
The former SSP leader, who has been conducting his own case, said his busy lifestyle meant he had no time for a "secret life of sexual Olympics".
The 42-year-old denied that he drank alcohol or snorted cocaine.
As proceedings entered their third week at the Court of Session in Edinburgh, married father Mr Sheridan said he would be calling evidence to counter all of the allegations made about his behaviour.
Mr Sheridan denied that he had an affair with former prostitute Fiona McGuire, who was named as an alleged lover earlier in the hearing.
Prior to calling his witnesses, Mr Sheridan told the court: "I am hardly likely to have time for any secret life of sexual Olympics.
"You will hear of my addiction to Scrabble and sunbeds, not champagne, cocaine and swingers' clubs.
"The evidence I will lead will establish the truth about me as an individual and a Socialist."
Mr Sheridan said he would prove that allegations of group sex involving three-in-a-bed and five-in-a-bed - as well as claims about a trip to a Manchester swingers' club and an orgy in a Glasgow hotel - were untrue.
Rosemary Byrne was called by colleague Tommy Sheridan
Rounding on the newspaper, he said his defence would be clear.
Mr Sheridan said: "It will establish that the liars and the hypocrites are within the News of the World beast and that I did not have an affair with Fiona McGuire or anyone else during my marriage.
"I have never attended a swingers' club. I have never had sex with a prostitute or attended a sex party in a hotel."
Referring to an article, published in November 2004, which said he had a four-year affair with Ms McGuire, Mr Sheridan said: "That lie has been at the core of the case since day one but despite three weeks of evidence I hope that my case to you will prove that it has not been substantiated one iota."
Giving evidence, fellow Scottish Socialist Party MSP Rosemary Byrne said she had never heard Mr Sheridan admit going to a swingers' club.
She also said she had no recollection of minutes being ratified for a party meeting in 2004.
Allegations about Mr Sheridan's sex life were said to have been discussed at the meeting after a series of articles in the News of the World.