The striker, who started working with Verheijen at Manchester City, pays the Dutchman out of his own wages.
"He can play for another three or four years," Verheijen told BBC Sport.
Last month Bellamy said he had arrived at the Cardiff City Stadium from Manchester City "a wreck", adding: "I was very close to surgery."
The 39-year-old Verheijen believes that "explosive" players like Bellamy, with fast-twitch muscle fibres, should follow an individual, specialised programme - part of the periodisation approach to smarter training - to keep them fresh and prevent overtraining.
Bellamy has a history of serious knee injuries and has undergone knee reconstruction and career-saving surgery from renowned American knee specialist Dr Richard Steadman.
Prior to working with Verheijen, the 31-year-old Bellamy had never managed to play 15 consecutive games in 12 seasons as a professional, but during the 2009/2010 campaign, the Welshman played 42 games both for City and Wales.
"The medical staff at Cardiff are doing a great job," said Verheijen, who spoke to BBC Sport following a presentation at the UKSEM sports medicine conference at the end of last month.
"If you look at his knee in August. he can play every week now and he can train. If he plays one game a week and we keep applying his approach he can continue playing."
In September Cardiff manager David Jones said Bellamy had "overdone" pre-season training at City.
"He wanted to impress the manager Roberto Mancini in pre-season and that is understandable. We've just paid that penalty," said Jones.
Verheijen added: "Freshness is the crucial factor in football. Explosive players need more recovery time.
"Usain Bolt will do a sprint and then he rests for 10 minutes. Everybody judges that he is lazy, but he has so many fast twitch fibres he needs that rest - you need more recovery time.
"That is why Arjen Robben had the best season at Bayern during the last campaign. We spoke with the people at Munich and they reduced the volume of training."
What's your view on periodisation? In October, Bellamy was effusive in his praise for Verheijen's approach, telling the Feyenoord Fan magazine last month: "Thanks to Raymond, I only train 50% of what I used to train in the past, but now I train at 120mph.
"As a result, I have never felt better before. Last season, in the Premier League, I was in the top three players with the highest work-rate.
"That's why I have asked Raymond to join me at whatever club I would go. He's with me at Cardiff two days per week to develop my individual periodisation.
"I pay for his services myself which proves that for me being top fit is more important than money."
On Tuesday read the BBC Sport website's analysis of "periodisation" training to discover out if top players are suffering injury due to overtraining.