Personal trainer Yusef Bouattoura is a Muslim former gang member with a criminal record.

But his life is now on the up, thanks to his thriving business and his loyal Jewish clientèle, without whom, he believes, he would still be in prison.

Yusef, 22, grew up in Stamford Hill, north London. By the time he was 15, he had already  been stabbed twice and jailed for two and a half years — though he is reluctant to go into detail about his crimes.

Today, he lives in Mill Hill, north west London, and runs a successful personal training business. And he is full of praise for the clientèle who have helped him build it up. 

“Nearly all my clients are Jewish,” he said. “They have helped me in so many ways, from advice with setting up my business, to not judging me and my past because I’m very honest with people from the start.”

His large house, which doubles as his fitness studio and has its own swimming pool and spa bath, is not where you’d imagine a young ex-offender to be living. 

Downstairs boasts an office, gym and open plan kitchen/dining room that would not be out of place on an episode of MTV’s Cribs, which peeks into celebrities’ enormous houses.

But it is immediately obvious that Yusef, whose family is Italian and Algerian, is not your average 22-year-old. 

He rents the property from a client who has taken a leap of faith on the former gang member.

“I was looking for somewhere to rent for ages but kept getting rejections,” he said.

His house might look like a glamorous family home, but he is still a young man whose peers are renting box rooms in university towns and learning to cook for themselves. 

Yusef, whose clients include some of the community’s most well-known figures, says he has raised more than £20,000 for Jewish charities such as Norwood, One Family, Gift and Rays of Sunshine by holding fitness sessions and getting attendees to donate to charity.

But before he left prison, he knew little about the Jewish community.

“Where I grew up in Stamford Hill all I knew about was Orthodox Jews. They were our neighbours, our landlords. We had a nice relationship with them but they kept themselves to themselves and I thought that they were the only Jews out there.”

After being released from prison, he qualified as a personal trainer.

“At the time I went to prison I was obese and depressed but the PT course allowed me to get into shape,” he says. 

Yusef started applying for jobs in gyms but his criminal record meant he faced a lot of rejections. 

“I didn’t give up,” he tells me, and eventually he was given a job by Pure Gym in Finchley. 

“I was the youngest there, with the least experience, so I had to find a way to boost my confidence. I struggled to get clients at first so to get my name out there I started offering free classes. I wasn’t earning enough money to live because I was doing sessions for free. I was homeless and living in the gym’s toilets and not telling anyone.”

In time, he built up a steady client list and was soon earning enough money from private clients to leave the gym and work for himself. 

But Yusef had no idea they were nearly all Jewish. 

He jokes: “I started noticing the Star of David that they were wearing. I just thought maybe they have all been on holiday together and it was a souvenir thing. 

“Then people would tell me they can’t work out on Friday or Saturday. I had so many clients called Cohen, I kept asking if they were all cousins and they laughed at me and said, ‘No we are Jewish’.”

He and his brother, Idris, who recently left school and also works as a trainer, have just returned from Israel where they ran free fitness classes on the beach. 

“We were invited by a client,” he says. “Everyone I spoke to said ‘you are going to get questioned’,  be prepared for it.” 

But nothing could have prepared them for the bedside manner of Israeli security.

Idris, 18, says: “We got stopped for three hours and questioned three times and, just when we were about to be let in, these guys pop up from nowhere and pulled us to the side and questioned us again.

“I thought it was a joke or that it was fake. I thought we were going to get kidnapped.” 

But they did not let it ruin their experience. “I understand it,” says Yusef. “They have high security and I could see they were doing it to other people as well.”

In Israel, the brothers were “amazed by all the different people living side by side. 

“You have Muslims, Jews, Christians — everyone together and they were all friendly. 

“It is not like they show you on the media. 

“Of course, it can be more complicated but we saw people together. 

“In Jaffa there were Jewish and Muslim children playing and it was quite wonderful.”

Yusef says he has enjoyed getting to know more about the community, but thinks “there are too many festivals during the year”. Idris agrees: “We have one or two where you eat lots. Jews do it every Friday night, it’s too much.”

Learning about the community has taught Yusef “a lot about family, the importance of being together and solidarity.

“It has taught me a lot about charity. The Jewish community is the most giving group I have met which is why I have always wanted to give back to them.”