I was Princess Diana’s personal trainer and I’ve kept her secrets for decades. Here’s what she told me after her marriage ended…

Late August 1997 and Princess Diana, post workout, was ready to ‘do diaries’. She was flying out to St Tropez for a holiday in a few days and wanted to book a few sessions with her personal trainer for when she got back.

She marked out some dates on a card for the start of September, and handed it to Jenni Rivett, who made a note, and wished her a good trip.

Jenni, Diana’s trainer and confidante for the previous six years, knew who she was joining on this holiday – Dodi Al-Fayed. But how much did she know about their potential romance?

Was Diana happy? Was she in love? Was she excited about her holiday?

Jenni, a spry and lean South African, now 65, pauses and thinks carefully. Nearly 28 years may have passed since the death of her most famous client, yet the discretion and loyalty that served her so well, that so few had afforded the Princess in her short life, is firmly embedded.

‘She was excited to get away, she needed a break, and she loved being in the sun, but there was a lot of stuff going on with her,’ Jenni says cryptically. ‘A lot of sadness, too. While she was always terrific fun, had a great sense of humour, I always got this sense of underlying sadness about her.

‘She didn’t want this life. She didn’t want any of it. All she ever wanted was to be a good wife and mother.’

She does know that Diana would have been further saddened by the divided lives of William and Harry.

Jenni Rivett was Princess Diana’s trainer and confidante for the six years leading up to her death

‘All [Diana] ever wanted was to be a good wife and mother,’ Jenni says

‘Diana loved her boys; they were everything to her. She would have been devastated at what is going on between them today,’ she says.

Of course, for reasons everyone knows, Diana would never make it to those appointments. She was fatally injured in the early hours of August 31, alongside Dodi who was killed instantly, in a speeding car driven by a drunk chauffeur – who was also killed – as he tried to outrun pursuing paparazzi.

Jenni was in Turkey at the time: she had taken advantage of the break in her schedule to take a holiday with her husband and Kirsti, their daughter, then four.

Naturally the news – delivered by a friend in the early hours of the morning – left her reeling. Not just at the loss of a client – probably the most prized in the business – but by the personal loss, too. She was, after all, at Diana’s side for an hour three times a week, honing and sculpting the most photographed body in the world.

‘It’s been nearly 30 years, so I feel I can talk about our time together now, but only the happy memories, the fun things,’ she says.

Jenni started working with Diana in 1991 after getting a phone call out of the blue from Paul Burrell, Diana’s butler and right-hand man, that ‘had me shaking in my trainers’.

That period, 1991 to 1997, often called ‘the war of the Windsors’ was a nadir for the Royal Family. For Diana, it encompassed some of the most difficult years of her life as her marriage disintegrated, leading to her official separation from Prince Charles in 1992 and their divorce four years later, in August 1996.

It also saw Diana’s rebirth as a strong and independent woman, with Jenni helping the princess navigate this period with her absolute loyalty guaranteed. ‘Of course, as a personal trainer you can become very close to someone.

A young Jenni with her client and friend Diana 

Following her divorce from the then Prince of Wales in 1996, Diana was reborn as a strong and independent woman

‘Sometimes Diana would tell me things so personal I would ask her: “Please don’t say any more because if it ends up in the papers tomorrow, you will think it was me.”

‘I would give her the very best advice I could, yet I’d pinch myself – here I am, consultant to the Royal Family! But saying that, I knew my place. I never brought up subjects myself, I never overstepped the line, and I think she appreciated that.’

It’s hard to imagine the forever-young and beautiful Diana, who would have turned 64 next month (and be a grandmother of five), maybe struggling with aches, pains and a burgeoning waistline, like the rest of us. Or maybe she wouldn’t – not if she’d kept Jenni on board.

At 65, Jenni can easily pass for a woman in her 40s, which she puts down to working out three times a week and thinking ‘intuitively’ about her diet and lifestyle.

At 5ft 5ins and a trim size 8, she says she’s fitter and healthier than she ever was in her 30s.

Jenni came to London in the late Eighties and her first job was at the exclusive studio Body, in Chelsea, before she moved to the Harbour Club, where Diana was a member.

‘Being a naive South African, I never realised how many famous faces were coming and going. I became the studio co-ordinator and trained many without realising who they were.’

Past clients include Shakira Caine (Michael’s wife), Elizabeth Hurley, Jeffrey Archer, Bonnie Langford and TV presenter Anneka Rice.

‘People liked me because I was very diligent and didn’t mind approaching people and correcting them. People started asking me in the gym if I did personal training, and the private work grew from there.’

Diana later told Jenni she’d heard about her from three different people at dinner parties. ‘I was very nervous [when I first met her]. No one explained the protocol to me.

‘For four years I didn’t know I had to curtsey, until I saw someone else doing it. I was shocked and apologised, but Diana said: ‘Oh Jenni, you are from South Africa, I know you didn’t know. Please don’t ever curtsey to me.’

‘On that first visit, she bounded into the room and said: “Now, what can you do with this body?” She was in good shape, but her posture wasn’t great. The legs were fab, and they got even better. We also worked on her abs and her core.

‘She was so dedicated to her training – with Diana it was all about the technique, she liked to get things right. She’d spot people in the Harbour Club [in Chelsea] not doing exercises correctly and tell me to go over and tell them off. I’d say “No, you do it!” ’ (which she didn’t, of course).

‘She loved doing ‘Step’ classes which were big in the Nineties, so we would do that on the days we trained at Kensington Palace and then follow up with weights and stretches.’

Diana had studied ballet as a child, and dreamed of becoming a professional dancer, before growing too tall (5ft 10ins), but her love for ballet was apparent, says Jenni.

‘She was always keen on doing ballet stretches at the barre at the Harbour Club. When we trained at the gym, she liked to do cardio on the elliptical machine – and then we would do strength training with free weights and stretching at the end.

‘On some days Diana would want to go out into the gardens of Kensington Palace and power walk and then do our exercises when we got back. She also asked me to teach her to rollerblade, and we sometimes did that as an extra fun activity together.’

For this, Jenni says, they would go out in public in Kensington Gardens, with Diana in her baseball cap ‘for disguise’.

Not that it always worked. In 1995, paparazzi photos of Diana proficiently zooming around the park ran in the News of the World under the headline ‘Princess of Wheels’.

Another role Jenni performed was to act as look-out when Diana left the gym, trying – and usually failing – to avoid the ever-present photographers outside. It was Diana who came up with the idea of wearing the same sweatshirt every day – a blue Virgin Atlantic one, given to her by Richard Branson – so there wouldn’t be any new images to sell.

Years later, Jenni was gifted this sweatshirt by Diana’s family. In 2019, it was included in an auction of Diana memorabilia and sold for more than £40,000, which Jenni donated to a good cause. You feel Diana would have approved.

‘It was just sitting in a cupboard and there was always the fear of it being stolen or gathering dust,’ says Jenni. ‘I wanted to help my Malawian gardener put his son through school, and the proceeds from the shirt allowed me to do that.’

It was during her time as Diana’s personal trainer that Jenni became pregnant with Kirsti, who is now nearly 32. ‘Diana was so happy for me. Just before Kirsti arrived (in 1993) she gave me a beautiful little cardigan and a card saying “Something small for your bundle should it arrive whilst I am away, Love Diana”.

‘On occasions I would be called up to Kensington Palace at the last minute, and once or twice I took Kirsti with me. I remember William and Harry fighting over who was going to hold her. The boys would often muscle in on Diana’s workout sessions too, and she’d scold them and order them out of the studio if they didn’t behave.’

Back then, she remembers, Harry was always ‘the naughty one’, but both had impeccable manners – even when winding up their mother. Diana accompanied Jenni on a skiing trip to Vail, in Colorado, in December 1994, prior to her first Christmas without her boys. It was to help her escape the stress while the boys were at Sandringham with Charles and the rest of the Royal Family.

About a year after Diana’s death, Jenni’s own marriage broke up – although she and her ex-husband, Howard, remain very good friends.

Today Jenni divides her time between Franschhoek on the Western Cape in South Africa, and the Cotswolds, where she spends three months a year.

Jenni is still a much-sought after personal trainer, working with hundreds of clients all over the world via her three-times weekly Zoom classes.

She also has a new online fitness programme, Train Like A Woman, offering nutritional and fitness advice to women in their mid-life and beyond – particularly to women in their 60s, for whom fitness and muscle building are key. ‘There seems to be a lot of focus on women in their 40s, and more recently working through the menopause, but it’s women in their sixties that seem to be overlooked,’ she says.

‘Once you hit the age of 65, if you fall and break your hip or your femur, there is a 15-30 per cent chance you will die within a year. And of the 70-80 per cent of people who don’t die, 50 per cent will experience a significant loss of function that never recovers.’

Joint mobility, she says, can be achieved with just three minutes of exercise a day, literally ‘pumping’ synovial fluid (the lubricant inside joints, which works much like engine oil, allowing the different parts to move freely without friction).

‘Exercise is all about quality. Do it properly, three times a week, and walk in between.’

She’s also a keen proponent of ‘not being too hard on yourself’.

‘I’m a big believer in hitting the delete button,’ Jenni says. ‘If you can’t resist that cake or chocolate, have it… then move on. Do your work out and forget about it. Don’t think it’s all over.’ Whenever she’s in the UK, Jenni always makes a special pilgrimage to Kensington Palace and stands outside its famous gates. ‘The one thing that saddens me is that Diana never knew how much she was loved,’ Jenni says.

‘She’d read something negative in the press, and ask, “Do you think people really believe all this about me?” I’d reassure her that people absolutely knew the truth.

‘The day after Diana died, I went to Kensington Palace and saw the sea of flowers outside the gates.

‘I put my flowers down and I said to her: “Do you believe me now; how much people loved you?’

Jenni’s QuickTone8 workout routine

This 11-minute routine, is one of the most profound I’ve ever learned. I believe working out in the anaerobic zone (any activity lasting from 30 seconds to two minutes and with your heart beating between 137-154 bpm) promotes the release of human growth hormone (HGH) – credited with increasing libido, lowering anxiety and going after fat reserves like a heat seeking missile!

1. Start with a 3-5-minute warm- up, gently jogging on the spot.

2. Now sprint on the spot for 30 seconds, then rest for 60.

3. Repeat eight times.

4. You should be working hard enough that you are out of breath and talking is not easy.

5. After working out do not eat any sugar, fruit or carbs for two hours, as this will obliterate the action of the HGH released into your bloodstream.

Follow Jenni on Instagram at: www.instagram.com/jennirivett_fitness

For Train Like A Woman, visit jennirivett.com