CARRYING tyres and heavy barrels of water while running for miles, Irene Malvezi is a long way from the woman who was first diagnosed with chronic fatigue syndrome 18 months ago.
When the graphic designer from Pilgrims Hatch was first struck down with the incurable disease, all she could think about when she finished work was how soon she could get into bed.
Yet now, thanks to the women who run Brentwood Boot Camp, Mrs Malvezi feels stronger and happier, even adopting the mindset that she no longer has the illness, which is also known as ME.
The 43-year-old, of Danes Way, said: "Boot camp has improved my life a lot.
"When I first went there I was really nervous because I thought I was going to kill myself, but it wasn't like that.
"I feel stronger, I don't feel pain in my body any more and I miss it when I don't go there.
"I do feel tired every now and then but it is nothing like what I had before."
Mrs Malvezi, who lives with her husband Chris Simms, 44, continued: "People who have known me for a long time and who have seen me weak all the time ask me how I do it.
"They can't quite believe it is the same person.
"I don't like to say I have chronic fatigue syndrome any more and I don't want to say it ever again."
Originally from Sao Paulo in Brazil, Mrs Malvezi was first diagnosed with moderate ME while living in Epsom, Surrey.
Recalling how desperately tired it made her feel, she said: "I kept getting up in the morning feeling totally drained, being drained the whole day and going to bed totally drained.
"I was able to work because I was forcing myself, but I couldn't drive.
"I also found socialising difficult – I needed to be in bed."
Although ME cannot be cured, it can be managed and so she cut her hours at work and ditched fruit, chocolate and alcohol from her diet in a bid to feel normal again.
Boot camp, which takes place at Ashwells Sports and Country Club and Larkins Playing Field, both in Pilgrims Hatch, would appear to be the final piece in that puzzle.
Mrs Malvezi, who first attended boot camp in May, said: "At the beginning I had to run around the tennis court at Ashwells three times, although I couldn't even do half a circuit. But now I can go around the court five times if I want to.
"Every time you go there you do something different but you mainly run a lot, sometimes carrying a tyre or a barrel of water, and also do lots of one minute exercises like squats."
Besides improving her physical stamina, Mrs Malvezi has reaped other benefits from her thrice weekly boot camp sessions. "I have lost half a stone in weight and I feel so good about my body now," she said.
"I'm also not as rigid with my diet as I was.
"I have some fruit and some chocolate now and again but I don't really touch alcohol and will only have a sip if Chris has a beer or a glass of wine.
"Before, if I had chocolate I would start itching within 20 minutes, but now I am fine."
Mrs Malvezi said she hopes her experience will help other people with ME to come to terms with the illness and go on to lead a normal life.
"I am as happy as I can be," she added. "ME, for me, is over – I am normal, I have nothing wrong with me and I am a healthy person now."
For more information about Brentwood Boot Camp, call 07808 169238, 07774 671647, or visit www.brentwoodbootcamp.co.uk