LEAH MacRae is flying solo. Over the coming weeks, she will be on a whistle-stop tour around Scotland with her one-woman musical comedy show, My Big Fat Fabulous Diary, tackling subjects from first love and body image to heartache, nostalgia and the calamities of family life.

The Glasgow-based actor, known for her roles in the BBC shows Gary: Tank Commander and River City, is in good form when we speak on a Tuesday lunchtime. With the first performances of the 15-night tour under her belt, any early nerves have dissipated.

According to MacRae, My Big Fat Fabulous Diary is semi-autobiographical ("some of it is based on truth and some of it is completely fabricated – I like that the audience never quite know") and draws on her mantra of positivity, self-belief and not letting the opinions of others define us.

While no stranger to the comedy spotlight – MacRae has starred in the hit play Fifty One Shades of Maggie, sell-out stage shows for Gary: Tank Commander at the SSE Hydro and was a regular on The Karen Dunbar Show – putting her own writing and jokes out there took some convincing.

"When I worked with The Comedy Unit, they were always saying: 'You should write' and I would say: 'But I'm not a writer'. Other people would tell me: 'You should do stand-up' and I'd say: 'But I'm not a stand-up'. For years I pushed against that because I was a bit frightened."

She first performed My Big Fat Fabulous Diary in 2017. Yet, disaster struck in her debut show when MacRae tore her Achilles tendon on stage. "I didn't tear it – I snapped it in half," she interjects, laughing. "It was fully ruptured. It snapped in half on the stage.

"I snapped my Achilles tendon at the end of act one and did act two in a wheelchair. I didn't really feel the pain at first. It was only towards the end of the show that I realised how bad it was."

Talk about the show must go on. "I had to give it a shot," she reflects. "If I had broken a bone, I wouldn't have been that irresponsible. But I knew it was a tendon. I did as much as I could – about 35 or 40 minutes – and then went to hospital.

It has been a long road back to health. "It was horrendous but that makes it all the more poignant for me because the show is about overcoming obstacles," she says. "I have recovered but I am still in pain. It is a big injury. I am still having physio for it and have referred injuries in my knee and back.

"When the orthopaedic surgeon was telling what had happened, he genuinely looked as though he was telling me I was going to die. He was so morbid and sincere that I thought he was joking at first. Now I realise two years down the line why he was so serious. It is a big recovery. I am not a wee, light, sprightly thing and being on crutches is not easy when you are heavy."

Earlier this year, MacRae spoke out after social media trolls made hurtful comments as she recovered from her Achilles injury. "I put on quite a bit of weight because I was immobilised and not able to exercise," she says.

"Anyone who has been injured or immobile will know how frustrating and mentally difficult that is to cope with. To then have people comment on your weight when you can't control it, I just think people need to be a bit more careful with their words."

MacRae says that while she was able to shrug off the cruel remarks, it crossed her mind that not everyone in her situation would be so sanguine. "I have been a size 16 to 18 for a lot of my adult life but I am very fit and strong and healthy," she says. "It never really bothered me at all.

"I didn't feel bad about my weight. But some people do feel bad and I felt I should say something for them because if you feel bad about yourself, the last thing you need is someone else making it worse and so publicly too."

The eldest of two daughters, MacRae was born in Belfast where her father was in the army. The family then moved to Longstanton near Cambridge. They arrived in her parents' native Glasgow when MacRae was in primary five at school.

"It was a huge change in my life," she recalls. "I had this polite accent and had come from a little school with a duck pond, outdoor pool and rugby fields in a small village and then we moved to sunny Govanhill. That's where we landed at first before moving to King's Park."

She comes from a tight-knit family. "My number one girl is my gran," says MacRae. "We call her Fairy. She is 86 and the best wee woman. My gran is inspirational to me."

What was MacRae like growing up? "That transition from coming out of the army [life] and into school in Govanhill was really difficult. It was a huge shock. It felt like two different cultures. I had to learn very quickly how to become tough and how be a kid in Glasgow."

Even so, she describes herself as a chatty child with a flair for the dramatic. "I had a five-year diary with a padlock on it," says MacRae. "Inside, it said: 'If you are reading this diary then you must have found the key that I never take off from the chain around my neck. Keep reading but you must never divulge this to anyone.'" She cracks up laughing. "I was clearly always going to be an actress."

MacRae studied acting at Langside College in Glasgow. She began doing sketch comedy and sitcoms in her late teens and early twenties. One of her earliest roles to prick the public consciousness was as ditzy but loveable Julie Jackson in Gary: Tank Commander.

The role was written specifically for her by the show's creator Greg McHugh, whom MacRae had first watched perform as the camp, perma-tanned and cheesy pasta-obsessed squaddie Gary McLintoch at the Edinburgh Festival Fringe in 2007.

McHugh's satirical take on frontline life was developed into Gary's War, a one-off pilot for More4 that won a Scottish Bafta in 2008. A BBC Two Scotland series followed a year later. "Julie Jackson is my favourite part I have ever played," says MacRae. "She was written for me by Greg and I was on board from the very start in development and the first rough cuts.

"The cheesy pasta monologue that everyone loves, I know that inside out. When we were at the Hydro [in 2016] and Greg put it in the show, I was greetin' because I was so proud of him. I remember watching him at the Gilded Balloon in front of 50 people doing that monologue."

She would love to reprise the role if the opportunity arose. "The part of Julie is a total joy to play. Greg is busy and all the rest of the cast are busy which is lovely. I'll need to buy that boy some chips and cheese so we can get a chat about it."

More recently MacRae, who lives in south side of Glasgow with her husband Paul, has played fun-loving and free-spirited Ellie McLean in River City for the past five years.

"When I joined people asked if I would get bored playing the same character," she says. "But you don't get bored. Playing the same character is a joy and it is so different to other types of jobs where you are taking on different characters all the time.

"In a continuing drama, you know your character inside out and get thrown into all these different situations. You can't wait to see what is coming next."

Next for MacRae is hitting the road. One of the most daunting things about a Scotland-wide tour, she says, is whether her brand of humour is universal. She started the tour in St Andrews earlier this month and then headed to Livingston, Kirkcaldy and Largs for the opening dates.

"In Scotland, you travel 10 minutes down the road and people use different words," says MacRae. "Across the country, for people to be laughing at the same bits, it means I am doing something right and it makes me feel really happy with the work I have done."

My Big Fat Fabulous Diary is at the Beacon Arts Centre in Greenock on Thursday, Easterbrook Hall in Dumfries on Friday and the Theatre Royal in Glasgow on Sunday. There are eight further dates across Scotland finishing at Eden Court Theatre in Inverness on June 9. Visit leahmacrae.com

LEAH MACRAE: LIFE AND LOVES

Career high: Standing on stage in front of a full house at the Edinburgh Playhouse doing a one-woman show. That was incredible.

Career low: Snapping my Achilles tendon on stage. I thought my career was over in that moment.

Favourite film: Beaches. I also love gangster films such as Once Upon a Time in America, Scarface and Goodfellas.

Last book read: Wrong Place Wrong Time by David Perlmutter.

Best trait: Kindness.

Worst trait: Worrying.

Best advice received: Worrying is a misuse of imagination. The other one is I love – as cheesy as it sounds – is follow your dreams. That is my motto.

Biggest influence: Julie Walters, Bette Midler and Billy Connolly.

Favourite meal: Spicy chicken curry.

Favourite holiday destination: Thailand.

Favourite music: I have diverse musical tastes. My favourites to listen to on the beach in Thailand were Porcelain by Moby and Voices by Dario G. I love a bit of Enya too – I am quite cheesy.

Ideal dinner guests: Everyone I love who isn't here anymore. Elvis Presley, Julie Walters, Bette Midler, Al Pacino, Robert de Niro, Martin Scorsese, Kate Winslet, Kelly Osbourne, Pink and my gran.