I'm learning to swim for an Ironman triathlon in memory of my wife

A man whose wife died six months after being diagnosed with a brain tumour is entering a gruelling triathlon - even though he is still learning to swim.

Alan Johnstone is aiming to compete in the Austrian Ironman competition, which involves a 2.4-mile (3.8km) open-water swim, a 112-mile (180km) bike ride and a 26.2-mile (42km) run.

The 41-year-old is raising money for charity in memory of his childhood sweetheart, Anneka, who was 33 when she died in 2019.

Since then Alan, from Dumfries, has raised more than £100,000 but the former RAF engineer admits his latest challenge will be his toughest yet.

Their daughter, Sienna, was 13 months old when her mother died from an aggressive glioblastoma.

The former NHS dietitian had been fit and healthy but within a month of her diagnosis, she was unable to walk.

''It started with some balance issues and at first the doctors thought it might have been herpes simplex virus (HSV)," Alan said.

"She was given antibiotics but there was no improvement after 24 hours.

''She was taken for an MRI scan and we were warned it would either show inflammation of the brain or a brain tumour."

Alan said they then received "the worst news you could ever expect".

"It went from feeling dizzy to being in a wheelchair in a month," he added.

"It was absolutely devastating.''

Anneka died in November 2019, six months after her initial diagnosis.

Brain tumours are the biggest cancer killer of children and young adults under the age of 40 in Scotland, with about 1,000 people diagnosed with a brain or central nervous system (CNS) tumour each year.

Since her death, Alan has completed the London and Boston marathons to raise money for research into the disease that ''tore his family apart''.

''Anneka was an amazing person, kind, caring, smiley," he said.

"Her strength was unbelievable and she was more worried about us than herself."

The NHS clinical engineer said that he had never had a swimming lesson and this would be his most daunting challenge to date.

The Ironman races are renowned for their unrelenting pace, as each element involves a rapid transition.

"I'm a poor swimmer and need to learn how to swim properly," he said.

"To go from that to swimming 2.4 miles in open water is pretty scary because I can't really swim at the moment.''

Alan has chosen to enter the Austrian-based competition in June 2027, because he believes it is ''one of the easier'' routes, as the marathon leg features fewer hills than its European counterparts.

However, the swimming section takes place in a lake rather than the sea, which he said could prove trickier as freshwater is less buoyant than sea water.

Alan has set a target of raising £100,000 for The Brain Tumour Charity, and his training videos have clocked up more than 10 million views on social media.

''Most people die within a year of diagnosis, it's horrific," he said.

"Anything to improve that, whether it's a treatment to prolong life or a cure would be amazing."

Alan said he took inspiration from his six-year-old daughter, despite the challenges of raising her without her mother.

''Sienna is the reason I get up every morning,'' he said.

''As she started to grow older she became aware of parents dropping off their kids and she asked more questions.

"Initially I told her that her mummy got a sore head and the doctors couldn't fix her.

''We show her videos and pictures and always talk about what mummy was like.''

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