Running enthusiast Michaela, 44 and from Padstow in Cornwall, had been working as a nanny for a family in Wimbledon at the turn of the millennium. As one of her 'job perks', Michaela would often take the family's horses out for some exercise in a nearby forest in Effingham, in Surrey - until one particular excursion went terribly wrong.
Despite being a fairly accomplished rider, Michaela fell from the horse while riding through the forest. Although Michaela cannot remember the accident, it is believed she hit her head, causing her to sustain a traumatic brain injury that would go on to challenge her for years to come.
"I have ridden horses ever since I was a teenager," said Michaela. "On the day of the incident, I remember taking the family's horse into the forest. I can't remember what happened next or how long I was laying there. I was eventually found unconscious on the floor by walkers.
"I think the horse must have been spooked by something and bolted. I have a blurry memory of losing control of the reins and the horse not stopping. I must have fallen badly and hit my head.
"Just weeks before my accident I bought a new riding hat because the one I had previously borrowed was too big and did not fit properly. I am so glad I did. There is no question that the riding helmet saved my life."
Michaela was rushed to Royal Surrey County Hospital where she remained in a coma for a day before beginning to show signs of improvement. A week later, Michaela was transferred to the Royal Cornwall Hospital to be closer to her family.
It was not until Michaela's first week in Cornwall that a Consultant Neuropsychologist told her parents she had sustained a severe traumatic brain injury and that doctors did not know how her recovery was likely to progress.
"I returned to my family's home to recover but we had no idea whatsoever what was ahead of us or how dramatically my life was about to change," said Michaela.
"While I have not been left with any physical disability, even today the injury to my brain's frontal lobe causes me to struggle with my emotions and behaviour.
I have lost most of my old friends and even now struggle to make new ones - it makes me feel very isolated.
"The majority of people see me as a happy and smiley person and that is who I am most of the time, but if someone says something I do not like I become easily distressed and managing my emotions at these times remains a constant battle. It feels like a rollercoaster.
"My brain injury is invisible and an emotional outburst can happen without warning, which even shocks people who know me and are aware of my history. It is always a distressing and upsetting experience.
"I carry with me at all times my Headway 'brain injury survivor' card and show it to people when an unexpected outburst occurs and it immediately diffuses the situation - I don't know where I'd be without it!"
Three years ago, Michaela received a wedding invitation and, determined to lose a couple of pounds so she could fit into her favourite little black dress, she decided to take up running.
"I bought a pair of running shoes and hit the coastal paths of my neighbourhood, trekking four miles every morning six days a week in rain and shine," said Michaela.
"I had never run before but I was determined not to give up. After three months, my dress fitted perfectly!"
Michaela soon discovered that running enabled her to focus and calm her mind after an emotional outburst. Having finally taken control of her life after brain injury, Michaela decided her running would not stop there and she eventually joined a running club. She even began to compete and - to her surprise - succeed in local races.
In February, Michaela became the 8th woman out of 49 female competitors to cross the finish-line at the Cornish Pasty Race in Saltash, which involves tackling 20 muddy obstacles alongside members of the Marines and the Royal Navy.
"Running helps me so much," said Michaela. "Obstacle races are perfect for me because they are not about speed. They are about endurance, helping each other and not giving up. Laughing, getting really muddy and having lots of fun is also brilliant!
"I want to make the hidden effects of brain injury visible to those people who don't understand the subtle daily challenges such injuries can cause. Hopefully, it will generate more empathy and support for individuals living with a brain injury.
"Now, whenever I see a person on a horse or bike without a helmet it makes me feel physically sick and worried.
So many people are unaware of the real dangers and lasting consequences of head injuries.
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