Only a year ago, Thomas Palmer, a 29-year-old cameraman from Hackney, was struggling with severe depression that prevented him from leaving his house.

But he has now returned to London from an ambitious adventure in Colombia, where he climbed five of the country's highest peaks and faced dangers like enduring freezing temperatures, trailing through minefields and avoiding being kidnapped and shot by army rebels.

While working as a cameraman on Ross Edgley's Great British Swim, he was inspired by the swimmer's energy and passion, and decided to embark on an adventure himself.

With no previous mountaineering experience, Thomas had originally planned to mount Colombia's top ten highest peaks, but due to extreme weather and some volcanoes being too active, he wasn't able to complete the personal goal.

His final and certainly most strenuous climb was Colombia's highest volcano - Nevado del Huila at 5,750 meters, which only 12 people have ever successfully mounted.

After days of hacking through the treacherous forests that surround Nevado del Huila, enduring physical exhaustion and surviving for more than 30 hours without any water or a lot of food, the team received news that cut their adventure short.

The Revolutionary Armed Forces of Colombia (FARC) members had set a camp further up the active volcano and were already tracking the team's movements.

To escape being kidnapped or shot by army rebels, Thomas and his crew made the difficult decision to turn back and head home.

"I was disappointed at first but I realised I was looking for a victory in the wrong place. I have personally won with my mental health and that's the most important thing", the mountaineer said.

Thomas, who says he now feels like a totally different person, hopes to inspire others who may also struggle with mental health issues "to set a goal and put themselves outside of their comfort zones".

He now plans to focus on setting up his own mental health charity, which will involve setting up pop-ups around the capital where Londoners can walk in and talk to volunteers about their problems.

To watch a video of Thomas's adventure, visit: RedBull.co.uk/adventure