Last year I took part in the Angkor Wat International Half Marathon and astonished myself by actually managing to complete/hobble the full 21k. But this year – older and perhaps wiser – I decided to take it easy and just run the 10k.

I also decided to run it with a team this time, joining Angkor Hospital for Children’s Team Heart to raise money for much-needed surgery for thousands of children.

So on Sunday morning I found myself at Angkor Wat at 6am, still blinking myself awake, milling around with a small group of similarly attired runners in bright green t-shirts, all of us no doubt wondering what kind of insanity had brought us to this point. The air was buzzing with the kind of energy that only 7,500-plus runners can create, and after the 21k racers had set off, it was our turn.

Running with a team is a different kind of dynamic – naturally the speedier ones (yours truly not included) shot off ahead, but a few of us ran together and whenever we passed a Team Heart member the whoops, high-fives and cries of recognition spurred us on. The route took us through the South Gate of Angkor Thom, past the Bayon and along the Terrace of Elephants, where the AHC volunteer medical team stood by and gave more yells of encouragement.

Dressing-up in crazy costumes is a bizarre yet fun part of the marathon tradition, and along the way I spotted the usual suspects – my favourite, Aubergine Man, in what must have been an unbearably hot outfit, waving a sprig of broccoli as he ran. Plus a few new additions including a chap dressed as the Joker from Batman, a man wearing a reindeer a hat and a Christmas fairy lady, complete with tiny pointy red hat. There was also a runner pushing a pram, and another sprinting with her pet dog.

The halfway point came around before I knew it, then it was on the home straight, although it must be said the 8k mark was particularly punishing. After crossing the finishing line, my green t-shirted buddies and I caught the eye of a cameraman from a Japanese news channel who happily filmed us for a while. Then it was off for a celebratory banana and a walk through the newly installed ‘non-wet fogging’ machine for a refreshing mist of cool water.

All in all Team Heart’s 17 members raised $7,615 for AHC which will go towards the hospital’s surgical unit and operating costs.

AHC communications officer Vicky Pateman said this was the first time the hospital had formed a team, but it had been a great success and something they would look to do on a larger scale in future years.

“I definitely enjoyed it, it was really motivating running as a team,” she said. “It was really nice seeing the green t-shirts as you ran and high-fiving each other, cheering each other on.

The team loved it too and had a really good day. I think it encouraged everyone running as a team and made it more fun. It was just nice running round the temples, and as a lot of our team were international runners, it was a really special way of seeing the temples for the first time.”

The International Half Marathon definitely seems to be going from strength to strength, with 7, 579 runners taking part from 75 different countries and regions. More than half the runners were from other countries.