I was worried. We had just finished the warm-up and my legs were already burning.

A group of Post reporters has signed up for the gruelling Spartan Race taking place in Hong Kong on April 14 and we were about to start our first training session. I was already tired.

The Spartan Race is a long-distance obstacle course. Competitors hang, swing, lift, carry and jump their way through 6 kilometres.

Obstacles include monkey bars and crawls under electric wires – any failed obstacle results in 30 burpees.

Trainer Andrew Power was planning a session of hill sprints up Wan Chai Gap Road, an intimidating steep slope, but first he had us running up and down stairs, two steps at a time.

“When you train hard with short bursts of power, your body needs to be ready,” Power said, justifying the vigorous warm-up.

“Over short distances and short bursts you will be focusing on power through the legs and you’re going to be pushing to your max. Without a warm-up you massively increase your risk of injury.”

We ran up and down the steps for 60 seconds, and the did dynamic stretches in between, such as lunges or holding deep squats to release the hips.

With the warm-up over, we embarked on 30-second sprints, followed by 60 seconds of rest, 12 times in a row.

You can vary the length of time you sprint and rest – elite Spartans sprint for 60 and rest for 30 seconds, according to Power.

“Running is important because first of all you want to build a good cardiovascular base, but when you run hill sprints you also build lower body muscular endurance,” Power said.

“That’s really important because during a Spartan Race you will have to do a lot of jumps, carry a lot of heavy weights up hill and burpees.”

Each sprint started at full pace, but my legs would grow heavy and I would slow. The steep hill caused a build-up of lactic acid in my quads.

“The reason I chose hill sprints, rather than sprints on the flat is I wanted to prepare you for varying terrain and gradient,” Power said, adding that training outdoors prepares you mentally for the varied temperatures and conditions on the course.

“If you are training in an air-conditioned gym, you won’t have the correct preparation, not only physically but mentally,” he said.

With the sprints over, our minds turned to breakfast but Power insisted we stay and stretch.

“If you push yourself hard, your body and muscles are going to take time to recover. But you can increase the speed of that recovery with a warm down,” he said.

“If you don’t stretch you might not be able to work again for a few days, and you won’t be able to compound your work and make those gains.”

We held static stretches, firstly leaning forward and pressing our heels down for our calves. Then, we crossed one leg over the other knee and squatted to stretch our gluteus.

Tired and sore, but with a natural post-workout buzz, the team’s attention moves to next week’s session, focused on muscular endurance.