I trained with Crossfit star Sara Sigmundsdottir for just 20 minutes, and she kicked my butt even though I work out 6 days a week

• I worked out with top CrossFit athlete Sara Sigmundsdottir at WIT Training in London.
• Sigmundsdottir had already trained for four hours that day, but she still annihilated me.
• Her fitness is impressive, but I was most wowed by her grit, dedication, and mental strength.
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"How long a workout shall we do? An hour?" CrossFit athlete Sara Sigmundsdottir asked me.

"Maybe a little less," I suggested. And I was very glad I did.

I trained one-on-one with Sigmundsdottir for 20 minutes, and she absolutely annihilated me – despite still recovering from the devastating ACL injury which stopped her from competing in the 2021 CrossFit Games.

CrossFit encompasses a range of disciplines, requiring strength, speed, endurance, agility, and more.

Sigmundsdottir, now 28, took up the sport at the age of 17, and went on to finish 3rd at the CrossFit Games in 2015 and 2016.

I didn't find out until after our workout that the Icelandic CrossFitter had already trained for three to four hours that day.

Sara Sigmundsdottir is one of CrossFit's most popular athletes

Sigmundsdottir is currently in London to launch her first activewear collection with WIT Fitness, which is designed to help women embrace their strength and made with fabric to give muscles breathing room, she told me.

A post shared by Sara Sigmundsdóttir (@sarasigmunds)

With 1.8 million Instagram followers, 28-year-old Sigmundsdottir is one of the most popular faces in the sport, despite having not made it to the CrossFit Games podium for five years due to various injuries and setbacks.

While Sigmundsdottir and I may be almost exactly the same age, weight, and height, it's fair to say that's where our similarities end when it comes to workout stamina. I've dabbled in CrossFit workouts, but it's not my main way of training.

The workout required me to complete as many rounds as possible in 20 minutes

The workout was an AMRAP - as many rounds as possible - consisting of four exercises, divided into four four-minute chunks, with a minute of rest in between:

• 16 calories on a rowing machine
• 16 handstand walks
• 8 burpees
• 16 weighted walking lunges

The idea is you just keep going, getting through as many rounds as you can.

Unsurprisingly, the handstand walk is not a tool I have in my fitness arsenal, so Sigmundsdottir said I could substitute them for push-ups. Lucky me.

We prepared our equipment - Sigmundsdottir opted for a 15kg (33lbs) dumbbell, I went for 10kg (22lbs) - and warmed up with a few reps of each exercise. Sigmundsdottir gave me some pointers on my rowing technique.

And then it was time to start the clock and get cracking.

Watching Sigmundsdottir's handstand walks in real life was inspiring

At the start, I thought I was rowing at the same pace as Sigmundsdottir. It quickly became clear I was not.

I couldn't stop watching Sigmundsdottir. As someone who's watched the CrossFit Games on TV, seeing one of its stars performing right in front of my eyes was incredible. The handstand walks were particularly impressive, and she made them look so easy.

As I got tired, my push-ups dropped to my knees, my lunges weren't as low as they should have been, and I may have accidentally miscounted my burpees.

Sigmundsdottir had lapped me, and as I pointed this out, she said: "If you can talk, you're not working hard enough."

Sigmundsdottir's mental strength impressed me the most

Despite the fact that this was a bonus workout for Sigmundsdottir rather than one of her actual training sessions, her mental focus and drive was astounding. She cheered me on, and I felt like I didn't want to let her down.

I'm not averse to working hard, but athletes like Sigmundsdottir are able to push themselves to another level, and that's how they end up at the CrossFit Games.

I might stick to my chatty workouts - with long rest periods.