I trained like Henry Cavill every day for a week by doing fasted cardio, and I hated it and loved it in equal measure

The Witcher
(Image credit: Netflix)

Chances are, if you’ve clicked on this article, you know who Henry Cavill is: the Queen’s English-speaking, famously ripped star of Man of Steel, the Witcher and Mission Impossible: Fallout and other big action films. He’s made a big impact on the fitness scene: ‘Henry Cavill workout’ is one of the most popular fitness search terms on the internet for men of a certain demographic.  

Despite the fact I’ve never met him, I do know Henry Cavill and I share several things in common: we both love Warhammer, chunky fantasy books and running. That’s more or less where this pseudo-parasocial bromance ends: I don’t share his physique, for starters. However, with a little time, my best running watch and my best running shoes, I certainly could train like him, in the interest of trying it as a challenge to commemorate the start of TechRadar’s Get Fit for ‘24 week of fitness content.

In an interview with GQ magazine in 2020, Cavill claims to do fasted cardio up to six days a week to keep himself lean. 

He said: “Quite typically it's six days a week, I'll be doing fasted cardio, so I get up in the morning, I will have a coffee, and then I will do some cardio for half an hour, and then I'll have breakfast and then I will either go to the gym, or go to work depending.”

Perhaps I don’t have the aid of a Hollywood cottage industry of professional chefs, dietitians, private gyms and personal trainers, but I can get up and run for 30 minutes before breakfast, six days a week. I run all the time, albeit on a full stomach at lunchtimes or mid-morning on the weekends. Should be easy, right? Check out how I got on below, documented in the embedded TikTok video:


♬ Powerful songs like action movie music - Tansa

Days 1-2

I forgot how much running before breakfast, in the winter, sucks. Having had nothing but a few mouthfuls of water, I laced up and hit the road around 7am. It’s very cold in the UK, at the time of writing: around four degrees celsius and it doesn’t get light until around 7:40am. 

So not only am I running hungry each morning, but I’m also running in the cold and dark. 25 minutes drags on, and as someone who’s used to having bucketloads of energy on short runs, I’m unusually slow and tired. If you’re interested in starting your fitness journey like this, I honestly couldn’t recommend it. 

Days 3-4

Getting into the groove. I took a quick look into exactly why Cavill likes to do this to prepare for his roles, and it turns out his training goals are, surprise surprise, very different to mine. 

The prevailing theory behind fasted cardio is based on studies like this one from Cambridge University, which states that fasted cardio leads to higher fat oxidation – the process through which your body burns fat. In essence, the theory is that your body has no food in its system, so it chews up its own fat for fuel. 

I tend to run to train so that I can run further and faster, as well as to clear my head during long stretches of easy running. This is why I wasn’t enjoying the first two days: I was comparing the way I feel during my normal endurance runs, for which I’m fueled up with coffee and high-carbohydrate food, to a 30-minute cardio session designed purely to burn fat. 

Consequently, I abandoned the idea I needed to perform at my best and tried to stop getting frustrated at the lack of energy I felt during my run. I checked my Apple Watch Ultra 2 regularly and made sure to slow my pace – and found myself enjoying those quiet morning runs a lot more.  

Days 5-6

Far more enjoyable. I had gotten into the habit of Cavill’s routine, getting up and pulling on my running shorts straight away. I got out the house for my usual short running route along the river, and began to appreciate that it was just myself, the ducks and the occasional dogwalker. 

I felt self-satisfied that I had gotten up and done something when I would have otherwise scrolled through my phone or read with my breakfast for 15 minutes. I found I could switch my playlist off and just enjoy the atmosphere of the early morning on my way back (thanks to the Shokz OpenRun Pro, my best bone conduction headphones, which leave my ears open as I run).

A few knock-on things had to change with my routine: for example, I switched from my usual oatmeal to overnight oats, so I could grab it out of the fridge as soon as I finished my workout and wolf it down before shooting off to work. But overall, I didn’t lose much, if any, sleep by getting up slightly earlier, and I added 30 minutes of cardio to my day. 

Final thoughts

Since this challenge, I have not gotten up and performed fasted cardio every morning, as I’m not trying to look good for a shirtless scene in a blockbuster movie. It’s also not magically made me enjoy fasted cardio: it still sucks, and I get continually frustrated I don’t have the energy to run at my usual clip. 

However, I have gotten up to do it occasionally, probably about once a week. Since the challenge, I have also found that on days I do run before work, I can concentrate slightly better in that crucial first hour of work, although there’s no way to really measure this. 

Cavill’s training habits are obviously unsuitable for your average joe to perform on a daily basis, but it’s a great option for someone who’s struggling to fit a workout into their week and needs a little kick-start to get going again. I found 30 minutes of running or brisk walking, whether outside or indoors on one of the best treadmills, surprisingly easy to incorporate into my morning routine. It remains an option available to me. 

I’m not doing to be doing this challenge six days a week again anytime soon, in some misguided bid to look like Superman. However, on a drizzly, cold Monday morning, a little cardio – which is doubly effective when it comes to fat loss thanks to the fasted element – is just the thing to start my week on a positive, productive note.  

This article is part of TechRadar's Get Fit for '24 week of fitness content.

Matt Evans
Fitness, Wellness, and Wearables Editor

Matt is TechRadar's expert on all things fitness, wellness and wearable tech. A former staffer at Men's Health, he holds a Master's Degree in journalism from Cardiff and has written for brands like Runner's World, Women's Health, Men's Fitness, LiveScience and Fit&Well on everything fitness tech, exercise, nutrition and mental wellbeing.

Matt's a keen runner, ex-kickboxer, not averse to the odd yoga flow, and insists everyone should stretch every morning. When he’s not training or writing about health and fitness, he can be found reading doorstop-thick fantasy books with lots of fictional maps in them.