I tried Arnold Schwarzenegger's "double trouble" workout and it was surprisingly accessible

To the uninitiated, the terms "Arnold Schwarzenegger" and "accessible workout" might sound odd in the same sentence. But the seven-time Mr Olympia winner has worked for decades to make fitness fun and accessible for all.

One of his most recent innovations, the aptly-named Arnold's Pump Club newsletter, contains a bodyweight workout challenge for subscribers to try each Monday. And after spotting this particular one in my inbox, I couldn't resist taking it for a spin—it only uses four bodyweight moves and takes less than 20 minutes, but it's surprisingly challenging.

How to do Arnold Schwarzenegger's 'Double Trouble' bodyweight workout

This workout is called "Double Trouble" and you'll soon see why. There are four bodyweight exercises to try: squats, inverted rows, push-ups and reverse lunges. (If you don't have access to a bar for inverted rows, switch them out for bent-over dumbbell rows instead.)

To begin, perform each of the four exercises in turn for two repetitions each. Next, repeat this sequence, but double the amount of repetitions, so you're doing each move four times. Keep doubling the number of repetitions until you're performing each exercise eight times as a minimum, or 48 as a maximum, depending on your fitness level.

Schwarzenegger suggests you stop when you can't complete at least half of the prescribed repetitions for any of the exercises.

You can take your time with this workout or try to finish it as quickly as possible. If you want to add a competitive element, you can also set a running clock and record your time and total rounds as a score to beat in future.

Five things I liked about the workout

1. It lures you in

This is a deceptive workout—and I say that as a compliment.

Most people can manage two bodyweight squats without breaking a sweat and this unassuming start eased me into Arnold's challenge.

Yet just a few minutes later I found myself facing down a large set of 32 squats, followed by the same number of inverted rows, push-ups and reverse lunges.

This is a clever piece of programming from Schwarzenegger and his newsletter team, luring you into taking on a challenge that seems easy to begin with, but quickly ramps up the difficulty level.

2. It's adaptable

Another thing that really impressed me about this workout was the scaling options for different fitness levels.

Taking on the challenge during my lunchbreak, I tackled five rounds, which meant that I finished by doing 32 repetitions of each exercise.

If you're a fitness fiend wanting to really push yourself, you can do a final sixth round with 48 repetitions. Or, if you're new to strength training, you can tackle three rounds and do eight repetitions of each move.

You can alter the exercises too. If you're still working up to your first push-up, you can place your hands on an elevated surface or lower your knees to make it slightly easier.

And if you don't have a bar for the inverted rows, you can swap them for bent-over dumbbell rows, which will still switch on your back and biceps muscles.

3. It highlighted my weaknesses

This is a full-body workout; the squats and reverse lunges hit my lower body while the push-ups activated my chest, shoulder and triceps muscles, and the inverted rows worked my back and biceps.

While my thighs certainly burned after 32 fast-paced squats and lunges, I was still able to work through the repetitions without pausing. The push-ups were slightly harder, but I was able to finish the last round without any breaks.

It was the inverted rows that proved to be my downfall. On the final set I struggled to hit 16, then had to split the remaining repetitions into three mini sets to hit my 32-rep target.

This has highlighted that I need to work on my back and biceps more, if I want to progress to the next level of this challenge.

4. It challenged my muscles without weights

Call it self-belief or arrogance, I approached this workout with a lot of confidence.

Because my daily CrossFit training tends to center around heavy barbells, dumbbells and kettlebells, as well as fairly complex gymnastic exercises like muscle-ups, I figured I'd fare pretty well with Arnold's bodyweight challenge.

So I was humbled to drop out before the 48-repetition final round after struggling to reach 16 unbroken inverted rows in my final set—proof that you don't need weights to really challenge your muscles.

5. It pumps up your muscles (albeit temporarily)

The short-term result of this intense bodyweight workout is Arnold's fabled "pump"—fluids, including water and blood, flow into the working muscles, causing them to swell in size.

I enjoyed the (temporary) pump aesthetic, but I enjoyed the post-workout feel-good factor more. It's well-documented that regular exercise can improve your mood, and this session was no different.

By the end I was breathing hard and my eyebrows were working over time to keep drips of sweat out of my eyes, yet I felt elated. There's also, I find, an immense sense of satisfaction after tackling a challenge. And Arnold's workout definitely delivered that.

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