By Will Duru, BSc (Hons) Sport and Exercise Science, Award-Winning Personal Trainer
Got 30 minutes? That’s all you need.
No fluff. No wandering around the gym floor wondering what’s next. Just one circuit, repeated as many times as you can, until the clock runs out.
I call this one the Full-Body Engine. It’s a 12REPS staple, and I still use it myself when my week gets tight. Two cardio machines, a pair of dumbbells, and your own bodyweight. That’s the whole kit list.
Let’s get into why this style of training works so well, then I’ll hand you the full session.
Why This Format Works
Why This Format Works
Here’s a question worth asking. Why mix cardio machines with dumbbell strength moves in one block, instead of doing them separately?
Because your body doesn’t know the difference. It just knows it’s working hard.
This style is called circuit-based resistance training, and the research on it is strong. A systematic review and meta-analysis found that circuit-based resistance training produces real, measurable gains in both strength and cardiorespiratory fitness at the same time (1). You’re not choosing between getting stronger and getting fitter. You get both, in one session.
Time also matters, and I think that’s what matters most if you’re reading this on your lunch break. A study comparing circuit-based training against traditional strength training found that circuit training can cut your total training time by around 66 percent, while still driving up aerobic fitness and metabolic response (2). Less time in the gym. Similar, sometimes better, results. That’s not a gimmick. That’s just smart programming.
An AMRAP format, “as many rounds as possible,” takes this further. You set the clock, you move through the circuit, and you keep going until time’s up. No standing around checking your phone between sets. Your heart rate stays up, your muscles stay working, and you leave having done real work in a short window.
Perhaps the biggest win here, though, is the simplest one. You’ll actually do this workout. Thirty minutes, straight after work, no excuses.
What You’ll Need
- A ski erg
- A rowing machine
- A pair of dumbbells
- A bit of floor space
That’s it. No machines to queue for, no equipment changeovers halfway through.
Learn The Moves Before You Start
I’ll say this every time, because it matters. Learning an exercise shouldn’t feel like guesswork.
That’s why every exercise inside the 12REPS app comes with two videos:
- A full exercise demonstration, so you can see exactly how the movement should look.
- A coach-led technique video, where I walk you through the setup, the form, and the common mistakes to avoid.
Our goal with 12REPS is simple. Help you feel competent, confident, and prepared every time you step into the gym. Better guidance means better training, fewer unnecessary setbacks, and more confidence to keep progressing toward your goals.
Learn every exercise. Train with confidence. Keep progressing with 12REPS.
Warm-Up (5 Minutes)
Get your hips, shoulders, and core switched on before you touch a machine or a dumbbell.
Move | Reps / Time |
Walkout to World’s Greatest Stretch | 5 reps each side |
Walkout to Pigeon Stretch | 5 reps each side |
Figure 4 Stretch | 30 seconds each side |
Each of these has a step-by-step video in the app too, so you’re never left guessing.
The 12REPS Full-Body Engine
Here’s the session. One round is nine moves. Work through the round, then go straight back to the top. Keep going until 30 minutes is up.
Move fast. Keep your form. Complete as many quality rounds as you can in 30 minutes.
Exercise | Reps / Distance | Weight | Rest |
Ski Erg | 300m | N/A | None, move straight on |
Jump Squat | 12 | Bodyweight | None, move straight on |
Push-Up (or Knee Push-Up) | 12 | Bodyweight | None, move straight on |
Rowing Machine | 300m | N/A | None, move straight on |
Alternating Dumbbell Snatch | 12 (6 each arm) | Light–moderate | None, move straight on |
Alternating Dumbbell Reverse Lunge | 12 (6 each leg) | Moderate | None, move straight on |
Rowing Machine | 300m | N/A | None, move straight on |
Dumbbell Bent-Over Row | 12 | Moderate | None, move straight on |
Dumbbell Push Press | 12 | Moderate | Rest 60–90 sec, then start your next round |
A word on weight. Pick dumbbells you can control through every rep, even on round three or four when you’re tired. This isn’t the place to chase a heavy single. It’s the place to keep moving well for 30 minutes straight.
Cool-Down (5 Minutes)
Bring your breathing back down and stretch out what you’ve just worked.
Stretch | Time |
World’s Greatest Stretch (held, no walkout) | 30 seconds each side |
Pigeon Stretch (held) | 30 seconds each side |
Figure 4 Stretch (held) | 30 seconds each side |
Slow breathing through every hold. Don’t rush this part either.
How To Build This In The 12REPS App
- Open the app and go to Build Your Routine.
- Add all nine exercises in order, exactly as they appear above.
- Save it as one session, ready to load whenever you’re short on time.
- Use the app’s built-in stopwatch for your 60 to 90 second rest at the end of each round. No guessing, no checking your phone mid-set.
- Before your first round, tap into each exercise and watch the demo and coach-led technique videos. It takes two minutes and saves you from bad habits later.
You can track and build your routine on the 12REPS app with whatever equipment you have. No ski erg? Swap in 300m of running on the spot or a set of burpees. The format still works.
Is 30 Minutes Really Enough?
I get this question a lot, and I understand why. Thirty minutes doesn’t feel like much on paper.
But it’s not about the number on the clock. It’s about what you do inside it. A well-built circuit, done with intent and no wasted time between moves, gives your heart and your muscles a proper training stimulus. The research backs this up, and so does a decade of watching clients get stronger and fitter on sessions exactly this length.
So here’s my honest answer. Thirty focused minutes, twice a week, beats an hour you keep skipping because it feels like too much. Consistency wins, every time.
Open the app. Build the routine. Set your 30 minutes. Go.
References
- Muñoz-Martínez, F. A., et al. Effects of Resistance Circuit-Based Training on Body Composition, Strength and Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis. Available at: nlm.nih.gov/pmc/articles/PMC8145598
- Alix-Fages, C., et al. Acute Physiological Responses to High-Intensity Resistance Circuit Training vs. Traditional Strength Training. Available at: nlm.nih.gov/pmc/articles/PMC7695212
