This super-tough workout only uses your bodyweight, but that doesn’t mean it’s easy. You’ll feel all your muscles light up as move through short 20-second intervals followed by longer 60-second durations for a challenging HIIT routine. It features moves like alternating kick-throughs, plank shoulder taps, forward-leaning reverse lunges, and burpees — because it wouldn’t be a tough workout without burpees.

All you need to get started, according to Girvan, is your mat, a bottle of water, and a towel to sop up your sweat. Oh, and a lot of energy to spare.

While this calisthenics workout is difficult, Girvan emphasizes the importance of staying “calm and collected” so you can maintain good form and make the most of each move. To do so, she recommends relaxing your breath and focusing on the movement patterns of each exercise.

Each round lasts 30 seconds with four exercises combined to create one set. The first two exercises are repeated, she notes, so that you have time to perfect your technique. (Girvan also shares a preview of each upcoming move during the rest period so you know what to expect.)

For this workout, you’ll need a mat, a chair, and a yoga block or stepper so you can perform diver push-ups, Bulgarian lunges, saw planks, and elevated squats. As a finisher, brace yourself for 100 crunches.

As part of Girvan’s Iron series, this video is all about pumping some, well, iron. It’s set up in a slow circuit format that allows you to focus on each exercise. Girvan recommends doing each move in a controlled way, ensuring you aim for quality over quantity.

The timer is set for 40 seconds of work with 20 seconds of rest in between. Girvan uses two different sets of dumbbells: a heavier set for the first five exercises and a slightly lighter set for the final four. You’ll do three rounds of bent-over rows, static lunges, chest presses, and rear lunges that’ll make you feel like you’re on fire.

Click on this video if you’re up for a true cardio workout. You’ll do an exercise for 30 seconds, another one for 30 seconds, followed by 20 seconds of rest to equal one superset. It all adds up to 43 different exercises that don’t repeat. Girvan recommends going at your own moderate pace so that you can maintain your energy as you do moves like mountain climbers, skaters, plank jacks, and more. Again, all you’ll need is a mat, a towel, and a bottle of water as you “sweat, smile, and smash these supersets.”

Tend to feel bored during your workout? Then go for this full-body routine that never repeats a move. In it, Girvan shows you how to do compound exercises that light up more than one muscle within each rep so you effectively work your legs, core, shoulders, and arms.

Grab a pair of dumbbells and keep an eye on the timer in the corner of your screen as you do single-arm bent-over rows, goblet squats, alternating dead bugs, and more. Each move lasts 40 seconds followed by 20 seconds of rest.

If you’re down for a challenging leg workout, try this video that features 10 lunge variations — like the elevated lunge, rear step lunge, and lateral lunge — that you’ll perform 100 times to really work your hamstrings, glutes, and quads.

To get the most benefit, Girvan recommends performing each lunge as smoothly as possible through your full range of motion. If 1,000 seems like too much, there’s also the option to aim for 500 reps instead. Girvan is all about pausing for breaks whenever necessary and modifying moves to make them work for you.

Follow along with this tough ab workout to really ignite your core. Girvan notes that 10 minutes is really all you need to train this area and gain a little extra strength. “Consistency, intensity, correct form, patience, and control of every movement will contribute to overall improvements in fitness levels and training,” she says. Brace your core as you do toe-reach crunches, bicycles, reverse crunches, and alternating-side crunches.