No gym membership? That’s no excuse to swerve a workout. After all, if the Ancient Greeks taught us anything, it’s that an Adonis physique came long before any squat rack (or toe-curling mirror selfies).

But since the original 300 were unavailable for comment, we spoke to personal trainer Patrick McAleenan to find out just how hard an at-home bodyweight workout can be. And, it seems the subscription-free option can prove costly elsewhere.

“You can still burn fat, build muscle and work out effectively using just your body indoors,” says McAleenan. “But it is incredibly tough and will be sure to hurt the next day, so remember that this rigorous routine can always be simplified. For example, half the number of exercises if you’re struggling – 15 seconds planking or just 10 body squats – and work yourself up to the real deal.”

Which in this instance involves three complete circuits of the following, which should take no longer than an hour with a maximum of two minutes rest time in-between. This is not Sparta – it’s much, much worse.

20 x Burpees

Why: Burpees are an immense full-body exercise, working your arms, chest, quads, hamstrings, glutes and abs with every rep.

How To: “From a standing position, drop into a squat with your hands on the ground just in front of your feet. Then, kick your feet back behind you, keeping your arms extended so you are in a raised plank position. The more adventurous can throw a press-up into the mix for increased difficulty.”

20 x Bodyweight Squats

Why: Squats are an integral part to any equipment-free workout. Being a compound exercise, multiple muscle groups work in tandem to execute the movement, resulting in stronger legs while also increasing core stability.

How To: “Stand with your feet shoulder-width apart. Begin the movement by flexing your knees, sitting back with your hips. Continue down to full depth if you’re able, and quickly reverse the motion until you return to the starting position.”

20 x Walking Lunges (10 x Each Leg)

Why: Lunges may not seem as hardcore as push-ups or squats, but they improve balance, encourage symmetrical toning and boost your hip flexibility.

How To: “Begin standing with your feet shoulder-width apart and hands on your hips. Step forward with one leg, flexing the knees. Descend until your rear knee nearly touches the ground. Your posture should remain upright, and your front knee should stay above the front foot.

“Drive through the heel of your lead foot and extend both knees to raise yourself back up. Step forward with your rear foot, and repeat on the opposite leg.”

20 x Step-Ups (10 x Each Leg)

Why: Don’t mistake step-ups for housewife aerobics – they improve symmetry, balance, form and, if done properly, can increase your squat and deadlifting strength.

How To: “Use stairs, steps or a park bench. Keeping your chest up and shoulders back, push your body up with your left leg until straight. Pause, and then lower both feet (right, then left) to the floor. That’s one rep, then repeat.”

10 x Tricep Dips

Why: Dips are a relatively small compound exercise that’ll go big on your chest and triceps, toning arm muscles and improving strength.

How To: “Position your hands shoulder-width apart on a secured bench or stable chair, and slide your bottom off the front of the bench with your legs out in front of you. Straighten your arms, keeping a little bend in the elbows to maintain tension in your triceps.

“Slowly bend your elbows to lower your body toward the floor until your elbows are at about a 90-degree angle. Once you reach the bottom of the movement, press down into the bench to straighten your elbows, returning to the starting position.”

10 x Alternating Staggered Push-Ups

Why: Staggered push-ups recruit multiple muscle groups and joints, building strength, endurance and stability across the entire upper body

How To: “Get into a traditional push-up/plank position, but adjust your hands so that one is slightly further forward than the other. Lower your body to the ground, keeping your core tight and elbows close. Once your chest touches the ground, pause, and then press back up to the starting position. Reverse arm position and repeat.”

30 Second Plank

Why: Planking offers core conditioning like no other move, supporting proper posture while working your glutes and hamstrings.

How To: “Plant the hands directly under the shoulders (slightly wider than shoulder-width apart) like you’re about to do a push-up. Ground the toes into the floor and squeeze the glutes to stabilise the body. Your legs should be working in the move too; careful not to lock or hyperextend your knees.

“Hold for 30 seconds and, as you get more comfortable, increase for as long as possible without compromising form or breath.”

Advanced Extra: 10 x One-Legged Squats (Each Leg)

Why: One-legged squats are difficult for even the most seasoned of gym rats. Should you pull them off, however, they boast an intense, lower-back friendly workout for glutes, hamstrings and quadriceps.

How To: “This should only be attempted if you’re well-versed and in good shape. Stand in front of a pole, door frame or any other sturdy vertical object that allows you to reach your opposite leg around it. Grasp the object with both hands, and lower yourself down to the bottom of the pistol position with the heel of your squatting leg remaining flat on the floor.”

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