Working for reps can sometimes be forgotten when you move into the world of group fitness, but there’s a reason that certain reps are prescribed for certain movements. Today we’re doing 12 reps and that range has been shown to be the best for building more muscle mass.

More muscles mass leads to a higher resting metabolic rate, meaning that your body burns more calories even when you’re doing nothing, according to the Mayo Clinic.

Or another way to put this that we like even better: “I like being muscular because it pays for the party,” Biggest Loser trainer and all around amazing woman, Jen Widerstrom said at a recent Shape event in Chicago.

So grab two heavy dumbbells and pay for the party. It is, as they say, the freakin’ weekend.

Here’s your workout!

With two heavy dumbbells, you’ll do 12 reps of each movement and each set of movements should take about a minute. Move slowly and with control, moving for the counts prescribed below.

• 12 Dead lifts (Down 3, Up 1)
• 12 wide rows (Up 1, down 3)
• 12 loaded squats (down 3, up 1)
• 12 bridge position chest presses (Up 1, down 3)
• 12 plank ankle taps (each side counts as 1/2 rep)
• Between rounds, 30 burpees

Here are the exercises:

Dead lifts: Starting with your feet hip-width distance and your knees bent slightly, hinge forward from your hips. As you hinge, keep your back flat and your core pulled in tightly. Lower down to the point at which your back is parallel to the floor and lift back up.

Wide rows: With your feet planted at hip width distance and your knees bent slightly, hinge from your hips, keeping your core engaged and your back flat. Hold your body in this position for the duration of this exercise. Start with the weights in front of you and your palms facing your body. Maintaining that same palm position, pull your elbows up and out to 90 degrees, pulling your shoulder blades together behind you.

Loaded squats: With your feet hip-width distance and holding one heavy weight or two at your chest, squat down, sitting back and down so that your seat is at knee height at the bottom of your range of motion. Keep you weight in your heels at the bottom of the range of motion. Stand up and squeeze your glutes at the top.

Bridge position chest presses: In a bridge position – facing up with feet planted firmly beneath your knees, your hips raised and your shoulders, hips and knees in a straight line. Bring your dumbbells into a press position with your palms facing towards your knees and your elbows bent at 90 degrees on the floor.

Plank ankle taps: In a plank position, pike your hips up as you reach your left hand beneath you to touch your right ankle. Return to your plank position and repeat the same thing on the opposite side. For this movement, each tap counts as 1/2 of a rep.

Burpees: Squat down, touching the floor and jump back into a plank. Lower down to the floor, allowing your chest to touch the floor, staying in control. Push back up, jump forward into your squat position again and jump into the air, clapping overhead.

(Disclaimer: This workout is not intended for the treatment or prevention of disease, nor is it a replacement for seeking medical treatment or professional nutrition advice. Do not start any nutrition or physical activity program without first consulting your physician.)