With countless Christmas parties this month, you’ll surely need to burn more calories in the gym. But if you’re not near one, here’s one surefire solution for you: Get into the buddy system. It’s proven that some friendly competition can help boost your workout intensity. So, here’s our top 4 fitness moves as tested by the Adjani brothers:

Medicine ball sit-up throw
Targets: Back, shoulders, and hips

Grab a medicine ball and sit on the floor, facing your buddy with your knees bent and feet locking each other down. Lie back with the ball against your chest then sit up and pass the ball him. Volley back and forth for about 10 times. Record the time it takes to complete a set and try to beat it.

Double planks
Targets: Entire body

This is best done after cardio. Towel off all sweat before trying this to prevent accidents. Assume the plank position and, once your stable, your buddy assumes the same position atop you but facing the opposite direction, his hands on your ankles and his feet on your shoulders, toes untucked. Hold for two minutes, then switch.

Squat and lunge
Targets: Quads, hamstrings, glutes, and calves

Hold each other accountable during leg days. Start by standing facing each other. Support each other’s weight and keep the pace up by holding each other’s right hand. Do squats as your buddy does step-back lunges first with his dominant leg then with the other. When he’s completed five reps on both legs, do the same as he does squats.

Plank and burpee jump-overs
Targets: Entire body

Hold the plank position as your buddy does burpee jumps over you. After he does 10 reps, trade places.

Photography: Mau Aguasin. Grooming: Lei Ponce of Make Up For Ever. Models: Sam and Tohid Ajdani of Mercator