Air squat to reverse lunge
The combination of squats and lunges will target all the major muscle groups of your lower body while also improving your balance as you transition between the unilateral and bilateral exercises.
Start with your feet slightly wider than shoulder-width apart, knees slightly bent and weight centered in your heels. Keeping your chest up and core engaged, press your hips back and bend your knees, lowering your glutes toward the ground in a standard air squat. When your knees are bent at or just below 90 degrees, reverse the movement, pressing through your heels to return to standing.
Once you're standing, shift your weight to your right side, pick up your left foot, and step it backward about 2 to 3ft, planting the ball of your left foot on the ground. With your torso upright, bend both knees, lowering your back knee toward the ground. Before it touches, press through your right heel to return to standing, stepping your left foot back to its starting position.
Continue the exercise by alternating between squats and lunges, switching between your right and left legs on every lunge.