Sit on floor with knees bent and shins stacked with right leg on top. Use your hand to position right ankle on left knee. Ideally, the right knee will rest on the left thigh, but if your hips are tight, your right knee may point up toward the ceiling (overtime, as your hips become more open, your knee will lower). Keeping your hips squared to the front of the room, hinge at the hips and slowly walk hands slightly forward. If this is enough of a stretch, hold here, or fold your torso over your thighs to go deeper. Hold for at least 30 seconds, then repeat on opposite side.
A sedentary lifestyle can lead to having weak and tight hip flexors as they are always in the shortened position. Tight hip flexors can lead to a limited range of motion, poor posture, lower back and hip pain, and even injuries. These muscles need to get a workout when you are standing and doing movements such as raising your leg to climb stairs, run, or ride a bicycle.