Starting Position: Stand with your feet hip width apart. Pull your shoulders down and back without arching your low back, and engage your abdominals to stabilize your spine.
Begin to step forward slowly by lifting the right foot off the floor. Find your balance on the standing leg. Control any sideways tilting or swaying in your upper body by keeping the abdominals contracted and the standing foot pressed firmly into the ground. Hold this position briefly before reaching forward with the right foot. The right (swing) foot should contact the floor heel first. Slowly shift your body weight to the right foot, which is now placed firmly on the floor. Begin to lower yourself into the right leg. Keep your spine straight and your torso leaning slightly forward from the hips. Lower your right elbow on the inside of your right knee.
As you continue to lower yourself into the lunge, your hips should drop toward the floor. Try not to allow your hips to drive forward. This will help control the amount of forward movement of your shinbone over your foot. Place both hands on the floor. The right hand should be slightly forward of the left. Continue lowering your body to a comfortable position or until your front thigh is parallel with the floor and your shinbone is in a slight forward lean. Holding this position, push back through the left foot to lengthen and increase the stretch on the front side of the left hip. Keep the abdominals braced in order to stabilize the pelvis and enhance the stretch on the left hip flexor.
Maintaining your core engagement, push your hands into the floor and begin to return to start position. With the right (forward) foot firmly into the ground, press backwards to straighten the right knee and hip, bringing yourself forward into a standing position. Keep your chest lifted and abdominals braced to maintain a straight spine and level pelvis as you begin to swing the left leg forward to initiate the next repetition.
Continue the exercise for a specific number of repetitions or over a certain distance of travel.
Exercise Variation: to add a stretch before before stepping into the next lunge, lean back to straighten the right leg and stretch the right hamstrings. Alternate with both legs.
Focus on maintaining the abdominal bracing through the entire range-of-motion of the movement to keep the spine stable and pelvis level.