What Does the Single Knee to Chest Exercise Do?

The single knee-to-chest exercise is an easy way to stretch your lower back, hamstrings and glutes. Stretching can help you become more flexible and increase the range of motion in your joints. You can use this exercise to ease any muscle tension or pain in these muscle groups, or perform it near the end of your pre-workout warmup or after your workout.

To perform the single knee-to-chest exercise, lie on your back with your knees bent and your feet flat on the floor. Leaving one foot in place, bring one knee toward your chest while pressing your lower back into the floor. Hold the raised knee with both hands and then hug it toward your chest. Hold the leg in place for between 15 and 20 seconds, according to WebMD, and then reset and repeat with your other leg. You can also intensify the stretch by beginning with both legs extended on the floor instead of bending them at the knees.

Physical therapists recommend the single knee-to-chest exercise for people recovering from lower-back injuries as well as suffering from lower-back pain. And the UK-based Arthritis Research UK agrees, recommending that men and women suffering from arthritis in the lower back and hips use this stretch to ease pain and release tension in the spine. Avoid this exercise if you have osteoporosis to reduce the risk of vertebral fractures.

The single knee-to-chest exercise stretches the buttocks, or glutes, as well as the hip flexor of the leg that remains in place, according to Bodybuilding.com. Stretching your glutes and hip flexors is important, given how much each day most people sit. Sandra Hahamian, a certified personal trainer, told “Shape” magazine that sitting too long can cause your glutes to degenerate. This break down can cause pain in joints such as the lower back and knee as they compensate for the lack of gluteal support. So the more often you stretch these muscles, the better.

The single knee-to-chest exercise stretches your hamstrings, which are muscles along the back of your thighs that help you walk, run, sit and stand. A study published in the January 2010 issue of “Clinical Journal of Sport Medicine” found that active hamstring stretches, like the single knee-to-chest exercise, increased range of motion and led to more long-term flexibility benefits than static hamstring stretches, or stretches that don’t incorporate movement.

MayoClinic.com recommends incorporating the single knee-to-chest exercise near the end of your warmup or after your workout, because stretching before your muscles are warm can lead to injury. You should never force a stretch, and if something hurts, you should stop. MayoClinic.com also recommends repeating stretches in areas that are tight or injured. Your doctor can tell you if you should avoid certain stretches.