MUSCLE OF THE MONTH: QUADRATUS LUMBORUM
In this blog we look at the quadratus lumborum, also known as the QL. Because of its position on the side of the trunk, personal trainers should be aware that clients will often not work it as much as other core muscles.
THE ORIGINATION AND INSERTION OF THE QL
Located in the lower back on either side of the spine, the quadratus lumborum muscles originate in the iliac crest of the pelvis and the iliolumbar ligament and insert into the 12th rib and the transverse processes of the upper fourth lumbar vertebrae.
THE ACTION AND BASIC FUNCTIONAL MOVEMENT OF THE QL
The QL has the following key actions:
- Lateral spine flexion, when the body bends at the waist, either to the right or the left, eg picking up an object from the floor when seated
- Waist rotation, when twisting the body from side to side
- Fixing the 12th rib during deep respiration, aiding singing technique
- Helping to extend the lumbar part of the vertebral column
COMMON EXERCISES FOR THE QL
To exercise a client’s quadratus lumborum, a personal trainer can set isometric exercises that involve unilateral loading. Isolating the muscle training is particularly beneficial when one side is weaker than the other.
Common exercises to work this important muscle group include:
Side plank – this will target the quadratus lumborum and the internal and external oblique muscles. The client should lie on their side on a mat, with one leg directly above the other. With the lower forearm on the floor, extended in line with the shoulder, and the abdominal muscles tightened, the hip should be raised off the floor, while keeping the body straight. Hold in position for 15 seconds, repeating five times a day.
A variation on this is the side bridge, when the hips are raised and lowered in sets of eight to 12, fives sets a day. To increase the intensity, a personal trainer can add a small weight on the top hip as the client carries out the movement.
Asymmetric kettlebell carry – This is when a kettlebell is held in one hand with a bent elbow bringing it to shoulder level, resting it on the upper arm. Keeping a straight spine, the client should walk 12 paces forward; repeating the exercise three to five times a day. Because they will be working hard to keep the spine straight, this will strengthen the QL muscles on the opposite side to the weight being carried.
THE BENEFITS OF QL EXERCISES
A personal trainer or sports conditioner will set QL exercises to help sports people with their training, as well as individuals looking to enhance exercise performance. This is because the starting point is to increase core stability, building up to dynamic stability through unilateral loading, asymmetric lunges etc.
Sports that particularly benefit from QL training include:
- Gymnastics – especially pommel horse exercises
- Tennis – in particular when serving
Another group of people that a personal trainer may work with on QL exercises is fire fighters, as they are often required to carry different weighted loads, or one heavy load on one side of the body.
PROBLEMS ARISING FROM UNDERDEVELOPED QL MUSCLES
Because it attaches to the lower back and the hip, a weak quadratus lumborum can cause stress and strain in the lower back muscles and referred pain to the lower back, the hip and the gluteal area (see our blog on Lower back pain and Tests to assess and monitor sacroiliac joint dysfunction).
Fitness instructors should therefore ensure they don’t overlook this muscle when setting exercise routines for clients, especially those who need to work on strengthening their back muscles. Personal trainers could also recommend side stretches for those who spend long periods seated while at work.