How and Why to Use All 3 Planes of Motion to Improve Your Mobility

How and Why to Use All 3 Planes of Movement to Improve Your Mobility

The sagittal plane is the most common one used for hip flexion movements. Hip extension movements are performed with the gluteus maximus (the big butt muscle) and hamstrings. The lumbar spine is not involved in these movements. In fact, it does not even move at all!

The frontal plane is the most common one used for shoulder flexion movements. Shoulder extension movements are performed with the serratus anterior (the big upper back muscle). The cervical spine is not involved in these movements either. However, it moves slightly forward during the movement.

In order to perform any type of hip or knee extensor exercise, you need to have access to both planes of motion: sagittal and frontal. If you don’t have access to them, then your exercises will be very limited.

You might think that the frontals are always going to be better than the sagitals because they’re closer to your center of mass. But if you look at the human body from a biomechanical point of view, it’s actually true that the frontal plane is superior to the sagital plane when it comes to hip extension movements.

The gluteus maximus is the biggest muscle that you have, and it’s in the sagital plane. This muscle is what drives your hips forward, and its main function is hip extension or straightening of the leg. The problem with this muscle is that it attaches to the back of your thigh bone, or the femur. The femur has a large angled head, which means that the angle at which it comes out of your hip capsule is very narrow, or obtuse.

The term obtuse is defined as a 90-degree angle or greater. In this case, the head of your femur angling out at more than a 90-degree angle from your hip joint. Since the femur head comes out at this very wide angle, it hits the acetabulum (or the socket) prior to the joint being fully extended. This causes the hip not to extend fully, which stops your leg from being able to go all the way straight.

This is known as hip impingement.

This is a problem for your sagital plane muscles because they attach on the back of the thigh bone, and if the hip doesn’t fully extend then these muscles don’t either.

The frontal plane has a few muscles that cross the hip joint. The main ones are the gluteus medius and the tensor fasciae latae (TFL). The gluteus medius is your “side butt muscle.” It attaches on the side of your hip bone and the back of your thigh bone.

When it contracts it causes your hip to abduct (move your leg out to the side away from the other leg). The TFL attaches on the front of your hip bone and the front of your thigh bone. It causes adduction (your leg is moving towards the midline) and also flexes (or brings the thigh forward) the hip.

Both of these muscles are in the frontal plane, and they attach to the thigh bone on one end and to the hip bone on the other end. Since they cross the hip joint, they can shorten the length of your thighbone by moving it closer to the hip joint, which brings the femur head away from the acetabulum. This allows you to bring your leg all the way straight without hitting your hip joint.

How and Why to Use All 3 Planes of Motion to Improve Your Mobility - Picture

When you have access to these muscles and can fully contract them, then you can freely bring your leg straight forward, which is required for performing a good hip extension exercise. If you don’t have good frontal plane control of your hip, then the sagittal plane gluteus maximus will take over in order to move your leg. When this happens, the large gluteus maximus is no longer able to over-power and fully extend your hip.

These sagittal plane muscles can’t bring your leg straight forward without hitting your hip joint first. The large muscles of your hips aren’t able to shorten the length of your thigh bone and take it away from the head of the femur, so you can’t bring your leg straight out in front of you.

Consequently, you compensate by throwing your leg out to the side in order to bypass the hip joint and allow your thigh bone to come away from the head of your femur. By doing this, you are no longer developing your frontal plane musculature as well since they aren’t engaged in the movement. Additionally, these muscles can become short and stiff from constantly trying to fight against your obtuse femur head.

If you utilize the sagittal plane muscles, then you won’t be able to bring your leg straight forward which is required for performing a good hip extension exercise like the barbell hip thrust and back hip extension.

Because these sagittal plane hip muscles are used all the time in daily life and in most athletic endeavors, then it’s critical to strengthen them with specific exercises. If you don’t, then these muscles will always be weak and you won’t be able to produce as much force with them. Your range of motion will also be decreased since these muscles will continually inhibit you from achieving proper positions.

The frontal plane muscles can also become short and stiff if they aren’t engaged. By using the frontal plane muscle to bring your leg straight forward, you will be able to perform a better quality hip thrust.

Another benefit of training your frontal plane musculature is improved daily functional movement. Training for function is always important when it comes to exercise.

When you do a good hip thrust, you should bring your thigh parallel to the ground. If you can’t achieve this position then part of the problem could be that you aren’t engaging your frontal plane musculature as much as you should. Frontal plane weakness can also be a limiting factor in lunges, split squats, and single leg movements in general.

If you don’t bring your thigh parallel to the ground on a regular basis, then your frontal plane muscles are probably too weak to perform this task. If this is the case, then you need to exercise these muscles to increase their strength and range of motion.

Hip thrusts are a great exercise for targeting these muscles, however another effective exercise for targeting these muscles is the straight leg toe touch.

To perform this exercise:

Stand with your feet shoulder width apart and your arms at your sides Hold on to something if you need extra support While keeping your back straight, bend at the hips and slowly reach forward and try to touch your toes. You should feel a strong contraction in the front of your thighs. Slowly pull back up to the starting position. Don’t throw your back out.

Sources & references used in this article:

The Body in Three Dimensions by T Flynn – 1998 –

The role of core stability in athletic function by WB Kibler, J Press, A Sciascia – Sports medicine, 2006 – Springer


Joint mobility and routing for lifetime elongation in wireless sensor networks by J Luo, JP Hubaux – … IEEE 24th Annual Joint Conference of the …, 2005 –

Smooth is better than sharp: a random mobility model for simulation of wireless networks by C Bettstetter – Proceedings of the 4th ACM international workshop on …, 2001 –

Mobility modeling in wireless networks: categorization, smooth movement, and border effects by C Bettstetter – ACM SIGMOBILE Mobile Computing and …, 2001 –

Passports, Mobility, and Security: How smart can the border be? by MB Salter – International studies perspectives, 2004 –

Functional movement screening: the use of fundamental movements as an assessment of function-part 1. by G Cook, L Burton, BJ Hoogenboom… – International journal of …, 2014 –

Understanding human mobility from Twitter by R Jurdak, K Zhao, J Liu, M AbouJaoude, M Cameron… – PloS one, 2015 –