WELCOME TO the MONTHLY THROUGH LINE

Hey Chromatic family, it’s Simon here from Chromatic Yoga. It’s July 2026 and for most of us (in the northern hemisphere anyway) its a roasting hot summer! In amongst the heat and the holidays, here’s this month’s Physical Through Line. We’re still in to deep anatomical exploration, keeping our focus on muscle engagements and joint actions. After spending the month of June exploring extension, we now turn our attention to its equally important and often totally forgotten-about counterpart… FLEXION

For anyone who is new here, read on about what the CHROMATIC MONTHLY THROUGH LINES are, for you regulars, skip on to the juicy stuff! 

In Chromatic Yoga, we keep things straightforward. That’s why we’ve being doing this “Monthly Through Line” community initiative for over a year now. It’s designed to help you – our Chromatic Teachers – focus and intelligently design your classes to best support your students. If you’re not a Chromatic Teacher yet, and are simply here out of interest, that’s great too, as you’ll be able to apply these through-lines to gain more insight in to body biomechanics and potentially access the poses in a deeper and more intelligent way.

WHAT IS A PHYSICAL THROUGH LINE? 

• A Physical Through Line is a term we use in Chromatic Yoga that is defined by the muscle engagement (e.g. engaging the glutes in Warrior 3), or the joint action (e.g. hip extension in Warrior 3) that we focus on through the duration of the yoga class. Certified Chromatic Teachers construct their classes around a PTL (Physical Through Line) in order to create a more effective learning environment for students. As a student you can expect that each Chromatic class will include a PTL. Of course, you will do other postures and other muscle engagements within a Chromatic class, however there is a strong emphasis on the PTL.

Flexion – so MORE THAN a passive movement

In yoga, flexion is often reduced to forward folds and further more passive flexion/forward folds. However nice they may feel for many, spinal flexion is far more intelligent and versatile than simply bringing your chest towards your thighs passively. In fact, there is a world of active flexion to explore that brings a huge amount of functional benefit to our bodies – think abs (generic) and hip flexors. Shoulder flexion allows us to reach overhead. Hip flexion powers every squat and step. Knee flexion absorbs force and creates locomotion. Spinal flexion helps us distribute load and move with adaptability...

In reality, it’s one of the body’s most fundamental movement strategies. Every time we pick something up from the floor, bend over to tie our trainers, climb a hill, hug someone, squat down, reach up to an overhead cupboard, or absorb force during landing, flexion is playing a role.

Biomechanically, flexion decreases the angle between two body segments, but in practice it represents far more than a joint action. Flexion allows us to generate force, absorb load, create stability, and move efficiently through our environment.

Like extension, flexion rarely happens in isolation. Different joints contribute in different amounts depending on the movement, and understanding those relationships allows us to teach movement with greater precision.

This month we’ll explore how FLEXION expresses itself through the SPINE, SHOULDER, HIP and KNEE, discovering that sometimes the ability to move well isn’t about creating more space, it’s about knowing when and how to close it.

Week 1: Spinal Flexion – More Than a Forward Fold

What It Is: Spinal flexion is the action of rounding the spine, bringing the head, shoulders, and rib cage closer to the pelvis. 

Key Muscles:  Rectus abdominus, external and internal obliques when both side contract equally together.

Why It Matters: While we often think of this as “forward folding,” true spinal flexion involves segmental movement, especially in the cervical, thoracic and lumbar regions. It’s essential for developing core strength, awareness, and safe transitions. And simply in life when we bend over to tie our shoes. It also plays a huge role breath control as it influences diaphragm excursion and rib mobility. Just as we spoke last month about the importance of extension in our current desk based or predominantly sedentary biased lifestyle, active spinal flexion is fundamental where the muscles required for flexion are weak, underused and typically short.  

Where it shows up: Balasana Childs Pose, Ananda Balasana Happy Baby, Cat, Uttanasana Standing Forward Fold, Bakasana Crow Pose, Pachimottanasana Seated Forward Fold.

Week 2: Shoulder Flexion – Reaching with Intelligence

What It Is: Shoulder flexion happens when you lift your arms forward and overhead, as in Urdhva Hastasana or Downward Dog. It’s a major component of sun salutations, inversions, and any pose that involves overhead reach. Flexion at the shoulder is often limited by tightness or misalignment in the thoracic spine or lats, so awareness and support are key.

Key Muscles: Gluteus medius/minimus, tensor fasciae latae, sartorius

Why It Matters: Reaching overhead is one of the most undertrained but essential human motions. True shoulder flexion requires coordination of scapular, thoracic spine and ribcage positioning, therefore in reality, it is not an isolated joint action, but a multi segment joint pattern. 

Where it shows up: Downdog, Low Lunge, High Lunge, Handstand..

Week 3: Hip Flexion – Finding Freedom at the Front

What It Is: When the thigh moves toward the torso, like raising the leg or a knee in Tadasana (open chain) or kicking the thighs toward the ribs in Uttanasana forward fold (closed chain). It’s the basis for countless yoga poses, from Warrior III (standing leg) to Boat Pose, and also essential for seated postures and transitions. 

Key Muscles: Hip flexors (iliopsoas, rectus femoris, sartorius), with core support.

Why It Matters: Powers forward folds, hip lifts, and leg raises, creates length in the back body while protecting the lumbar if balanced with posterior tilt. With the general person having weak and or tight hip flexors from prolonged sitting, working with active and passive hip flexion helps bring functional benefit to their body. 

Where it shows up: Feel it in High Lunge (back leg pulling foward), Boat Pose, and Standing Knee-to-Chest, UHP A and Standing Splits, supine leg lifts. Explore controlled flexion without gripping the front body..

Week 4: Knee Flexion – Creating FUNCTIONAL Movement

What It Is: Flexion of the knee bends the leg, drawing the heel toward the buttocks.

Key Muscles: all the hamstrings (biceps femoris, semitendinosus, semimembranosus), whilst gastrocnemius, popliteus, gracilis and sartorius are important assisting muscles

Why It Matters: Knee flexion builds mobility and strength in the hamstrings and therefore contributes to the posterior chain, allowing safe deepening in forward folds, squats, and binds, as well as controlled transitions. In Yoga we stretch the hamstrings a lot, activating it in various poses helps create strength in the length, something that is so often missed. 

Where it shows up: 3 legged down with the lifted knee flexed, Skandasana, the back leg in King Pigeon, Twisted Monkey/Lizard with back knee flexed, Supported Bridge Settubandhasana pulling the heels toward the buttocks/shoulders. 

Check out this video created especially for you by Rebecca Doring, president of the Board of Chromatic Yoga, giving you a week by week break down of each of this months actions, as well as pose suggestions, biomechanical and anatomical insights.  

Simon’s RECAP AND TIPS

One of my favourite aspects of teaching flexion is that it encourages us to move beyond the idea that every forward fold should simply be “deeper.” Instead, ask yourself: Where is the flexion actually happening? How can I intelligently apply the action or engagement to add value, education and awareness to the students body and mind, and aid in a transformative experience.  

As Chromatic teachers, we have an opportunity to teach and educate joint actions or muscle engagements rather than simply instructing poses.

Take Uttanasana. Throw out a passive forward fold and ask, is today’s intention active spinal flexion using the abdominal muscles, while maintaining relatively less hip flexion? Or perhaps today’s objective is to bias hip flexion while encouraging students to minimise movement through the spine. The posture stays the same, but the lesson completely changes.

The same is true throughout the month. In Child’s Pose you might investigate active spinal flexion by cueing students to gently press the hands into the floor until they feel the abdominals engage. In Dolphin or Headstand, shoulder flexion becomes an opportunity to explore the relationship between the rib cage and scapulae. In Malasana, hip flexion becomes less about depth and more about creating action and engagement through organised movement.

Chromatic Yoga is a global community. No matter where you are in the world, we hope you’ll join us this month for a deep dive into the possibilities of flexion. Share/tag/collaborate your poses on Instagram. 

 Wishing you an intentional and transformative practice, 

~Simon Darroch, Director of Projects and Initiatives

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