Why Muscles Shake in Yin Yoga
By Bernie Clark
November 1, 2025
“I am relaxing into the pose and all of a sudden, my legs start to shake! What’s going on? This is yin yoga? Why am I shaking?” If you are a yin yoga teacher, you may have had a student ask you this question, and even if you are not a teacher, you may have experienced this weird muscular shaking in your own practice. You are doing yin yoga! You are fully relaxed. And, yet, your muscles are twitching all over the place. Why? The first thing to do is to assure your student, and yourself, that this is normal, harmless and can be a way to deepen your practice. Once everyone is calm, you can start to explain what is going on.
Why do we shake in active practices?
When we are doing strong, yang activities such as holding challenging poses like Side Plank or Boat Pose, or after lifting weights, your muscles may begin to quiver uncontrollably. Shaking can occur when our muscles are working harder than normal or learning something new. A few things can be happening:
Your muscles get tired
As they fatigue, the nerve signals that control our muscles become less regular. The muscle fibers start firing in bursts rather than smoothly, producing rhythmic oscillations. This is known as physiological tremor and it manifests as visible trembling. Sustained isometric contractions amplify these fluctuations.1
Your body is learning a new skill
When you try a movement that’s unfamiliar, your brain sends extra signals to the muscles to make sure you don’t fall or lose balance. Often, it turns on both the muscles that move you and the ones that oppose the movement at the same time—like tapping the gas and the brake together. This double effort makes you shake, at least until your nervous system creates a better activation pattern.
With practice, the shaking goes away
Once your brain learns how much effort is needed, the signals become smoother, the work more efficient, and the trembling fades or never begins at all.
When you see students shaking in an active posture, it usually means they are working near their limit or edge and the body is learning new coordination.
Why do we sometimes shake in a yin yoga pose?
But what about shaking in Yin Yoga, where the goal is to relax the muscles? How can the body tremble when it’s supposed to be soft? Well, even when we think we’re not using a muscle, it never truly switches off. A small amount of tension is always present to hold our shape and protect joints (this is called muscle tone). If that background tension fluctuates slightly, the muscle can start to quiver:
Natural resonance
Every limb, like a guitar string, has a frequency at which it naturally vibrates. Tiny pulses from the nervous system or the heartbeat can set off small oscillations that look like shaking, especially when the muscles are partly stretched.
Thixotropy
Here is your new word today: thixotropy.2 Thixotropic materials that are stiff can be made to relax when they are shaken or stirred, but if they don’t move, they become stiffer. Muscles are made of microscopic fibers that behave a bit like honey or toothpaste: thick when still; softer when moved. When you slowly stretch and hold still, the fibers adjust to their new length, sometimes in small jumps. This settling process can appear as tremor.
Sensory feedback
Muscles contain sensors, called muscle spindles, that monitor stretch. Sometimes, when you move into a long hold, these spindles briefly overreact, sending a signal to tighten the muscles, then release, then tighten again. That alternating pattern can look like twitching. Usually, it passes after a few breaths as the system recalibrates.
Arousal or environment
Trembling also increases when we’re cold, anxious, or trying too hard. A chilly room, caffeine, or self-consciousness can magnify even tiny muscle movements.
So, even in stillness, the body is far from static. It is quietly balancing, adjusting, and refining. The shaking is part of that ongoing process.
What to tell students?
Everybody shakes sometimes. If a student is concerned or it happens constantly, advise them to see a health care professional. If the shaking continues class after class and in different areas each time, or occurs outside of yoga practice, it may reflect a medical condition, such as thyroid imbalance, electrolyte deficiency, medication side effect, or a neurological disorder.3 But, for the vast majority of cases, an occasional bout of shaking is normal and benign.
We can use the shaking, twitches, and tremors to deepen our practice. In yin yoga, we have time. Time to observe…without reacting to what is going on. If you are experiencing shaking, watch it. Allow your breath to slow and become calm, and notice how long it takes for the tremors to subside as you relax more deeply. Rather than trying to “fix” the shaking, we can invite curiosity. The body is revealing a dialogue between effort and surrender, between the nervous system and gravity.
Sometimes, however, the shaking is relentless. No matter what you do or how patient you are, your body keeps jumping. In that case, smile and surrender. Change your pose a bit; often one particular angle or depth in a pose is what triggers the tremors. If you change the pose slightly, everything becomes quiet and still.
In the end, a little shaking in stillness is not a sign that something is wrong. It is simply the body’s way of communicating as it learns and adapts. When we meet those small movements with patience and awareness, the trembling often softens on its own, leaving a deeper sense of steadiness and ease.
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1 Here are a couple of studies to explore if you’d like to dive deeper into this “shaky” topic:
- Contessa & De Luca, Journal of Applied Physiology (2009): muscle fatigue increases small rhythmic tremors. https://journals.physiology.org/doi/full/10.1152/japplphysiol.00035.2009
- Heald et al., Scientific Reports (2018): early learners co-activate muscles until coordination improves. https://www.nature.com/articles/s41598-018-34737-5
2 Thixotropy is a scientific term that describes how certain materials change their consistency depending on movement. A thixotropic substance is thick and sticky when it’s still, but becomes softer and more fluid when it’s moved or stirred. You can think of honey, ketchup, or toothpaste. They resist movement at first, but once you start stirring or squeezing, they flow more easily. Muscle fibers behave in a similar way. When a muscle has been still for a while, its protein filaments and surrounding connective tissue stick together slightly, making it feel stiff. As you begin to move or stretch, those internal bonds loosen and the tissue “melts” into motion. During this transition, the nervous system may send little bursts of adjustment that can make the muscle twitch or tremble for a few seconds. “The stiffness of a muscle is temporarily reduced after a twitch contraction.” See Lakie, Clinical Biomechanics (2019): review on muscle “thixotropy” and how stiffness changes with use. https://journals.physiology.org/doi/full/10.1152/japplphysiol.00788.2018
3 If shaking continues class after class, even in gentle postures, it may point to an underlying medical issue. Possible causes include electrolyte imbalances (especially low magnesium, calcium, or potassium), thyroid disorders, nerve compression or neuropathy, essential tremor, medication side effects, or neurological conditions such as Parkinson’s disease or multiple sclerosis. Occasionally, chronic stress, anxiety, or fatigue can also amplify tremor activity. If the shaking persists or occurs outside of yoga practice, it’s wise to consult a healthcare provider.