Can a single yoga session change how you feel? Here's what the research actually says...

By Sophia — MSc Student Psychology & Neuroscience of Mental Health, King's College London

Introduction

Most of us have stepped off a yoga mat feeling calmer than when we stepped on. But is that just the placebo effect? Is it a feel-good effect from doing something intentional, or is something genuinely happening in the brain and body? A study by Phansikar & Mullen, (2022) set out to answer that question, and the findings are more interesting and more nuanced than most wellness headlines would have you believe.

The study

71 adults reporting everyday stress were randomly assigned to one of three 30-minute conditions: a flowing yoga session (sun salutations, video-guided), moderate aerobic exercise such as walking, or a passive control group who watched a video. Before and after the session, participants completed measures of both cognitive performance and psychological state.

The design is genuinely strong. Having both an active control (aerobic exercise) and a passive control (watching a video) means we can ask two separate questions: is yoga better than doing nothing? And is there something specifically about yoga beyond general movement that drives any changes? That’s a much more meaningful comparison than most studies in this space offer.

What the results showed

Stress & anxiety

Significantly reduced in the yoga group vs both other conditions

Cognitive function

No improvement in memory, attention, or processing speed across any group

Subjective experience

Yoga participants reported greater flow, positive feelings, and self-efficacy

The emotional effects were statistically significant with a moderate effect size, meaningful, though not transformative. Yoga outperformed both aerobic exercise and passive rest for stress and anxiety reduction after just one session. That’s a notable finding, and it tells us something specific about yoga rather than movement in general.

The cognitive results, however, were clear: no differences between groups on any measure of executive function. One session simply wasn’t enough to shift memory, attention, or processing speed, and that’s not a failure of the study design; it’s the expected result if you understand how neuroplastic change works (more on that below).

Why did stress and anxiety improve so quickly?

The study proposes several interconnected mechanisms, and they’re worth understanding on their own terms rather than as a checklist.

Bottom-up regulation: the body leading the brain

Flowing yoga integrates breath with movement in a way that directly shifts your physiological state. Slow, controlled breathing is one of the few systems we can consciously regulate, and it has direct pathways to the brain’s arousal and emotional regulation circuitry. By slowing the breath, you pull the autonomic nervous system toward parasympathetic dominance, the “rest and digest” state, which dampens the stress response before the thinking brain even has time to catch up. This is bottom-up regulation: the body leading the brain, not the other way around.

Top-down attention: interrupting the rumination loop

Yoga demands continuous, divided attention to movement, breath, and body position simultaneously. This occupies the attentional system in a way that naturally reduces mind-wandering and quiets the default mode network (DMN), the brain network associated with self-referential thinking and rumination. Anchoring attention in the present moment is one of the core mechanisms of mindfulness, and sun salutations essentially enforce it through the structure of the practice itself.

Flow state and absorption

Participants in the yoga group reported significantly higher absorption and enjoyment, which psychologists would recognise as features of a flow state. The repetitive, rhythmic nature of sun salutations may create an optimal balance of challenge and ease: familiar enough to feel effortless, demanding enough to hold full attention. Flow states are associated with reduced self-consciousness and stress perception, and increased positive affect, which maps closely onto what these participants actually reported.

Interoception: getting better at reading yourself

Yoga may also work by enhancing interoception, the brain’s awareness of internal bodily sensations like breath, muscle tension, and movement. The insula, a key node within the salience network, plays a central role in integrating these internal signals and matching them against what’s happening externally. Importantly, these networks appear to be trainable: regular practice may improve your ability to detect early stress signals and, in doing so, give you a larger window in which to regulate them before they escalate.

Why didn’t cognition improve?

This is the result that tends to get glossed over, but it’s actually one of the most instructive parts of the study. Executive functions like working memory and attention rely on neuroplastic changes, the gradual remodelling of neural circuits through repeated experience. These don’t happen in a single session. Expecting one bout of yoga to improve cognitive performance is a bit like expecting one visit to the gym to build muscle. Longer-term practice may well produce cognitive benefits (there is emerging evidence for this), but a single acute session affects state, not capacity.

Strengths and limitations

The randomised controlled design is the study’s greatest strength; it gives us genuine causal leverage that observational research can’t provide. The dual-control comparison is particularly well-designed for isolating yoga-specific effects.

That said, the limitations matter for how far we generalise. The sample was small (71 people) and predominantly female, so we should be cautious about applying these findings to other populations, particularly men, for whom the stress-regulation mechanisms may operate somewhat differently. The video-guided format also differs meaningfully from an in-person class: the social, environmental, and teacher-presence elements of a real class may amplify or alter the effects. And because this was a single session, we have no insight into what happens with repeated practice, the question that arguably matters most for anyone thinking about yoga as a long-term mental health tool.

The bottom line

A single 30-minute sun salutation session can reduce stress and anxiety compared to both aerobic exercise and rest, with a moderate effect size and a plausible set of biological mechanisms behind it. It won’t sharpen your memory or speed up your processing after one go, but that’s the wrong expectation to bring to acute exercise research. What it does suggest is that yoga’s immediate power lies in emotional regulation: through the breath, through attention, and perhaps through something that looks a lot like flow.

As with all research in this space, this is one study with a specific sample, a specific protocol, and specific conditions. It adds to an accumulating picture rather than settling the question. If you want to try the practice itself, I demonstrate sun salutations on Instagram (@sophia_flows) — but I’d also encourage you to read the original paper linked below. The abstract is freely available, and it’s worth seeing the data for yourself.

Sophia

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References

Phansikar, M., & Mullen, S. P. (2022). Cognitive and psychosocial effects of an acute sun salutation intervention among adults with stress. Mental Health and Physical Activity, 22, 100431. https://doi.org/10.1016/j.mhpa.2021.100431