What the data actually shows
Some studies do find a small link between posture and how people feel. Work by Nair and colleagues (2015) found that people who sat upright during a stressful task reported somewhat better mood and self-esteem and less fear than those who sat slumped. Related research suggests upright posture can be associated with slightly more positive affect and energy. These effects are real in the studies but generally modest, and posture also has straightforward physical effects on breathing.
Posture's effect on how others see you is on firmer ground. Open, upright posture tends to read as more confident and competent to observers, which is a social effect independent of whatever it does to your internal state. So part of posture's value may be in perception by others rather than in changing how you feel.
The dramatic claims are where the science collapsed. Amy Cuddy's widely shared 'power posing' idea held that expansive poses raise testosterone, lower cortisol, and increase risk-taking. A replication by Ranehill and colleagues, using a larger sample, failed to reproduce the hormonal and behavioural effects; the feeling of power sometimes survived, but the physiological claims in particular did not. The episode became a well-known case study in the replication crisis.
Why this feels different from how it actually is
The power-pose story spread because it was a perfect idea: simple, free, instantly actionable, and tied to a compelling talk. A two-minute stance that rewires your hormones and confidence is exactly the kind of claim people want to be true, which is part of why it travelled so far before the evidence caught up.
It also feels different because the modest, real effect and the dramatic, debunked one get blurred together. 'Posture affects mood a bit' and 'posing changes your hormones and risk-taking' are very different claims with very different evidence, but in popular retelling they collapse into a single confident message that overstates what survived scrutiny.
And the bodily intuition is genuine. Slumping when you feel low and straightening when you feel alert is a real experience, so the broad idea that body and feeling are linked rings true. The mistake is reading that intuition as proof of the specific, large effects the original claims promised.
Posture may give a mild nudge to how you feel; it is not a hormonal hack that rewires your confidence.
What the research says to do about it
Treat posture as a small, low-cost nudge rather than a transformation. If sitting or standing upright helps you feel slightly more alert or composed in a tense moment, the modest evidence supports using it — just with realistic expectations about the size of the effect.
Lean on the social and physical effects, which are better supported. Open, upright posture tends to read as more confident to others, and better posture supports easier breathing, so there are reasonable reasons to attend to it that do not depend on the contested mood claims.
Put the bigger effort where the evidence is stronger. Mood, energy, and confidence respond more reliably to sleep, movement, social connection, and addressing underlying issues than to how you hold your body. And persistent pain, fatigue, or low mood are signals to see a qualified clinician, not to fix your posture and hope.
What the research says does not help
Relying on 'power poses' to change your hormones or boldness is not supported. The physiological and risk-taking claims largely failed to replicate, so striking an expansive pose before a high-stakes moment expecting a biochemical edge is building on a debunked finding.
Treating posture as a fix for confidence or low mood overstates a small effect. The mood links that survive are modest, and leaning on posture as the lever can crowd out the better-supported drivers of how you feel — and can delay attention to underlying causes worth proper assessment.
Obsessing over holding a 'perfect' posture all day is unsupported and can backfire. The evidence is about general tendencies, not rigid maintenance, and constant tense self-correction is more likely to cause strain and self-consciousness than to improve how you feel.
The most important 'number' here is a negative result — the famous power-posing effects did not survive a larger replication.
What this looks like in real life
'Sit up a bit' vs 'pose your way to power'
'Posture affects mood a little' and 'a two-minute pose rewires your hormones and risk-taking' are very different claims with very different evidence. The first has modest support (Nair and colleagues, 2015); the second largely failed to replicate in a larger sample. In popular retelling they collapse into one confident message that overstates what actually survived scrutiny.
Before a high-stakes meeting
Standing tall for a moment beforehand may genuinely help you feel a touch more composed, and it reads as more confident to the people in the room — both reasonable, supported reasons to do it. What the evidence does not support is expecting a biochemical edge from an expansive pose. The small, real effects are worth using; the hormonal hack is not there.
Real numbers in context
The honest numbers here are about effect sizes and replication, not headline statistics. In studies like Nair and colleagues (2015), upright posture was associated with modestly better mood and lower fear during a stressful task — a real but small effect, in a small sample, not a dramatic shift.
The most important 'number' is a negative result: the high-profile power-posing claims about testosterone, cortisol, and risk-taking did not survive a larger replication (Ranehill and colleagues), which is why this case is so often cited in discussions of the replication crisis. So the trustworthy reading is small effects of posture on how you feel, firmer effects on how others perceive you, and dramatic hormonal claims that the evidence does not support. Be skeptical of any source promising big confidence or hormone changes from a pose.
Educational only — not medical advice. For persistent pain, fatigue, or low mood, see a qualified clinician.