Power posing is considered debunked, despite 70 million views.
In 2010 Carney, Cuddy and Yap reported that two minutes in an expansive pose raised testosterone and risk-taking. A 2015 replication with 200 people instead of 42 found no hormonal effect. In 2016 first author Carney publicly stated she no longer believed in the effect. At most a feeling of power remains; hormones and behaviour don't change.
Useful: A spectacular TED talk isn't evidence; check sample size and replications.
Source: en.wikipedia.org