Could this be the case of missing the forest for the trees? Perhaps the burnout is happening due to stagnant wages and inflation which forces people to work longer or take up additional unfulfilling jobs. Exercises perhaps may only be helping in workers handle additional stress but doesn't improve their being on the whole.
Productivity vs Hourly Wage [0]
GDP vs Median household income [1]
[0] http://www.decisionsonevidence.com/wp-content/uploads/2011/0...
[1] https://upload.wikimedia.org/wikipedia/en/e/e2/US_GDP_per_ca...