The current economic uncertainty means employees need bosses and colleagues to be more enthusiastic, according to a mobile phone network.
Workers are more likely to perform better if team leaders make an effort to put energy into their working days, according to T-Mobile.
However, the company warned humour should be used appropriately as it could be misconstrued and unwelcome in a difficult situation.
Julia Porter-Robinson, human resources senior recruitment manager at T-Mobile, said most people welcome enthusiasm and an injection of energy.
"But humour at the expense of another is an example of when it goes wrong and demotivates people," she added.
A survey commissioned by the company revealed if the spirits in a company need lifting workers would like someone with Davina McCall’s enthusiasm.
It also showed employees do not feel motivated by colleagues who make flippant comments and spend their day joking around.