Once more unto the breach! A pep talk, if done well, can inspire an army into battle. Go get ’em also works in less dramatic circumstances. Research by Professor Tiffanye Vargas at California State University shows that, across sports, coaches’ pre-game speeches matter: 90% of players enjoy listening, and 65% say pep talks affect the way they play. Business leaders, too, have focused on how to best motivate their employees.

According to research by husband-and-wife team Jacqueline and Milton Mayfield, a good pep talk includes clear directions, empathetic language and an explanation of why a task is important to you and the wider community. Depending on the audience, the weighting of each element can vary. For example, if you’re encouraging a friend, you might not need to establis...