Imagine a sports coach observing his or her team from the sidelines during an important game. Are images of super-tense faces, frantic to-and-fros and stressed-out body language coming to mind? New research shows that’s the worst thing they can do for their team.

Seeking to examine the impact of coaches’ emotions on the groups they train, researchers from the University of Haifa and University of Amsterdam wanted to find out how their anger or happiness influences the players’ emotions and performance during the game.

The results, recently published in Psychology of Sport and Exercise, show that the coaches do have an effect.

“The coaches’ emotions have a crucial influence on the team’s performances. Expressions of happiness directed at the players before the game begins will increase the chances of leading at half-time, independently of differences in the league standings of the two teams,” explained Arik Cheshin from the University of Haifa, one of the study’s authors.

“Alongside all the professional and tactical demands, coaches need to know that their emotions also influence the team’s performance, for better or for worse,” he added.

The research was comprised of two sub-studies carried out in amateur leagues. The first was conducted among 30 baseball and softball teams, in which 268 players were asked to complete a questionnaire after the end of the game.

The second study was conducted among 30 soccer teams, with 376 players filling out questionnaires before the game began, at half-time and after the game ended. The first two sets of questionnaires were filled out after the coaches’ pep talks.

Another interesting finding was that players felt happy when the coaches expressed happiness, and angry when the coaches conveyed anger – regardless of their performances in the game.

“The coaches’ emotions infect the players, provide them with information, and ultimately influence their performances. The coaches’ emotions can make the difference between winning and losing the game,” Cheshin concluded.