More specifically, they asked them to complete a personality questionnaire that included assessments such as, “I make contact easily when I meet people,” and “I often feel unhappy.”

They also had the athletes rate their most stressful recent moment during sports, using a spectrum from a low level of stress to extremely stressful.

Finally, for a separate portion of the experiment, the researchers asked 32 additional male college athletes to fill out the personality assessment as well as another questionnaire that delved into their current confidence and stress levels.

They then ran the men through a complicated, unfamiliar athletic drill, involving kicking balls and sprinting while being pressured and observed. Afterward, the men filled out a final questionnaire about how they had felt during the training.

Crunching the resulting data, the researchers found that 140 of the athletes in the first group qualified as Type D. These athletes were far more likely than the others to rate a relatively minor incident, such as a coach being sick and missing a game, as extremely stressful.

Similarly, almost a third of the athletes in the second group qualified as Type D and reported greater anxiety and less self-confidence before the drill than the others. They also were slower and slightly more inept during the routine and, afterward, signified on the questionnaire that they felt resigned about not having done well and did not wish to think about their errors.

This reaction, which the researchers designate as “resignation/withdrawal” is probably not the most effective response to sports training, says Erika Borkoles, a lecturer at Queensland University of Technology, who led the experiments.