A new study published in Psychological Science indicates that differences in physical attributes may help to explain observed sex differences in certain personality traits. The findings suggest that men might be less anxious than women on average in part because they tend to be physically stronger.
Research has consistently found that women tend to score higher than men on measures of neuroticism, a personality trait characterized by anxiety, depression, and emotional instability. But the underlying mechanisms behind this sex difference in personality remains unclear.
“I’ve always wondered about whether some of the average differences in personality that we see between men and women may not just be down to gender per se, but rather can be explained by some of the of the physical attributes that are more common in men and women,” said study author Nicholas Kerry, a PhD candidate at Tulane University.
“I thought that a great place to start would be physical strength since this is something where we know that there is a fairly large average sex difference.”
In two studies, which examined 854 undergraduate students, the researchers found that physical strength was negatively related to anxiety. In other words, physically stronger people tended to score lower on a measure of anxiety. In line with previous research, women tended to report more anxiety than men and physical strength was found to partially account for this sex difference.
“I think one big takeaway is that our abilities and physical attributes may shape our personalities and the way that we behave and interact with people,” Kerry told PsyPost.
The participants squeezed handheld dynamometers to objectively test their grip strength and provided ratings of their self-assessed physical strength and fighting ability. They also completed the Big Five Inventory, a common measure of personality traits.
The researchers controlled for body mass index, age, self-perceived attractiveness, and other personality traits. But like all research, the study includes some limitations.
“This research is correlational, so we can’t say for sure if the relationship between strength and anxiety is the result of people adjusting their behavior or personality to suit their physical attributes, or whether there is some underlying factor (e.g. genetic or hormonal) that leads to greater physical strength and also reduces anxiety,” Kerry said.
The study, “Physical Strength Partly Explains Sex Differences in Trait Anxiety in Young Americans“, was authored by Nicholas Kerry and Damian R. Murray.