PTSD can happen to an individual after experiencing or witnessing a traumatic event and can last for months or years. But there is a lot that is still not understood about this mental health condition.

Anthropologists, social scientists and veterans from Arizona State University and the Naval Postgraduate School are the first to analyze the relationship between the hormones cortisol and testosterone and PTSD in a non-industrialized society.

This new study sheds more light on the PTSD puzzle.

Homing in on hormones

Previous studies about PTSD and hormones have focused only on people living in Western or European industrialized societies. They included people who suffered from different types of trauma like car crashes, assault and multiple deployments, according to Ben Trumble, a research scientist at the Institute of Human Origins and associate professor at the School of Human Evolution and Social Change.

The studies showed the majority of people diagnosed with PTSD had very little change in their cortisol levels throughout the day. Instead, the results showed "blunted" levels of cortisol and not the normal rise and fall patterns.

"In healthy men, hormones like testosterone and cortisol follow a pattern throughout the day," Trumble said. "Hormone levels are the highest just after waking up, and then decline rapidly. Levels are low throughout the day, and rise again at night."

The big question Trumble and colleagues wanted to answer was, would they see this same pattern in a non-industrialized population with people who suffered from the same type of trauma?

"Our study is the first to examine associations between hormones (cortisol and testosterone) among the Turkana," Trumble said. "Turkana pastoralists experience a high degree of combat exposure, and 28% of men have symptoms of PTSD. Because nearly everyone gets exposed to combat, we can see if there are biological differences in hormones for those with PTSD and those without PTSD. So, in this case we can compare apples to apples and not apples to oranges."

What the ASU scientists found was surprising.

"We did not find any difference in cortisol for Turkana warriors with a provisional PTSD diagnosis versus those without PTSD," said Michael Baumgarten, an Institute of Human Origins-affiliated graduate student and Army Ranger veteran. "Both groups of warriors had nearly identical cortisol patterns. Interestingly, Turkana men with PTSD had lower testosterone when they woke up compared to those without PTSD."

"A more applied takeaway is to look at the results of this study and either retain or increase the level of skepticism one has of narratives that claim to have a crystal-clear picture of how human physiology responds to the stresses of combat -- especially if they are trying to sell you something," he said.

Why the Turkana?

Being a livestock farmer, or pastoralist, in Kenya near South Sudan can be dangerous and deadly.

The Turkana are mobile pastoralists and engage in cattle raiding, said Matthew Zefferman, an assistant professor at the Naval Postgraduate School and U.S. Air Force veteran.

Zefferman spent half a year in the field with the Turkana during his postdoctoral fellowship at ASU.

"The Turkana in our study area, who raid other pastoralists, typically do so across the disputed border with South Sudan," he said. "They travel by foot, often over 60 miles and engage in small and large raids. They are also raided by members of other pastoral groups. These raids can result in firefights and the death of family members, and the loss of animals. About half of adult male deaths in the study area is due to raiding."

Turkana warriors experience similar trauma from combat exposure during cattle raids. They also share similar cultural backgrounds and are the same gender. This differs from previous studies conducted where trauma and cultural background are different.

"It is interesting to see how the physiological response to trauma exposure can differ based on cultural environment," said Sarah Mathew, a research scientist at the Institute of Human Origins and associate professor at the School of Human Evolution and Social Change. "It suggests that we can't answer basic questions about human biology by only studying industrialized populations."

Mathew's relationship with the Turkana since 2007 led to this project and many others, providing valuable information about non-industrialized cooperation, cultural norms and warfare.

While the study answers questions about hormonal regulation, there is still the question of why are the Turkana cortisol levels "normal" in those diagnosed with PTSD compared with Western populations?

The study sites many possible reasons including physical activity and cultural differences. The scientists say more research is needed.

A previous publication by Zefferman and Mathew stated that unlike soldiers of nation-state societies, "Turkana warriors are strongly endorsed by the whole community, have elevated status, perform culturally sanctioned rituals after raids, and are deeply integrated with their corresponding civilian community.

"These longstanding cultural traditions of warriorhood may buffer them from some of the negative physiological responses to combat trauma."

Mathew and the others emphasize the importance of sharing their findings with the Turkana. The researchers have engaged with the community over several years, and discuss findings from this and other ongoing studies and what these findings mean for future research.

"We can only do this research because of the support and help of the people we do the research with -- the Turkana," Zefferman said. "We acknowledge that their willingness to work with us is what has allowed us to do this research with potential benefits to our society.

"We go there at the grace of the people we work with."

Retirees who play pickleball can build a strong new sense of self, but simply spending hours on the court is not enough to forge this post-retirement identity. Instead, developing skills and feeling deeply invested in the sport are the actual drivers of a new leisure-based identity. These findings were recently published in the Journal of Aging and Physical Activity.

Leaving the workforce often triggers a major life transition. Many people build their self-image around their careers over decades of employment. When that professional role vanishes upon retirement, older adults can experience an identity crisis. According to foundational psychological theories, an identity crisis occurs when there is a mismatch between how people view themselves and what society expects of them.

Failing to resolve this gap can lead to feelings of confusion, dissatisfaction, and depression. Researchers wanted to understand how older adults might reconstruct their sense of self through new activities. Sports and hobbies offer a potential avenue for retirees to establish a new framework for who they are.

The academic field of recreation studies refers to this as serious leisure. Serious leisure involves pursuing an amateur activity with enough dedication that participants develop specialized skills, knowledge, and experience. Over time, participants can develop a leisure identity, where they view themselves and are viewed by others as a dedicated member of a specific community.

Pickleball has surged in popularity over the last decade, especially among older demographics. A 2023 report from the Sports and Fitness Industry Association noted that over 13 million people in the United States played the sport. The game combines elements of tennis, badminton, and ping-pong. Because it is highly social and accommodates various physical mobility levels, it attracts older adults looking for both exercise and camaraderie.

A research team led by Chungsup Lee of California State University Long Beach and Amy Chan Hyung Kim of Florida State University set out to test how pickleball habits relate to identity. They suspected that active participation would help retirees view themselves primarily as pickleball players. They also wanted to know if self-reported skill levels and mental investment mediated this psychological shift.

The researchers recruited 188 retired adults at the 2019 Minto US Open Pickleball Championships in Naples, Florida. The tournament is one of the largest in the country, drawing thousands of competitors and spectators. The participants in the study were at least 50 years old, with an average age of about 67. The vast majority of the respondents identified as white, and over seventy percent held a college degree.

To understand the players’ habits, the researchers asked the participants a series of questions about their time on the court. They recorded how many hours and how many days per week each person played the sport. The participants also self-reported their skill levels using a standard rating system ranging from beginner to top-caliber player. The average skill rating in the group was slightly above the intermediate level.

The survey then measured psychological involvement across three specific categories. The first category, attraction, measured how much participants enjoyed the sport. The second category, centrality, assessed how much the participants prioritized pickleball in their daily lives. The third category, social bonding, evaluated how strongly the participants’ friendships and social ties revolved around the game.

Finally, the researchers measured leisure identity using a modified athletic identity scale. This involved asking participants if they considered themselves to be pickleball players and if they felt other people viewed them that way. The identity scale also assessed whether participants tied their personal self-worth to their performance, feeling happy when they played well and bad about themselves if they performed poorly.

The researchers analyzed the survey data using a statistical technique designed to uncover indirect relationships between variables. This allowed the team to see whether simply playing the game directly predicted a person’s identity. They could also test if the relationship depended on intermediate steps like skill building and emotional investment.

The statistical models revealed that playing pickleball frequently was positively associated with having a higher skill rating. Playing often was also linked to higher psychological involvement. This means that individuals who spent more time on the court tended to feel more attached to the sport and the community surrounding it.

However, the results showed that just showing up to play did not directly foster a new leisure identity. The sheer volume of hours spent playing the game had no direct link to a person’s sense of self. A retiree could play several times a week without necessarily internalizing the identity of a dedicated pickleball player.

Instead, the relationship relied entirely on intermediary factors. Developing a higher skill rating was associated with a stronger leisure identity. A higher skill rating also linked to stronger psychological involvement. As players improved their game, they often became more mentally and socially invested in the sport.

Psychological involvement had the strongest direct association with leisure identity. The social and emotional bonds formed around the sport were the main bridge between playing the game and adopting it as a core part of one’s identity. In other words, participation only translated into a new identity if the player improved their skills or became deeply embedded in the sport’s community and culture.

The study relied on survey data collected at a single point in time, which presents a limitation. Because the researchers did not track participants over several years, the results cannot prove that playing pickleball causes a change in identity. It is highly possible that people who already possess a strong leisure identity choose to play more frequently and invest more heavily in their skills.

The participant pool also restricts how the results can be interpreted. The researchers recruited players at a major national tournament. These individuals likely exhibit much higher dedication and skill than casual players who occasionally drop by a local community center. This selection bias means the findings might mostly reflect the mindset of highly competitive older adults.

Future studies will need to follow diverse groups of casual and dedicated players over time to see exactly how identity evolves after retirement. Researchers might also explore how engaging in multiple different hobbies at once shapes a person’s overall self-image. Exploring ways to foster social bonds and skill development in local recreation programs could assist older adults navigating the transition out of the workforce.

Public recreation departments and senior centers could use these insights to design better programs. Simply providing open court time might not be enough to help retirees build a supportive new identity. Offering formal skill clinics and hosting social events around the sport could help older adults cultivate the psychological involvement necessary for a fulfilling post-retirement life.

The study, Pickleball Participation and Leisure Identity Among Retirees: The Mediating Role of Skill Ratings and Psychological Involvement, was authored by Chungsup Lee, Amy Chan Hyung Kim, Jungsu Ryu, Sua Im, Jinmoo Heo, Hyunmin Yang, and Soyoung Lee.