The director of the Laboratory for Therapeutic Sciences at the University of Hawai'i at Hilo is investigating the stress levels and physiology of student-athletes during their long trips east of Hawai'i for away games.
Linc Gotshalk, a professor of Kinesiology & Exercise Sciences, is heading the study. Gotshalk is a musculoskeletal physiologist, anatomist and exercise physiologist with a strong background in muscular strength and power training and total body systemic response to exercise and stress. In 2023, he received the UH Board of Regents' Award for Excellence in Teaching.
In this study of Hawai'i Hilo student-athletes who repetitively fly east for games, Gotshalk is investigating the way stress hormones affect the athletes' bodies and brains. The main hormone in question in the study is cortisol, which increases as humans are exposed to stressors. Student research assistants are analyzing the data.
"What we're studying is stress physiology, which includes huge amounts of hormonal changes due to stress," explained Gotshalk. "Stress in the short term is a needed thing in life, so you can run from the tiger, so you can fight a war — whatever it be. [But] psychogenic stress, where you're not actually using energy, can pump stuff into the system that's meant to be used. That, then, repeatedly ends up being a problem because stuff gets put in inappropriate places after a while."
Part of the study is assessing the physiological effect of stress on sub-muscular fat distribution, which can be strongly affected by chronic exposure to excess amounts of cortisol. Over time, lots of unused cortisol in the system can lead to excess submuscular and abdominal adipose tissue, also known as "android fat."
"It's part of the problem with things like type 2 diabetes," said Gotshalk.
But what makes student-athletes the perfect population for a stress study? "We're on an island," Gotshalk explained. "That means that athletics teams who do not have home games here on the island, but all away games, they have to fly, and flight can be a perturbation, which means it can be a stress factor." Two notable stressors are changes in cabin pressure in flight and changes in time zones.
The main hormones Gotshalk and his research team are studying are the stress hormones, which includes cortisol. He said cortisol is the alarm clock. It wakes you up in the morning. A lot of the other hormones rise at night, when the body is preparing for repair. But flying east frequently raises stress levels in the body at inopportune times due to the effect on chronobiology and the circadian rhythm.
"Essentially, excess cortisol is like having one's internal alarm clock go off at random times throughout the day, a phenomenon which is made worse by flying somewhere with a time difference. Due to this measurably higher amount of stress, including the stress of then having to play a sport in an unfamiliar environment, student-athletes are the perfect population in which to study the effects of cortisol on the body."
Student researchers at UH Hilo compared data collected from female athletes on the campus's volleyball team.
A student investigator involved with that study said, "My peers and I got hands-on experience of cortisol testing with the UH women's volleyball team. We did anthropometric measurements and took saliva samples pre and post season on the volleyball team to see if there was a correlation between stress and traveling east."
Gotshalk said the research team found "a correlation between cortisol rise and anthropometric changes and biometric changes." This correlation, although not yet conclusive, points to the validity of Gotshalk's hypothesis about stress and away game travel.
The results of the study are to be published in the near future.
