When perceived as threatening, social interactions have been shown to trigger the sympathoadrenal medullary system as well as the hypothalamic-pituitary-adrenal axis resulting in a physiologic stress response. The allostatic load placed on human health and physiology in the context of acute and chronic stress can have profound health consequences. The purpose of this study was to develop a protocol for a lab-based stress stimulus using social-evaluative threat. While several valid, stress-stimulating protocols exist, we sought to develop one that triggered a physiologic response, did not require significant lab resources, and could be completed in around 10 min. We included 53 participants (29 men and 24 women) and exposed them to a modified version of the Stroop Color-Word Interference Task during which the participants were made to feel they were performing the task poorly while the lead researcher feigned annoyance and frustration. After exposure to this Feigned Annoyance and Frustration (FAF) Test, both the men and women in this study demonstrated a statistically significant and clinically meaningful increase in subjective stress on the visual analog scale. Additionally, the men in this study demonstrated a statistically significant increase in heart rate and salivary α-amylase concentrations after exposure to the test. The women in this study did not demonstrate a statistically significant increase in the physiologic stress biomarkers. This protocol for the FAF Test shows promise to researchers with limited time and resources who are interested in experimentally activating the sympathoadrenal medullary system.

Background The relationship between exercise and lifespan is well documented, but little is known about the effects of specific exercise protocols on modern measures of biological age. Transcriptomic age predictors provide an opportunity to test the effects of high intensity interval training (HIIT) on biological age utilizing whole-genome expression data. Methods A single-site, single-blinded, randomized controlled clinical trial design was utilized. Thirty sedentary participants (aged 40 to 65) were assigned to either a HIIT group or a no-exercise control group. After collecting baseline measures, HIIT participants performed three 10×1 HIIT sessions per week for 4 weeks. Each session lasted 23 minutes, and total exercise duration was 276 minutes over the course of the 1-month exercise protocol. Transcriptomic age, PSS-10 score, PSQI score, PHQ-9 score, and various measures of body composition were all measured at baseline and again following the conclusion of exercise/control protocols. Results Transcriptomic age reduction of 3.59 years was observed in the exercise group while a 3.28-year increase was observed in the control group. PHQ-9, PSQI, BMI, body fat mass, and visceral fat measures were all improved in the exercise group. A hypothesis-generation gene expression analysis suggested exercise may modify autophagy, mTOR, AMPK, IP3K, neurotrophin signaling, insulin signaling, and other age-related pathways. Conclusion A low dose of HIIT can reduce an RNA-based measure of biological age in sedentary males and females between the ages of 40 and 65. Other changes to gene expression were relatively modest, which may indicate a focal effect of exercise on age-related biological processes.

There is a well-established connection between psychosocial stress and low back pain, however studies demonstrating a connection between motor control and acute stress are lacking. What is the potential interaction of acute stress (the Feigned Annoyance and Frustration Test, or the FAF Test) with lower quarter motor control and stance stability during a standing lower-extremity dexterity task in individuals with and without low back pain? This prospective cohort study included 30 individuals with low back pain (15 men and 15 women) with an equal number of sex-matched controls for a total sample of 60 participants. Participants were fitted with surface electromyography sensors over the trunk and lower extremities. The lower extremity dexterity task was performed on 2 in-ground force plates while center of pressure data was collected. Participants were exposed to the FAF Test and the lower extremity dexterity task was repeated. Stress resulted in decreased muscle activation for muscles of the trunk and gluteals, as well as decreased total excursion and velocity of the center of pressure. Acute stress appears to alter trunk control during a standing lower extremity dexterity task, with more pronounced changes apparent in participants with low back pain. These findings provide novel insight into the influence of stress on trunk control and balance stability.