Background: Roles in high-pressure sectors like the military, elite sports, healthcare, and emergency response require physical and cognitive performance under stress. In these situations, the human body triggers complex molecular responses by regulating gene expression, which can potentially impair performance. Identifying these regulatory clues may be important for predicting an individual’s performance outcomes effectively and optimising workload management and training programs.
Purpose: This study investigates the predictive potential of microRNAs (miRNAs) in a non-invasive biofluid such as saliva. miRNA are small non-coding RNAs approximately 22-23 nucleotides in length and play a key regulatory role in gene expression.
Approach: Four controlled human stress trials were conducted, including heat stress, musculoskeletal exertion, psychosocial stress, and sleep deprivation, involving 22 participants per trial aged 18-45 years. Saliva samples were collected at various time points before and after the induction of stress for miRNA isolation and were subsequently analysed using Next Generation Sequencing (NGS). Additional data on demographics, perceived stress, and performance metrics were also collected.
Results: In the heat stress trial, 43 miRNAs were significantly regulated, effectively distinguishing between individuals who completed or did not complete the trial, with 4 miRNAs were identified as potential early predictors of performance outcomes. The sleep deprivation trial resulted in significant downregulation of 26 miRNAs and upregulation of one miRNA post-stress, indicating distinct miRNA profiles for specific stressors.
Conclusion: Preliminary results suggest miRNA profiling can predict performance under stress, such as heat stress, and is altered during sleep deprivation. Ongoing analysis is aimed at correlating various stress and performance metrics with miRNA data. Key miRNAs identified will undergo further verification through quantitative real-time PCR (qRT-PCR) and validation in future targeted studies.