Impact of Exam Stress and Time of Day on Hand Grip Fatigue in Medical Students

Abstract Medical schools are using summative examinations to evaluate the students’ knowledge and competencies acquired in various biomedical and clinical domains throughout medical education. These examinations are necessary, but they are known to evoke high levels of stress in the students involved. Previous studies have shown that increased stress levels can negatively impact participants' cognitive and physical abilities, resulting in a decrease in overall performance. Our study was designed to test this relationship by comparing student hand grip strength output and fatigue rates using grip strength on stressful (exam) and non-stressful (non-exam) days.First-year medical students were recruited to squeeze a hand dynamometer at maximum muscle tension for 30 seconds three separate times. Students gave these readings on four separate days, including: morning examination/non-examination and afternoon examination/non-examination. Data sets were completed using a Vernier Go Direct Hand Dynamometer and Vernier Graphical Analysis Pro program. Statistical analysis was initially completed using GraphPad Prism, where the slope, the area under the curve (AUC), maximum, and average force were initially analyzed. The experimental data were further analyzed using analysis of variance (ANOVA), fitted with simple regression lines for the slope of fatigue for each pair of conditions, and a mixed linear model was created and tested using R statistical software.A total of 207 recorded hand grip profiles from 21 students were collected; 12 students completed the entire study (provided all measurements consisting of four days of 3 data sets each). These results showed no statistical significance when examining the maximum or average peak force and the area under the curve of the grip profiles. The analysis using simple regression in GraphPad Prism for fatigue (or force rundown) revealed a statistically significant effect in the morning data sets only, where, on exam days, fatigue was accelerated (slopes differed, p = 0.0013).The main statistically significant finding was an accelerated rate of hand grip fatigue in the morning but not on the afternoon exam days, suggesting that exams might be less stressful in the afternoon. Scheduling stressful exams in the afternoons might not affect muscle hand grip as much as exams in the morning and might correlate with better student academic outcomes.