The effect of emotional intelligence and emotional regulation in elite military units

Bird, Anthony Stephen (2025) The effect of emotional intelligence and emotional regulation in elite military units. PhD thesis, University of Glasgow.

Abstract

Despite widespread application of emotional intelligence (EI) assessments in high-stakes occupations, fundamental theoretical and methodological challenges persist regarding how well current measurements represent the nomological network of EI and their predictive validity. The extent to which existing EI instruments capture a unified construct versus distinct psychological phenomena, remains unclear. Simultaneously, while emotional regulation (ER) theory demonstrates clear links to performance under stress, there remains a critical absence of empirically validated intra-personal regulation interventions that can be effectively deployed in real-world, high-pressure contexts. This thesis addresses these substantial theoretical and practical limitations through two complementary studies investigating EI measurement precision and ER intervention efficacy within British Royal Marine Commandos training.

Study 1 examined how well current EI measurements represent the construct by investigating convergent validity between two leading ability-based assessments, the MSCEIT and GECo, and their predictive utility for military training success. Analysis revealed weak to moderate correlations between total EI scores, with similarly labelled sub-scales showing negligible correlations, indicating low convergent validity and suggesting these instruments capture different aspects of EI’s nomological network. Comparative analysis demonstrated that Officer recruits possessed significantly higher EI across most domains compared to civilian reference samples, while non-Officer recruits showed mixed profiles. Logistic regression identified only the GECo emotional management sub-scale as predictive of Officer training success, while the MSCEIT showed no predictive utility in either cohort, and no EI measures predicted non-Officer outcomes.

Study 2 evaluated a novel three-component ER intervention (The King Strategy®1) combining resonance breathing, cognitive reframing, and vagus nerve reset techniques through a longitudinal experimental design (n=233). Mixed-effects modelling revealed significant improvements in Commando training performance markers for intervention participants. Under acute stress serials, critical findings included enhanced memory recall when ER strategies were actively employed, with optimal heart rate recovery occurring within 99 seconds; beyond this threshold, memory performance declined significantly. Longitudinally, the intervention increased heart rate variability (RMSSD), reduced perceived stress, enhanced interoceptive awareness, and improved EI sub-scales (management, understanding, regulation) while leaving emotional recognition unchanged.

These findings contribute to EI theory by demonstrating measurement challenges within the construct’s nomological network while establishing utility for role-specific applications. The study advances ER theory by providing empirical validation of a multi-modal intra-personal regulation strategy and identifying critical physiological thresholds for cognitive performance under stress. Practically, this research informs evidence-based selection processes and provides a deployable intervention for enhancing human performance in high-stakes environments.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Subjects: B Philosophy. Psychology. Religion > BF Psychology; H Social Sciences > HD Industries. Land use. Labor > HD28 Management. Industrial Management
• Colleges/Schools: College of Social Sciences > Adam Smith Business School > Management
• Supervisor's Name: Searle, Professor Rosalind and Offord, Dr. Matt
• Date of Award: 2025
• Depositing User: Theses Team
• Unique ID: glathesis:2025-85373
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 06 Aug 2025 08:13
• Last Modified: 16 Oct 2025 16:25
• Thesis DOI: 10.5525/gla.thesis.85373
• URI: https://theses.gla.ac.uk/id/eprint/85373