PURPOSE: The aim of this study was to evaluate the efficacy of a 17-week, 3-component lifestyle intervention for enhancing health behaviors during the coronavirus disease-2019 (COVID-19) pandemic. METHODS: A parallel-group (intervention and control) study was conducted amongst 79 airline pilots over a 17-week period during the COVID-19 pandemic. The intervention group (n = 38) received a personalized sleep, dietary, and physical activity (PA) program. The control group (n = 41) received no intervention. Outcome measures for sleep, fruit and vegetable intake, PA, and subjective health were measured though an online survey before and after the 17-week period. The changes in outcome measures were used to determine the efficacy of the intervention. RESULTS: Significant main effects for Time × Group were found for International Physical Activity Questionnaire-Walk (p = 0.02) and for all other outcome measures (p < 0.01). The intervention group significantly improved in sleep duration (p < 0.01; d = 1.02), Pittsburgh Sleep Quality Index score (p < 0.01; d = -1.01), moderate-to-vigorous PA (p < 0.01; d = 1.32), fruit and vegetable intake (p < 0.01; d = 3.11), Short-Form-12v2 physical score (p < 0.01; d = 1.84), and Short-Form-12v2 mental score (p < 0.01; d = 2.69). The control group showed significant negative change for sleep duration (p < 0.01; d = -0.47), Pittsburgh Sleep Quality Index score (p < 0.01; d = 0.28), and Short-Form-12v2 mental score (p < 0.01; d = -0.64). CONCLUSION: Results provide preliminary evidence that a 3-component healthy sleep, eating and PA intervention elicit improvements in health behaviors and perceived subjective health in pilots and may improve quality of life during an unprecedented global pandemic.