Effects of Strength Training on Body Composition, Physical Fitness, and Quality of Life in Older Adults with Treatment Naïve Chronic Lymphocytic Leukemia

Abstract

Chronic Lymphocytic Leukemia (CLL) is the most prevalent leukemia among adults in Western countries, with patients often experiencing compromised physical fitness, immune dysfunction, and reduced health-related quality of life (HRQOL). Despite growing interest in exercise as an adjunct therapy, research on structured physical activity interventions in CLL remains limited. This dissertation aggregates findings from five studies exploring the effects of physical exercise on CLL patients, focusing on physical fitness, immune markers, and HRQOL outcomes. A systematic review (study 1) assessed the impact of exercise on CLL patients, identifying six studies (n=323) that primarily investigated cardiovascular and resistance training interventions. The findings underscored significant improvements in physical fitness and immune parameters, though variability in study designs limited conclusive recommendations, and identified the strengthbased resistance training understudied gap among literature. The ADRENALINE pilot study (study 2) further explored baseline activity levels, functional capacity, and immune markers in treatment-naïve CLL patients, revealing suboptimal cardiovascular fitness and a high prevalence of sedentary behavior despite selfreported functional competence. Notably, moderate-to-vigorous physical activity correlated positively with muscle strength and lean mass, suggesting a potential role for targeted exercise interventions in mitigating disease-related deterioration. To address the need for structured interventions, study 3 evaluated the effects of a 16-week individualized strength-based resistance training program on HRQOL in CLL patients. Results demonstrated significant improvements in functional well being and physical functioning, with promising trends in overall quality of life. Similarly, study 4 and 5 examined the feasibility and efficacy of a strength-based resistance training protocol, reporting large effect sizes for muscle strength gains and reductions in body fat percentage and neutrophil count, indicating potential immunomodulatory benefits. Together, these studies highlight the feasibility and potential benefits of structured exercise interventions in CLL patients, particularly with a strength based resistance training approach. Findings emphasize the need for larger, long-term trials to establish evidence-based exercise guidelines, optimize patient outcomes, and explore mechanistic links between physical activity and disease progression. This research contributes to the growing body of evidence supporting exercise as an integral component of supportive care in CLL management.