A biomechanical and biological investigation of the impact of cheerleading training on enhancing the physical fitness and musculoskeletal health of girls

Background: Girls’ physical health significantly influences their growth, development, and learning capabilities. The biomechanical effects of physical training, such as cheerleading, are increasingly recognized for their role in optimizing musculoskeletal health and functional performance. This study investigates how cheerleading training impacts junior high school girls' physical fitness, with a specific focus on its biomechanical effects on body composition, bone density, and muscle explosiveness. Biomechanical factors such as force generation, joint stability, and bone strength are integral to understanding how physical activities like cheerleading influence the body. Methods: Eighty normal junior high school girls with no prior training experience, sixty cheerleaders, and sixty aerobics athletes constituted the study’s control and experimental groups. Participants were randomly assigned to either the training group or the control group after three to six months of structured, intense training. Key parameters such as height, body mass, BMI, bone density, muscular explosiveness, and percentages of protein, muscle, fat, and inorganic salts were assessed using exercise biology measurements. Biomechanical evaluations were conducted to assess lower and upper limb force production, lumbar and spinal stability, and joint impact resistance using standardized tests. Results: The study revealed significant improvements in body composition among the cheerleading and aerobics groups, including lower fat percentages (P < 0.05) and higher protein, muscle, and inorganic salt percentages. Biomechanically, cheerleading training enhanced the muscular explosiveness of the lower limbs (P < 0.05), demonstrating increased peak power output and improved reaction forces during jumping and landing activities. Conversely, aerobics training led to significant improvements in the muscular explosiveness of the upper and lower limbs, lumbar, abdominal, and low back muscles (P < 0.01), indicating greater overall functional strength and dynamic stability. Bone mineral density (BMD) tests showed that the hip and spine BMD of the cheerleading and aerobics groups were significantly higher than those of the control group (P < 0.05), suggesting enhanced bone remodeling and mechanical loading benefits. The aerobics group exhibited superior BMD gains compared to the cheerleading group, particularly in load-bearing areas, indicating higher adaptive responses to varied mechanical stresses. Conclusion: This study provides strong evidence that cheerleading training positively impacts junior high school girls’ physical fitness, particularly in biomechanical aspects such as body composition, bone density, and muscle explosiveness. The findings highlight the specific biomechanical adaptations induced by cheerleading, such as increased force generation in lower limbs, improved joint loading mechanics, and enhanced bone strength.