Effect of Strength Training on Jump-Landing Biomechanics in Adolescent Females

Abstract

Background: Sex-based differences in neuromuscular characteristics relevant to anterior cruciate ligament (ACL) injury risk may arise as compensation for divergent strength development during puberty. Strength training during this period may prevent the development of these undesirable neuromuscular characteristics. Hypothesis: Strength-trained middle school girls will have improved jump-landing biomechanics compared with control participants. Study Design: Cohort study. Level of Evidence: Level 3. Methods: Maximum voluntary isometric contraction in hip extension and abduction and knee extension and flexion as well as Landing Error Scoring System (LESS) scores were collected for healthy female middle school students of grades 6 to 8. Strength-training participants (STR: N = 30; height, 1.63 ± 0.07 m; mass, 48.1 ± 7.6 kg; age, 12.5 ± 1.0 y) were matched with control participants (CON: N = 30; height, 1.60 ± 0.09 m; mass, 47.2 ± 8.9 kg; age, 12.6 ± 0.9 y). The training consisted of a 6-month strength-training program administered through a gym class curriculum that targeted the lower extremity. A repeated-measures mixed-model analysis of variance was used for comparisons between groups and across time (α = 0.05). Stepwise linear regression was used to examine the relationship between strength change and LESS score change. Results: Strength values (N·m/kg) increased across time and to a greater degree in STR for hip extension (baseline 3.98 ± 1.15 vs follow-up 4.77 ± 1.80), hip abduction (4.22 ± 1.09 vs 5.13 ± 2.55), and knee flexion (3.27 ± 0.62 vs 3.64 ± 1.40) compared with CON. LESS grades significantly decreased across time in STR (5.58 ± 1.21 vs 4.86 ± 1.44) and were significantly lower than CON (5.98 ± 1.42) at follow-up ( P < 0.001). The change in hip extension and knee extension strength explained 67% of the variance ( P < 0.001) in the LESS change score in the STR group. Conclusion: A school-based strength-training program that focused on hip and knee musculature significantly improved jump-landing biomechanics (as determined by LESS) relevant to ACL injury risk. Further investigation using different strength-training approaches in this age group is warranted. Clinical Relevance: Strength training during adolescence holds promise as an injury prevention program. The use of a school-based approach is novel and may represent a robust opportunity for injury prevention programs, as physical education class is often mandatory in this age group.

Multivariate Training Programs during Physical Education Classes in School Context: Theoretical Considerations and Future Perspectives

“…The effects of gender in children's cognitive and motor development were also reported in the literature [61]. Creating positive learning environments at physical education classes for female students using positive teaching strategies enables understanding the female students' attitudes toward physical activity, sports performance, and participation/retention [59,61,65]. Evidence-based physical activity for school-age children and youth extends to several teaching methods such as strength and skill-based training [66], physical education-based interventions [21,23,52], sports basedtraining programs [2,52], and physical activity-based lifestyle intervention [17,20,21].…”

“…Even more, psychomotricity and motor proficiency plays improve sports-related characteristics game-skilled improvements [52], as well as the competences in other areas of knowledge such as reading-writing and mathematical calculations [8]. The effects of gender in children's cognitive and motor development were also reported in the literature [61]. Creating positive learning environments at physical education classes for female students using positive teaching strategies enables understanding the female students' attitudes toward physical activity, sports performance, and participation/retention [59,61,65].…”

“…The development of physical fitness in a school context during Physical Education classes promotes health through changes in body composition, less susceptibility to diseases, and better physical condition [20]. In this regard, some studies have reported successful intervention programs in the context of physical education classes mainly through the application of strength training programs [15,60,61] In addition to improving motor skills and increasing muscle strength and endurance performance, frequent participation in a strength training program in young people triggers relevant health benefits [15,60,61], enhancing body composition and motor coordination [60]. Furthermore, this type of training [62] also improves mental health and muscle strength, recognized for having a positive association with school performance [63].…”

LESS score and isometric lower limb strength after ACL reconstruction in female handball players

“…Absolute strength and individual muscle group strength is one of the main contributor to knee injury prevention in female athletes [9,[43][44].…”

Análisis de dos métodos de entrenamiento para el desarrollo del salto en porristas juveniles elites (Analysis of Two Training Methods for Jump Development in Elite Young Cheerleaders)

“…La mayoría de los estudios sugieren que, aunque el impacto del entrenamiento de fuerza en los saltos en mujeres adolescentes puede variar, puede tener un efecto positivo cuando se dirige a grupos musculares específicos y se combina con otros métodos de entrenamiento (Herman et al, 2022;Piazza et al, 2014;Rousanoglou et al, 2008;Zdunek, 2020).…”