Angle Specificity of the Knee Extensor Age-Related Profile in Young Female Athletes

Abstract

The angle specificity of the knee extensor age-related profile was examined in young females (13 - 19 yr). Twenty-one track & field jumpers, 20 volleyball players and 20 non-active females were separated into the youngest and the oldest age categories, based on the official competitive age categories. The maximum knee extensor isometric torque (T_MAX) was measured at 9 knee angles. The relationships between T_MAX at the peak of the torque-angle curve and at the other knee angles (angle-angle relationships) were expressed by R² (%). Statistics included two-way ANOVA for age category differences and curve fitting to R² joint angle trend lines. Differences between age categories were significant for the volleyball players and the non-active females (p < 0.05). Age category had an angle specific impact on angle-angle relationships in the athletes, with the youngest ones demonstrating greater R² decrease at the more extended, or more flexed, knee angles. Significant quadratic R² joint angle trend lines were found in all track & field jumpers (p < 0.05) and, in the youngest only volleyball players (p < 0.05), but not in the non-active females (p > 0.05). In conclusion, the knee extensor profiles of young female athletes show an age-related angle specificity that should be accounted for when treating athletes within the age range examined.

adolescent - isometric - correlations - injury - track and field jumpers - volleyball players

References

• 1 Aagaard P. Training-induced changes in neural function.  Exerc Sport Sc Rev. 2003;  312 61-67
• 2 Anderson A F, Dome D C, Gautam S, Awh M H, Rennirt G W. Correlation of anthropometric measurements, strength, anterior cruciate ligament size, and intercondylar notch characteristics to sex differences in anterior cruciate ligament tear rates.  Am J Sports Med. 2001;  29 58-66
• 3 ASEP (American Sport Education Program) .Coaching Youth Volleyball. 3rd edn. Champaign, IL, USA; Human Kinetics Inc 2001
• 4 Barak Y, Ayalon M, Dvir Z. Transferability of strength gains from limited to full range of motion.  Med Sci Sports Exerc. 2004;  36 1413-1420
• 5 Beynnon B D, Fleming B C. Anterior cruciate ligament strain in-vivo: a review of previous work.  J Biomech. 1998;  31 519-525
• 6 Demorest R A, Landry G L. Training issues in elite young athletes.  Curr Sports Med Rep. 2004;  3 167-172
• 7 Dugan S A. Sports-related knee injuries in female athletes: What gives?.  Am J Phys Med Rehabil. 2005;  84 122-130
• 8 Emery C A. Risk factors for injury in child and adolescent sport: a systematic review of the literature.  Clin J Sport Med. 2003;  13 256-268
• 9 Graham-Smith P, Lees A A. Three-dimensional kinematic analysis of the long jump take-off.  J Sports Sci. 2005;  23 891-903
• 10 Ikeda H, Kurosawa H, Kim S G. Quadriceps torque curve pattern in patients with anterior cruciate ligament injury.  Int Orthop. 2002;  26 374-376
• 11 Keays S L, Bullock-Saxton J, Keays A C. Strength and function before and after anterior cruciate ligament reconstruction.  Clin Orthop Relat Res. 2000;  73 174-183
• 12 Kraemer W J, Newton R U. Training for muscular power.  Phys Med Rehabil Clin N Am. 2000;  11 341-368
• 13 Marcora S, Miller M K. The effect of knee angle on the external validity of isometric measures of lower body neuromuscular performance.  J Sports Sci. 2000;  18 313-319
• 14 Murphy A J, Wilson G J, Pryor J F, Newton R U. Isometric assessment of muscular function: The effect of joint angle.  J Appl Biomech. 1995;  11 205-215
• 15 Myer G D, Ford K R, Hewett T E. Rationale and clinical techniques for anterior cruciate ligament injury prevention among female athletes.  J Athl Training. 2004;  39 352-364
• 16 Nemoto I, Kanehisa H, Miyashita M. The effect of sports training on the age-related changes of body composition and isokinetic peak torque in knee extensors of junior speed athletes.  J Sports Med Phys Fitness. 1990;  30 83-88
• 17 Perttunen J, Kyrolainen H, Komi P V, Heinonen A. Biomechanical loading in the triple jump.  J Sports Sci. 2000;  18 363-370
• 18 Shirakura K, Kato K, Udagawa E. Characteristics of the isokinetic performance of patients with injured cruciate ligaments.  Am J Sports Med. 1992;  20 754-760
• 19 Tanner J M, Whitehouse R H, Cameron N, Marshall W A, Healy M JR, Goldstein H. Assessment of Skeletal Maturity and Prediction of Adult Height TW2 Method. London, UK; Academic Press, Ltd. 1983
• 20 Tokuyama M, Ohashi H, Iwamoto H, Takaoka K, Okubo M. Individuality and reproducibility in high-speed motion of volleyball spike jumps by phase-matching and averaging.  J Biomech. 2005;  38 2050-2057
• 21 Urabe Y, Kobayashi R, Sumida S, Tanaka K, Yoshida N, Nishiwaki G A, Tsutsumi E, Ochi M. Electromyographic analysis of the knee during jump landing in male and female athletes.  The Knee. 2005;  12 129-134
• 22 van Praagh E, Dore E. Short-term muscle power during growth and maturation.  Sports Med. 2002;  32 701-728