Sex differences in upper- and lower-limb muscle strength in children and adolescents
a meta-analysis
DOI:
https://doi.org/10.51224/SRXIV.451Keywords:
children, gender, fitness, strength, youthAbstract
On average, adult men are physically stronger than adult women. The magnitude of this difference depends on muscle tested, with larger sex differences observed in upper- than lower-limb muscles. Whether muscle-group-specific sex differences in strength are present in children is unclear. The purpose of the current meta-analysis was to determine whether sex differences in muscle strength in children and adolescents differ between upper- and lower-limb muscles. Data were extracted from studies that included participants aged ≤ 17 years who completed maximal isometric or isokinetic tests of upper-limb (elbow flexors or extensors; multi-joint tests) or lower-limb strength (knee flexors or extensors; ankle dorsiflexors or plantarflexors; multi-joint tests). Participants were partitioned into three age groups (5-10, 11-13, 14-17 years old). The analysis included 299 effects from 33 studies. The total sample was 17,263 (9,269 boys, 7,994 girls). For upper-limb tests aggregated, effect sizes were g = 0.58 (95% confidence intervals (CIs) [0.45, 0.71]) and 2.02 (95% CIs [1.81, 2.23]) for 5-10- and 14-17-year-olds, respectively. For lower-limb tests, effect sizes were g = 0.21 (95% CIs [0.15, 0.27]) and 1.25 (95% CIs [0.99, 1.45]) for 5-10- and 14-17-year-olds, respectively. In 5-10-year-olds, weighted means of girls’ upper- and lower-limb strength relative to boys’ strength were 84.5 ± 8.2% and 94.1 ±7.2%, respectively. In 14-17-year-olds, they were 64.7 ± 6.1% and 76.0 ± 8.6%, respectively. Thus, boys are stronger than girls on average. The sex difference in strength increases markedly with male puberty and is more pronounced in upper- than lower-limb muscles throughout development.
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References
Abramovich, D. R. (1974). Human sexual differentiation--in utero influences. Journal of Obstetrics and Gynaecology of the British Commonwealth, 81(6), 448-453. https://doi.org/10.1111/j.1471-0528.1974.tb00494.x
Andersen, L. B., & Henckel, P. (1987). Maximal voluntary isometric strength in Danish adolescents 16-19 years of age. European Journal of Applied Physiology and Occupational Physiology, 56(1), 83-89. https://doi.org/10.1007/bf00696381
Arfai, K., Pitukcheewanont, P. D., Goran, M. I., Tavare, C. J., Heller, L., & Gilsanz, V. (2002). Bone, muscle, and fat: sex-related differences in prepubertal children. Radiology, 224(2), 338-344. https://doi.org/10.1148/radiol.2242011369
Bäckman, E., & Oberg, B. (1989). Isokinetic muscle torque in the dorsiflexors of the ankle in children 6-15 years of age. Normal values and evaluation of the method. Scandinavian Journal of Rehabilitation Medicine, 21(2), 97-103.
Brown, G. A., O'Connor, M. I., & Parker, M. G. (2024). Comments on Sports Participation and Transgender Youths. JAMA Pediatrics, 178(3), 315. https://doi.org/10.1001/jamapediatrics.2023.5960
Courant, F., Aksglaede, L., Antignac, J. P., Monteau, F., Sorensen, K., Andersson, A. M., Skakkebaek, N. E., Juul, A., & Bizec, B. L. (2010). Assessment of circulating sex steroid levels in prepubertal and pubertal boys and girls by a novel ultrasensitive gas chromatography-tandem mass spectrometry method. Journal of Clinical Endocrinology and Metabolism, 95(1), 82-92. https://doi.org/10.1210/jc.2009-1140
Davies, C. T., White, M. J., & Young, K. (1983). Muscle function in children. European Journal of Applied Physiology and Occupational Physiology, 52(1), 111-114. https://doi.org/10.1007/bf00429036
De Ste Croix, M. B., Armstrong, N., Welsman, J. R., & Sharpe, P. (2002). Longitudinal changes in isokinetic leg strength in 10-14-year-olds. Annals of Human Biology, 29(1), 50-62. https://doi.org/10.1080/03014460110057981
De Ste Croix, M. B. A., Armstrong, N., & Welsman, J. R. (2003). The Reliability of an Isokinetic Knee Muscle Endurance Test in Young Children. Pediatric Exercise Science, 15, 313-323. https://doi.org/10.1123/pes.15.3.313
Detter, F., Nilsson, J., Karlsson, C., Dencker, M., Rosengren, B. E., & Karlsson, M. K. (2014). A 3-year school-based exercise intervention improves muscle strength - a prospective controlled population-based study in 223 children. BMC Musculoskeletal Disorders, 15, 353. https://doi.org/10.1186/1471-2474-15-353
Ducher, G., Daly, R. M., Hill, B., Eser, P., Naughton, G. A., Gravenmaker, K. J., Seibel, M. J., Javaid, A., Telford, R. D., & Bass, S. L. (2009). Relationship between indices of adiposity obtained by peripheral quantitative computed tomography and dual-energy X-ray absorptiometry in pre-pubertal children. Annals of Human Biology, 36(6), 705-716. https://doi.org/10.3109/03014460903055139
El Hage, R. P., Courteix, D., Benhamou, C. L., Jacob, C., & Jaffré, C. (2009). Relative importance of lean and fat mass on bone mineral density in a group of adolescent girls and boys. European Journal of Applied Physiology, 105(5), 759-764. https://doi.org/10.1007/s00421-008-0959-4
Elmlinger, M. W., Kühnel, W., Wormstall, H., & Döller, P. C. (2005). Reference intervals for testosterone, androstenedione and SHBG levels in healthy females and males from birth until old age. Clinical Laboratory, 51(11-12), 625-632.
Falkel, J. (1978). Plantar flexor strength testing using the cybex isokinetic dynamometer. Physical Therapy, 58(7), 847-850. https://doi.org/10.1093/ptj/58.7.847
Fritz, J., Cöster, M. E., Stenevi-Lundgren, S., Nilsson, J., Dencker, M., Rosengren, B. E., & Karlsson, M. K. (2016). A 5-year exercise program in children improves muscle strength without affecting fracture risk. European Journal of Applied Physiology, 116(4), 707-715. https://doi.org/10.1007/s00421-015-3310-x
Fukunaga, T., Funato, K., & Ikegawa, S. (1992). The effects of resistance training on muscle area and strength in prepubescent age. Annals of Physiological Anthropology, 11(3), 357-364. https://doi.org/10.2114/ahs1983.11.357
Fuller, N. J., Fewtrell, M. S., Dewit, O., Elia, M., & Wells, J. C. (2002). Segmental bioelectrical impedance analysis in children aged 8-12 y: 2. The assessment of regional body composition and muscle mass. International Journal of Obesity and Related Metabolic Disorders, 26(5), 692-700. https://doi.org/10.1038/sj.ijo.0801989
Garagorri, J. M., Rodríguez, G., Lario-Elboj, A. J., Olivares, J. L., Lario-Muñoz, A., & Orden, I. (2008). Reference levels for 17-hydroxyprogesterone, 11-desoxycortisol, cortisol, testosterone, dehydroepiandrosterone sulfate and androstenedione in infants from birth to six months of age. European Journal of Pediatrics, 167(6), 647-653. https://doi.org/10.1007/s00431-007-0565-1
Garnett, S. P., Högler, W., Blades, B., Baur, L. A., Peat, J., Lee, J., & Cowell, C. T. (2004). Relation between hormones and body composition, including bone, in prepubertal children. Amercian Journal of Clinical Nutrition, 80(4), 966-972. https://doi.org/10.1093/ajcn/80.4.966
Godhe, M., Helge, T., Forsberg, A., Karlsson, E., & Ekblom, B. (2019). Isokinetic muscle torque and endurance in limbs and trunk in children and adolescents: A longitudinal study. Clinical and Medical Investigations, 4(4). https://doi.org/10.15761/CMI.1000197
Greenhalgh, T., & Peacock, R. (2005). Effectiveness and efficiency of search methods in systematic reviews of complex evidence: audit of primary sources. British Medical Journal, 331(7524), 1064-1065. https://doi.org/10.1136/bmj.38636.593461.68
Hamilton, B., Brown, A., Montagner-Moraes, S., Comeras-Chueca, C., Bush, P. G., Guppy, F. M., & Pitsiladis, Y. P. (2024). Strength, power and aerobic capacity of transgender athletes: a cross-sectional study. British Journal of Sports Medicine. https://doi.org/10.1136/bjsports-2023-108029
Handelsman, D. J., Hirschberg, A. L., & Bermon, S. (2018). Circulating testosterone as the hormonal basis of sex differences in athletic performance. Endocrine Reviews, 39(5), 803-829. https://doi.org/10.1210/er.2018-00020
He, Q., Horlick, M., Thornton, J., Wang, J., Pierson, R. N., Jr., Heshka, S., & Gallagher, D. (2002). Sex and race differences in fat distribution among Asian, African-American, and Caucasian prepubertal children. Journal of Clinical Endocrinology and Metabolism, 87(5), 2164-2170. https://doi.org/10.1210/jcem.87.5.8452
Henche, S. A., Torres, R. R., & Pellico, L. G. (2008). An evaluation of patterns of change in total and regional body fat mass in healthy Spanish subjects using dual-energy X-ray absorptiometry (DXA). European Journal of Clinical Nutrition, 62(12), 1440-1448. https://doi.org/10.1038/sj.ejcn.1602883
Hilton, E. N., & Lundberg, T. R. (2021). Transgender women in the female category of sport: perspectives on testosterone suppression and performance advantage. Sports Medicine, 51(2), 199-214. https://doi.org/10.1007/s40279-020-01389-3
Hogrel, J. Y., Decostre, V., Alberti, C., Canal, A., Ollivier, G., Josserand, E., Taouil, I., & Simon, D. (2012). Stature is an essential predictor of muscle strength in children. BMC Musculoskeletal Disorders, 13, 176. https://doi.org/10.1186/1471-2474-13-176
Holm, I., Fredriksen, P., Fosdahl, M., & Vøllestad, N. (2008). A normative sample of isotonic and isokinetic muscle strength measurements in children 7 to 12 years of age. Acta Paediatrica, 97(5), 602-607. https://doi.org/10.1111/j.1651-2227.2008.00709.x
Ikai, M., & Fukunaga, T. (1968). Calculation of muscle strength per unit cross-sectional area of human muscle by means of ultrasonic measurement. Internationale Zeitschrift für angewandte Physiologie, einschliesslich Arbeitsphysiologie, 26(1), 26-32. https://doi.org/10.1007/bf00696087
Jones, G., & Dwyer, T. (1998). Bone mass in prepubertal children: gender differences and the role of physical activity and sunlight exposure. Journal of Clinical Endocrinology and Metabolism, 83(12), 4274-4279. https://doi.org/10.1210/jcem.83.12.5353
Jürimäe, T., Hurbo, T., & Jürimäe, J. (2009). Relationship of handgrip strength with anthropometric and body composition variables in prepubertal children. Homo, 60(3), 225-238. https://doi.org/10.1016/j.jchb.2008.05.004
Kanehisa, H., Ikegawa, S., & Fukunaga, T. (1994). Comparison of muscle cross-sectional area and strength between untrained women and men. European Journal of Applied Physiology and Occupational Physiology, 68(2), 148-154. https://doi.org/10.1007/BF00244028
Kanehisa, H., Ikegawa, S., Tsunoda, N., & Fukunaga, T. (1994). Strength and cross-sectional area of knee extensor muscles in children. European Journal of Applied Physiology and Occupational Physiology, 68(5), 402-405. https://doi.org/10.1007/bf00843736
Kanehisa, H., Ikegawa, S., Tsunoda, N., & Fukunaga, T. (1995). Strength and cross-sectional areas of reciprocal muscle groups in the upper arm and thigh during adolescence. International Journal of Sports Medicine, 16(1), 54-60. https://doi.org/10.1055/s-2007-972964
Kanehisa, H., Yata, H., Ikegawa, S., & Fukunaga, T. (1995). A cross-sectional study of the size and strength of the lower leg muscles during growth. European Journal of Applied Physiology and Occupational Physiology, 72(1-2), 150-156. https://doi.org/10.1007/bf00964130
Katzmarzyk, P. T., Malina, R. M., & Beunen, G. P. (1997). The contribution of biological maturation to the strength and motor fitness of children. Annals of Human Biology, 24(6), 493-505. https://doi.org/10.1080/03014469700005262
Khairullah, A., Klein, L. C., Ingle, S. M., May, M. T., Whetzel, C. A., Susman, E. J., & Paus, T. (2014). Testosterone trajectories and reference ranges in a large longitudinal sample of male adolescents. PLoS One, 9(9), e108838. https://doi.org/10.1371/journal.pone.0108838
Kirchengast, S. (2010). Gender Differences in Body Composition from Childhood to Old Age: An Evolutionary Point of View. Journal of Life Science, 2(1), 1-10.
Kiviranta, P., Kuiri-Hänninen, T., Saari, A., Lamidi, M. L., Dunkel, L., & Sankilampi, U. (2016). Transient Postnatal Gonadal Activation and Growth Velocity in Infancy. Pediatrics, 138(1). https://doi.org/10.1542/peds.2015-3561
Kocher, M. H., Oba, Y., Kimura, I. F., Stickley, C. D., Morgan, C. F., & Hetzler, R. K. (2019). Allometric Grip Strength Norms for American Children. Journal of Strength and Conditioning Research, 33(8), 2251-2261. https://doi.org/10.1519/jsc.0000000000002515
Kocher, M. H., Romine, R. K., Stickley, C. D., Morgan, C. F., Resnick, P. B., & Hetzler, R. K. (2017). Allometric Grip Strength Norms for Children of Hawaiian Lineage. Journal of Strength and Conditioning Research, 31(10), 2794-2807. https://doi.org/10.1519/jsc.0000000000001711
Kuczmarski, R. J., Ogden, C. L., & Guo, S. S. (2002). 2000 CDC growth charts for the United States: Methods and development. Vital Health Statistics, 11(246).
Kuijper, E. A., Ket, J. C., Caanen, M. R., & Lambalk, C. B. (2013). Reproductive hormone concentrations in pregnancy and neonates: a systematic review. Reproductive Biomedicine Online, 27(1), 33-63. https://doi.org/10.1016/j.rbmo.2013.03.009
Leppänen, M. H., Henriksson, P., Delisle Nyström, C., Henriksson, H., Ortega, F. B., Pomeroy, J., Ruiz, J. R., Cadenas-Sanchez, C., & Löf, M. (2017). Longitudinal Physical Activity, Body Composition, and Physical Fitness in Preschoolers. Medicine and Science in Sports and Exercise, 49(10), 2078-2085. https://doi.org/10.1249/mss.0000000000001313
Linderholm, H., Lindqvist, B., Ringqvist, M., & Wennström, A. (1971). Isometric Bite Force in Children and its Relation to Body Build and General Muscle Force. Acta Odontologica Scandinavica, 29(5), 563-568. https://doi.org/10.3109/00016357109026334
Lundberg, T. R., Tucker, R., McGawley, K., Williams, A. G., Millet, G. P., Sandbakk, Ø., Howatson, G., Brown, G. A., Carlson, L. A., Chantler, S., Chen, M. A., Heffernan, S. M., Heron, N., Kirk, C., Murphy, M. H., Pollock, N., Pringle, J., Richardson, A., Santos-Concejero, J., Stebbings, G. K., Christiansen, A. V., Phillips, S. M., Devine, C., Jones, C., Pike, J., & Hilton, E. N. (2024). The International Olympic Committee framework on fairness, inclusion and nondiscrimination on the basis of gender identity and sex variations does not protect fairness for female athletes. Scandinavian Journal of Medicine and Science in Sports, 34(3), e14581. https://doi.org/10.1111/sms.14581
Lundgren, S. S., Nilsson, J., Ringsberg, K. A., & Karlsson, M. K. (2011). Normative data for tests of neuromuscular performance and DXA-derived lean body mass and fat mass in pre-pubertal children. Acta Paediatrica, 100(10), 1359-1367. https://doi.org/10.1111/j.1651-2227.2011.02322.x
Manzano-Carrasco, S., Garcia-Unanue, J., Lopez-Fernandez, J., Hernandez-Martin, A., Sanchez-Sanchez, J., Gallardo, L., & Felipe, J. L. (2022). Differences in body composition and physical fitness parameters among prepubertal and pubertal children engaged in extracurricular sports: the active health study. European Journal of Public Health, 32(Suppl 1), i67-i72. https://doi.org/10.1093/eurpub/ckac075
McCarthy, H. D., Samani-Radia, D., Jebb, S. A., & Prentice, A. M. (2014). Skeletal muscle mass reference curves for children and adolescents. Pediatric Obesity, 9(4), 249-259. https://doi.org/10.1111/j.2047-6310.2013.00168.x
Miyashita, M., & Kanehisa, H. (1979). Dynamic peak torque related to age, sex, and performance. Research Quarterly for Exercise and Sport, 50(2), 249-255.
Montoye, H. J., & Lamphiear, D. E. (1977). Grip and arm strength in males and females, age 10 to 69. Research Quarterly, 48(1), 109-120. https://doi.org/10.1080/10671315.1977.10762158
Muehlbauer, T., Gollhofer, A., & Granacher, U. (2012). Sex-related effects in strength training during adolescence: a pilot study. Perceptual and Motor Skills, 115(3), 953-968. https://doi.org/10.2466/06.10.30.Pms.115.6.953-968
Nelson, D. A., & Barondess, D. A. (1997). Whole body bone, fat and lean mass in children: comparison of three ethnic groups. American Journal of Physical Anthropology, 103(2), 157-162. https://doi.org/10.1002/(sici)1096-8644(199706)103:2<157::Aid-ajpa2>3.0.Co;2-r
Nokoff, N. J., Senefeld, J., Krausz, C., Hunter, S., & Joyner, M. (2023). Sex differences in athletic performance: perspectives on transgender athletes. Exercise and Sport Sciences Reviews. https://doi.org/10.1249/jes.0000000000000317
Nuzzo, J. L. (2023). Narrative review of sex differences in muscle strength, endurance, activation, size, fiber type, and strength training participation rates, preferences, motivations, injuries, and neuromuscular adaptations. Journal of Strength and Conditioning Research, 37(2), 494-536. https://doi.org/10.1519/jsc.0000000000004329
Nuzzo, J. L. (2024a). PRE-PRINT - Child and adolescent sex differences in sit-and-reach flexibility: a meta-analysis. SportRxiv. https://doi.org/https://doi.org/10.51224/SRXIV.445
Nuzzo, J. L. (2024b). PRE-PRINT - Sex differences in grip strength from birth to age 16: a meta-analysis. SportRxiv. https://doi.org/https://doi.org/10.51224/SRXIV.441
Nuzzo, J. L., Pinto, M. D., & Nosaka, K. (2023). Muscle fatigue during maximal eccentric-only, concentric-only, and eccentric-concentric bicep curl exercise with automated drop setting. Scandinavian Journal of Medicine and Science in Sports. https://doi.org/10.1111/sms.14330
Nuzzo, J. L., Pinto, M. D., Nosaka, K., & Steele, J. (2023). The eccentric:concentric strength ratio of human skeletal muscle in vivo: meta-analysis of the influences of sex, age, joint action, and velocity. Sports Medicine, 53(6), 1125-1136. https://doi.org/10.1007/s40279-023-01851-y
Nuzzo, J. L., Pinto, M. D., Nosaka, K., & Steele, J. (2024). Maximal number of repetitions at percentages of the one repetition maximum: a meta-regression and moderator analysis of sex, age, training status, and sxercise. Sports Medicine, 54(2), 303-321. https://doi.org/10.1007/s40279-023-01937-7
O'Brien, T. D., Reeves, N. D., Baltzopoulos, V., Jones, D. A., & Maganaris, C. N. (2010). In vivo measurements of muscle specific tension in adults and children. Expimental Physiology, 95(1), 202-210. https://doi.org/10.1113/expphysiol.2009.048967
Ogle, G. D., Allen, J. R., Humphries, I. R., Lu, P. W., Briody, J. N., Morley, K., Howman-Giles, R., & Cowell, C. T. (1995). Body-composition assessment by dual-energy x-ray absorptiometry in subjects aged 4-26 y. American Journal of Clinical Nutrition, 61(4), 746-753. https://doi.org/10.1093/ajcn/61.4.746
Pääsuke, M., Ereline, J., Gapeyeva, H., Toots, M., & Toots, L. (2003). Comparison of Twitch Contractile Properties of Plantar Flexor Muscles in 9–10-Year-Old Girls and Boys. Pediatric Exercise Science, 15(3), 324-332. https://doi.org/10.1123/pes.15.3.324
Parker, D. F., Round, J. M., Sacco, P., & Jones, D. A. (1990). A cross-sectional survey of upper and lower limb strength in boys and girls during childhood and adolescence. Annals of Human Biology, 17(3), 199-211. https://doi.org/10.1080/03014469000000962
Peek, K., Ford, K. R., Myer, G. D., Hewett, T. E., & Pappas, E. (2022). Effect of Sex and Maturation on Knee Extensor and Flexor Strength in Adolescent Athletes. American Journal of Sports Medicine, 50(12), 3280-3285. https://doi.org/10.1177/03635465221118081
Perry, A. C., Tremblay, L. M., Signorile, J. F., Kaplan, T. A., & Miller, P. C. (1997). Fitness, diet and coronary risk factors in a sample of southeastern U.S. children. Applied Human Science, 16(4), 133-141. https://doi.org/10.2114/jpa.16.133
Ramos, E., Frontera, W. R., Llopart, A., & Feliciano, D. (1998). Muscle strength and hormonal levels in adolescents: gender related differences. International Journal of Sports Medicine, 19(8), 526-531. https://doi.org/10.1055/s-2007-971955
Raudsepp, L., & Paasuke, M. (1995). Gender differneces in fundamental movement patterns, motor performances, and strength measurements of prepubertal children. Pediatric Exercise Science, 7, 294-304. https://doi.org/https://doi.org/10.1123/pes.7.3.294
Ripka, W. L., Orsso, C. E., Haqq, A. M., Luz, T. G., Prado, C. M., & Ulbricht, L. (2020). Lean mass reference curves in adolescents using dual-energy x-ray absorptiometry (DXA). PLoS One, 15(2), e0228646. https://doi.org/10.1371/journal.pone.0228646
Round, J. M., Jones, D. A., Honour, J. W., & Nevill, A. M. (1999). Hormonal factors in the development of differences in strength between boys and girls during adolescence: a longitudinal study. Annals of Human Biology, 26(1), 49-62. https://doi.org/10.1080/030144699282976
Sartorio, A., Lafortuna, C. L., Pogliaghi, S., & Trecate, L. (2002). The impact of gender, body dimension and body composition on hand-grip strength in healthy children. Journal of Endocrinological Investigation, 25(5), 431-435. https://doi.org/10.1007/bf03344033
Seger, J. Y., & Thorstensson, A. (1994). Muscle strength and myoelectric activity in prepubertal and adult males and females. European Journal of Applied Physiology and Occupational Physiology, 69(1), 81-87. https://doi.org/10.1007/bf00867932
Seger, J. Y., & Thorstensson, A. (2000). Electrically evoked eccentric and concentric torque-velocity relationships in human knee extensor muscles. Acta Physiologica Scandinavica, 169(1), 63-69. https://doi.org/10.1046/j.1365-201x.2000.00694.x
Siegel, J. A., Camaione, D. N., & Manfredi, T. G. (1989). The Effects of Upper Body Resistance Training on Prepubescent Children. Pediatric Exercise Science, 1(2), 145-154. https://doi.org/10.1123/pes.1.2.145
Soininen, S., Sidoroff, V., Lindi, V., Mahonen, A., Kröger, L., Kröger, H., Jääskeläinen, J., Atalay, M., Laaksonen, D. E., Laitinen, T., & Lakka, T. A. (2018). Body fat mass, lean body mass and associated biomarkers as determinants of bone mineral density in children 6-8years of age - The Physical Activity and Nutrition in Children (PANIC) study. Bone, 108, 106-114. https://doi.org/10.1016/j.bone.2018.01.003
Streckis, V., Skurvydas, A., & Ratkevicius, A. (2007). Children are more susceptible to central fatigue than adults. Muscle & Nerve, 36(3), 357-363. https://doi.org/10.1002/mus.20816
Tanner, J. M. (1971). Sequence, Tempo, and Individual Variation in the Growth and Development of Boys and Girls Aged Twelve to Sixteen. Daedalus, 100(4), 907-930.
Taylor, R. W., Gold, E., Manning, P., & Goulding, A. (1997). Gender differences in body fat content are present well before puberty. International Journal of Obesity and Related Metabolic Disorders, 21(11), 1082-1084. https://doi.org/10.1038/sj.ijo.0800522
Thomas, J. R., & French, K. E. (1985). Gender differences across age in motor performance a meta-analysis. Psychological Bulletin, 98(2), 260-282. https://doi.org/10.1037/0033-2909.98.2.260
Thomas, J. R., Nelson, J. K., & Church, G. (1991). A developmental analysis of gender differneces in health related physical fitness. Pediatric Exercise Science, 3, 28-42. https://doi.org/10.1123/pes.3.1.28
Tomlinson, C., Macintyre, H., Dorrian, C. A., Ahmed, S. F., & Wallace, A. M. (2004). Testosterone measurements in early infancy. Archives of Disease in Childhood. Fetal and Neonatal Edition., 89(6), F558-F559. https://doi.org/10.1136/adc.2003.034017
Tucker, R., Hilton, E. N., McGawley, K., Pollock, N., Millet, G. P., Sandbakk, Ø., Howatson, G., Brown, G. A., Carlson, L. A., Chen, M. A., Heron, N., Kirk, C., Murphy, M. H., Pringle, J., Richardson, A., Santos-Concejero, J., Christiansen, A. V., Jones, C., Alonso, J. M., Robinson, R., Jones, N., Wilson, M., Parker, M. G., Chintoh, A., Hunter, S., Senefeld, J. W., O'Connor, M. I., Joyner, M., Carneiro, E. M., Devine, C., Pike, J., & Lundberg, T. R. (2024). Fair and Safe Eligibility Criteria for Women's Sport. Scandinavian Journal of Medicine and Science in Sports, 34(8), e14715. https://doi.org/10.1111/sms.14715
Welsman, J. R., Armstrong, N., Kirby, B. J., Winsley, R. J., Parsons, G., & Sharpe, P. (1997). Exercise performance and magnetic resonance imaging-determined thigh muscle volume in children. European Journal of Applied Physiology and Occupational Physiology, 76(1), 92-97. https://doi.org/10.1007/s004210050218
Wood, L. E., Dixon, S., Grant, C., & Armstrong, N. (2004). Elbow flexion and extension strength relative to body or muscle size in children. Medicine and Science in Sports and Exercise, 36(11), 1977-1984. https://doi.org/10.1249/01.mss.0000145453.02598.7e
Wood, L. E., Dixon, S., Grant, C., & Armstrong, N. (2006). Elbow Flexor Strength, Muscle Size, and Moment Arms in Prepubertal Boys and Girls. Pediatric Exercise Science, 18(4), 457-469. https://doi.org/10.1123/pes.18.4.457
Wood, L. E., Dixon, S., Grant, C., & Armstrong, N. (2008). Isokinetic elbow torque development in children. International Journal of Sports Medicine, 29(6), 466-470. https://doi.org/10.1055/s-2007-989234
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