Reference Values for Concentric Knee Isokinetic Strength and Power in Nonathletic Men and Women from 20 to 80 Years Old
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STUDY DESIGN: A prospective, controlled, randomized study. OBJECTIVE: To establish reference values for prediction of concentric isokinetic knee strength and power in a sample of nonathletic men and women. BACKGROUND: Adequate interpretation of knee isokinetic strength and power relies on a representative frame of reference. However, none of the most widely cited prediction studies used a randomly selected sample of nonathletic subjects, therefore limiting the clinical application of these studies. METHODS AND MEASURES: We evaluated the concentric right and left knee extensor and flexor peak torque, total work, set total work, average power, and torque acceleration energy (Cybex 6000 System) in 96 healthy subjects (45 men and 51 women, aged 20 to 80), randomly selected from more than 8000 individuals. RESULTS: By stepwise regression analysis, we found that gender, age, weight, height, and regular physical activity explained up to 84% of the variability of the dependent variables: a set of linear prediction equations for strength (at 60 degrees/s) and power (at 300 degrees/s) is provided. CONCLUSIONS: Results from this study might provide a clinically useful frame of reference for interpretation of concentric isokinetic knee strength and power in nonathletic men and women.
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Cisgender women demonstrate 31% lower lean body mass, 36% lower hand-grip strength, and 35% lower knee extension strength than cisgender men.
“cisgender women demonstrating 31% lower LBM,59 36%60 lower hand-grip strength and 35%61 lower knee extension strength than cisgender men”
Transwomen likely retain a strength advantage over cisgender women after 12-36 months of GAHT.
“the small decrease in strength in transwomen after 12–36 months of GAHT suggests that transwomen likely retain a strength advantage over cisgender women.”
Males have longer and larger skeletal structure than females, creating advantages in sports where levers influence force application, longer limb/digit length is favorable, and height, mass and proportions are directly responsible for performance capacity.
“longer and larger skeletal structure, which creates advantages in sports where levers influence force application, where longer limb/digit length is favorable, and where height, mass and proportions are directly responsible for performance capacity”
From Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage (2021) · cites this paper as [31]
Males have reduced fat mass and different distribution of body fat and lean muscle mass compared with females, which increases power to weight ratios and upper to lower limb strength.
“reduced fat mass, and different distribution of body fat and lean muscle mass, which increases power to weight ratios and upper to lower limb strength in sports where this may be a crucial determinant of success”
From Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage (2021) · cites this paper as [31]
Males have larger and denser muscle mass, and stiffer connective tissue, with associated capacity to exert greater muscular force more rapidly and efficiently than females.
“Males have: larger and denser muscle mass, and stiffer connective tissue, with associated capacity to exert greater muscular force more rapidly and efficiently”
From Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage (2021) · cites this paper as [31]
Records of lower-limb muscle strength reveal a consistent 50% difference in peak torque between males and females across the lifespan.
“Records of lower-limb muscle strength reveal a consistent 50% difference in peak torque between males and females across the lifespan [31].”
From Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage (2021) · cites this paper as [31]
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References 26 · Cited by 143
- Authors
- Neder, J. A., Nery, L. E., Shinzato, G. T., Andrade, M. S., Peres, C., & Silva, A. C.
- Affiliations
- University of London (GB)
- Venue
- Journal of Orthopaedic & Sports Physical Therapy
- Published
- 1999-02
- Volume
- 29
- Issue
- 2
- Pages
- 116-126
- ISSN
- 0190-6011 (ISSN-L)
- 1938-1344
- OpenAlex
- W2085730915
- Cited by
- 143
- References
- 26
- Citations by year
- 2026: 3 · 2025: 7 · 2024: 5 · 2023: 7 · 2022: 9 · 2021: 10 · 2020: 8 · 2019: 8 · 2018: 8 · 2017: 3 · 2016: 7 · 2015: 6 · 2014: 5 · 2013: 2 · 2012: 8
- FWCI
- 2.85
- Type
- journal article
- Language
- en
- Open access
- green
- americanae.aecid.es
- Licence
- other-oa
- Locations
- Journal of Orthopaedic and Sports Physical Therapy (publishedVersion)
- PubMed (publishedVersion)
- Americanae (AECID Library) (submittedVersion, other-oa)
- LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) (submittedVersion, other-oa)
- Topics
- Physical Sciences › Engineering › Biomedical Engineering › Lower Extremity Biomechanics and Pathologies
- Health Sciences › Medicine › Surgery › Knee injuries and reconstruction techniques
- Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
- Keywords
- reference values, knee extensors, knee flexors, peak torque, prediction equations, age and sex differences, physical activity, healthy adults
- MeSH terms
- Adult, Aged, Aged, 80 and over, Female, Humans, Knee, Male, Middle Aged, Prospective Studies, Surveys and Questionnaires, Reference Values, Regression Analysis, Exercise, Muscle, Skeletal, Torque
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