Differences in muscle strength between people with loose joints and those without
Generalized joint hypermobility (GJH) without symptoms is a common clinical finding. Joint instability in the presence of excessive musculoskeletal flexibility can have an effect during muscle contraction. However, it is not known whether GJH is associated with muscle weakness, so this study will evaluate differences in upper and lower extremity strength in asymptomatic young adults with and without GJH.
166 young adults
53 hypermobile, 25 males (mean age 22 ± 1.8); 28 females (mean age 21 ± 1.8) and 53 nonhypermobile, 25 males (mean age 19 ± 1.06); 28 females were selected as participants. An isokinetic dynamometer was used to measure isometric strength of the elbow and knee extensors, and unidirectional ANCOVA was applied to control for the effects of height and weight on muscle strength.
Results.
Male participants with hypermobility
Right (71.7 Nm, SD = 23.1, vs 97.6 Nm, SD = 47.4, p = 0.006*)
Left (74.8 Nm, SD = 24.3, vs 97.7 Nm, SD = 45.5, p = 0.007*)
Elbow and right knee extensors (188.7 Nm, SD = 83.3, vs 228.3 Nm, SD = 106.7, p = 0.03*)
In women.
Both elbow extensors (right: 51.9 Nm, SD = 16.2 vs 48.8 Nm, SD = 17.8, p = 0.4; left: 48.9 Nm, SD = 17.2 vs 44.7 Nm, SD = 15.1, p = 0.2)
Knee extensors (right: 161.3 Nm, SD = 74.9 vs 145.5 Nm, SD = 75.8, p = 0.3; left: 155.2 Nm, SD = 73 vs 124.3 Nm, SD = 69.6, p = 0.07)
Muscle strength was not statistically different between participants with and without hypermobility.
In conclusion, we found that in males with hypermobility, elbow extensor strength and right knee extensor strength had significantly lower isometric muscle strength, while in females there was no significant difference between the two groups.
Jindal, P., Narayan, A., Ganesan, S. et al. Muscle strength differences in healthy young adults with and without generalized joint hypermobility: a cross-sectional study. BMC Sports Sci Med Rehabil 8, 12 (2016). Available at: https://doi.org/10.1186/s13102-016-0037-x
Conclusion
The study was conducted on Asian young adults, so it is unclear what the results would be for children or the elderly, but it was also clinically applicable.
As a personal matter, I have my own hypermobility, so I was wondering how much of this research applies to me? I am aware that my elbow and knee extension muscles are weak.
I was aware that my elbows and knees are not strong enough to extend them, and this is something I've learned through weight training and MMT, so I thought I was just bad at it. However, hypermobility can never be cured, so the only thing you can do is to do muscle exercises that are appropriate for it.
