Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.
IRCCS Istituto Ortopedico Galeazzi, Milan, Italy.
Medicine (Baltimore). 2022 Jul 1;101(26):e29744. doi: 10.1097/MD.0000000000029744.
The aim of this cross-sectional study was to investigate the association between lower limb strength, muscle mass and composition, and balance ability in elders. Thirthy-four older participants (Age: 65.6 ± 4.73 years; male = 10 and female = 24) were assessed for muscle strength (maximal isometric strength of knee extensors and one repetition maximum by leg press, the one repetition maximum [1RM]), balance and gait capacity (Mini-BESTest), body composition by whole-body dual energy x-ray absorptiometry (obtaining Appendicular Skeletal Muscle Mass Index, ASMMI), and magnetic resonance imaging of thigh to evaluate Intermuscular Adipose Tissue (IMAT) and muscle Cross Sectional Area (CSA). Positive correlations between 1RM and ASMMI (rs = 0.64, P < .0001) and thigh CSA (rs = 0.52, P = .0017), but not with thigh IMAT, were found. In addition, significant correlations between knee extensors strength and ASMMI (rs = 0.48, P = .004) and thigh CSA (rs = 0.49, P = .0033) and IMAT (rs = -0.35, P = .043) were observed, whereas no significant correlations between the Mini-BESTest with ASMMI, thigh CSA, and IMAT were observed. Lower limb strength positively correlated with appendicular muscle mass. Further, the maximal isometric strength of knee extensors negatively correlated with thigh IMAT in elderly patients, whereas the dynamic balance ability did not correlate with any of the morphological variables of the muscle (i.e., ASMMI, CSA, and IMAT). A reduced muscle size and strength could affect movement and reduce physical function in older patients. Improving the composition and size of muscle in elder subjects could reduce frailty and risk of falls.
本横断面研究旨在探讨老年人下肢力量、肌肉质量和组成与平衡能力之间的关系。34 名老年人（年龄：65.6±4.73 岁；男性=10 名，女性=24 名）接受了肌肉力量（膝关节伸展的最大等长力量和腿部按压的最大重复次数 1 次重复最大值[1RM]）、平衡和步态能力（Mini-BESTest）、全身双能 X 射线吸收法（获得四肢骨骼肌质量指数[ASMMI]）和大腿磁共振成像评估肌肉内脂肪组织（IMAT）和肌肉横截面积（CSA）。1RM 与 ASMMI（rs=0.64，P<.0001）和大腿 CSA（rs=0.52，P=0.0017）呈正相关，但与大腿 IMAT 无关。此外，膝关节伸展力量与 ASMMI（rs=0.48，P=0.004）和大腿 CSA（rs=0.49，P=0.0033）和 IMAT（rs=-0.35，P=0.043）呈显著相关，而 Mini-BESTest 与 ASMMI、大腿 CSA 和 IMAT 之间无显著相关性。下肢力量与四肢肌肉质量呈正相关。此外，在老年患者中，膝关节伸展的最大等长力量与大腿 IMAT 呈负相关，而动态平衡能力与肌肉的任何形态学变量（即 ASMMI、CSA 和 IMAT）均无相关性。肌肉体积和力量的减少可能会影响运动并降低老年人的身体功能。改善老年受试者的肌肉组成和大小可以减少虚弱和跌倒风险。
