Relationship of Extremity Muscle Torque and Bone Mineral Density in Postmenopausal Women

Abstract

The purpose of this study was to examine the correlations between the torque of four extremity muscle groups and the bone mineral density (BMD) of the lumbar spine and hip in postmenopausal women. Fifty-six postmenopausal women (means age = 55.4 years, s = 7.1; means height = 162.6 cm, s = 6.4; means weight = 65.9 kg, s = 9.3) served as subjects. Bone mineral density was measured from the L2-L4 vertebral bodies, greater trochanter, femoral neck, and Ward's triangle using dual-photon absorptiometry. Hip abduction, knee extension, hip flexion, and grip force were assessed using the Spark Muscle Examination and Exercise Dosimeter (MEED) 3000 system. The Pearson product-moment correlations between muscle torque and BMD ranged from .07 to .42. The significant (p less than .05) correlations between torque and BMD (r = .27-.42) occurred in functionally and anatomically related areas. Results of this study demonstrate a statistically significant relationship between torque and BMD in anatomically related areas in postmenopausal women. This relationship, however, is not sufficiently strong to allow for prediction of BMD from the four muscle groups tested in this study. The relationship does suggest that strength may be a factor in the determination of BMD. Maintenance of strength in those muscle groups with anatomical or functional relationships to the hip and lumbar spine may play a role in the prevention and cessation of the osteoporotic changes that occur.

Effects of one year of resistance training on the relation between muscular strength and bone density in elderly women

“…Our data show significant relations between the quadriceps muscle strength and femoral-lumbar bone density changes over one year of exercise. Zimmerman et al 27 and Bevier et al 28 have reported similar findings in postmenopausal women. It would seem that, if muscular strength is to be a determinant of bone density, the force of muscle contraction must impact on an anatomically related skeletal site or reflect actions of those muscles that do.…”

Regional bone mineral density after resistive training in young and older men and women

“…Bone density is positively associated with the strength of the anatomically related structures (Sinaki et al, 1986; Zimmermann et al, 1990). Furthermore, positive associations between bone mass and fat‐free mass (Aloia et al, 1995) and between BMD and muscular strength (Ryan et al, 1998) have been reported previously.…”

Effects of Age-Related Differences in Femoral Loading and Bone Mineral Density on Strains in the Proximal Femur During Controlled Walking

“…Furthermore, femoral neck BMD is significantly correlated with hip abductor and flexor strength in postmenopausal women. 7,8 Finite element modeling studies have been widely used to examine bone remodeling, for example following total hip replacement, 9 with remodeling stimulus based on local strain energy density. However, there has been little examination of age-related differences in strains in the healthy intact femur, which may have implications for bone remodeling processes and maintenance of bone health in older adults.…”