Maximal Isometric Strength and Mobility among 75-year-old Men and Women

Abstract

The purpose of this study was to examine the association between maximal isometric strength and mobility among 75-year-old men and women. All those born in 1914 and resident in the city of Jyväskylä in August 1989 comprised the study group (n = 388); 355 persons were interviewed at their homes (92%): 101 men (81% of all male residents) and 186 women (75%) participated in the laboratory strength tests. As part of the home interview the person's mobility at home, on stairs and outdoors was assessed using a four-point scale:--1 able, 2--able with difficulty, 3--needs help, 4--unable. Poor mobility was more common among the drop-outs than among the strength-tested subjects in both sexes. Maximal isometric strength of hand grip, arm flexion, knee extension and trunk flexion and extension were measured using specially constructed dynamometers. The strength results were adjusted for body weight. The study also included a stair-mounting test and measurement of maximal walking speed. The body-weight adjusted maximal forces were consistently significantly associated with mobility. Those who claimed no problems in the mobility interview and performed better in the walking and stair-mounting tests exhibited greater maximal isometric strength. The present results indicate that maximal isometric strength tests provide useful information about physical functional capacity among elderly people. These findings also suggest that the maintenance of adequate strength could be favourable to the mobility of older persons.

Association of Thigh Muscle Strength With Knee Symptoms and Radiographic Disease Stage of Osteoarthritis: Data From the Osteoarthritis Initiative

“…Baseline measurements for maximum isometric extensor and flexor strength were drawn from the OAI database (clinical data set 0.2.2) (32). These measurements were obtained using the Good Strength Chair (Metitur Oy) (6,33,34), with the participant sitting upright with a fixed pelvis and thigh. The knee was placed in 60°of flexion for testing.…”

Isometric muscle force measurement for clinicians treating patients with osteoarthritis of the knee

“…Examining our data using extensor force adjusted for body height and weight (Newtons/kg.m) as described by Rantanen et al (14) suggests that ϳ50% of this sample would not be able to mount a step Ն20 cm in height using the affected limb. For men in the sixth and seventh decades of life, the mean extensor force was 1.38 and 1.31 Newtons/kg.m, respectively, while corresponding values for women were 1.24 and 0.96 Newtons/kg.m.…”

“…More importantly, several cross-sectional studies have established that reduced knee extensor strength in people with knee OA is strongly associated with increased pain and poor physical function (10 -12). In fact, threshold values below which knee extensor strength is critical for independent walking, standing balance, and sit-stand function have been demonstrated (13)(14)(15)(16).…”

Grip strength and healthy aging

“…However, more dropout rates were observed in follow-up studies for knee extension strength and power than for grip strength because many of the participants who had serious pain, physical injury, or illness could not perform the measurements. Although lower muscle function such as knee extension strength is considered an important determinant factor of mobility 13) , an underCorrespondence: kozakai@hokusho-u.ac.jp estimated age-related decline in knee extension strength should be considered because of the possible bias associated with healthier/stronger people 14) . Grip strength could therefore be the most acceptable indicator for general muscle strength in a broad range of community-dwelling individuals.…”