Maximal isometric strength in older adults : cross-national comparisons, background factors and association with mobility

Abstract

The aim was to study the levels and background factors of maximal isometric strength in older adults, as well as the association of strength with mobility. 75-year-old men and women were studied in three Nordic localities (Glostrup, Denmark; Gothenburg, Sweden; and Jyväskylä, Finland) to compare strength levels and anthropometric characteristics between populations. Socio-economic status, health and everyday physical activity as background factors of maximal strength were then studied among the 75-year-old residents of Jyväskylä. The association between life-long physical exercise, educational background and work history with strength were investigated in specially selected groups of women aged 50-60 years and 66-85 years. Altogether, 1113 individuals took part in the maximal isometric strength tests. Maximal isometric strength of hand grip, elbow flexion, knee extension, trunk flexion and extension were measured with the aid of specially constructed dynamometers. Significant differences in the strength were observed between the 75-year-olds in Glostrup, Gothenburg and Jyvaskyla partly owing to differences in basic anthropometric characteristics. Poorer values in the state-of-health indicators correlated with lower strength and greater amount of everyday physical activity with better strength. Women with life-long history of physical exercise exhibited greater force values than their sedentary controls. Among the 50-60-year-old women a university level educational background was connected with greater muscle strength, whereas among the older persons education or former occupation were not associated with strength. Greater strength was connected with better locomotor abilities.