Changes in Flexibility in Older Adults Aged 55-86 Years and the Influence of Physical Activity

Abstract

Joint flexibility may decrease with age and this has the potential to affect normal daily function. The literature describing the influence of physical activity on flexibility on the aging process is limited. PURPOSE: To examine the cross-sectional age-related differences in flexibility in a large sample of independently living men and women aged 55-86 years of varying activity levels. METHODS: Flexibility measurements were obtained from a total of 439 individuals (208 men, mean age 70.5 ± 8.8 years; 231 women, mean age 71.5 ± 8.4 years). Flexibility was determined for both shoulder abduction (degrees) and hip flexion (degrees) using a Leighton Flexometer. Total physical activity was assessed using the Minnesota Leisure-Time Physical Activity Questionnaire. RESULTS: A mean lower body flexibility of 108 ± 20.7 degrees was observed for hip flexion in 402 individuals (183 men, 219 women). Women had significantly greater hip flexion (p=0.00) versus men. Upper body flexibility as assessed by shoulder abduction was measured in 436 individuals (205 men, 231 women) resulting in a mean of 138 ± 16 degrees. There was no significant difference based on sex (p=0.72). Age-related differences in flexibility were fit by linear regression yielding significant declines in hip flexion of 0.6 degrees/year in males and 0.7 degrees/year in females and in shoulder abduction of 0.5 degrees/year in males and 0.6 degrees/year in females. The mean total physical activity levels of the 434 individuals was 406± MET/min/day (men 386 ± 182, women 423 ± 215, p=0.06). The influence of age and level of physical activity on flexibility was determined by multiple regression. This model accounted for only 9% of the variance in hip flexion in women and 10% in men, with age remaining significant but the contribution of physical activity levels to lower body flexibility not significant for either males (p=0.71) or females (p=0.42). Similarly for shoulder abduction, age was significant but physical activity was not in a model that described 8% of the variance for both females (p=0.14) and males (p=0.57). CONCLUSIONS: A lower flexibility of the hip and shoulder joints by ∼6 degrees per decade, was observed across ages 55 to 86 years. Physical activity levels of older adults did not contribute to (or explain) the variance in hip and shoulder flexibility measures.