TITLE:
Characteristics of Body Composition and Relationship between Muscle Mass and Muscle Strength among Elderly Women in Different Age Groups
AUTHORS:
Nao Nishioka Nishi, Noriko Tanaka, Naomi Hirano
KEYWORDS:
Elderly Women, Body Composition, Muscle Mass, Muscle Strength
JOURNAL NAME:
Advances in Aging Research,
Vol.11 No.5,
September
16,
2022
ABSTRACT: Age-related changes in the body composition of older adults differ among
age groups. The purpose of the present study was to clarify the characteristics
of body compositions in young (age, 65 - 74 years; yE group) and old (age, ≥75 years; oE
group) elderly women, and compare the relationship between muscle mass and
strength in elderly women with that in young women for preventing motor
function loss in older adults. A total of 30 elderly and 45 young women aged ≥ 65 and 19 - 22 years, respectively,
participated in this study. The participants underwent body composition
measurement via bioelectrical impedance analysis and examinations of handgrip
and leg muscle strength. The age-related body composition changes varied among
age groups. Compared with young women, fat-free mass (FFM) in the yE group did
not decrease significantly; however, fat mass (FM) and waist-hip ratio (WHR) were
significantly greater. Compared with the yE group, decreases in FFM, FM, and
WHR in the oE group were significant; furthermore, the decrease in FM
measurements was attributed to the loss of FM in the trunk and limbs (upper and
lower). The measurement results suggested that the greater FM decrease in the
oE group was characterized by decreases in both visceral and subcutaneous fat.
In the yE group, the muscle mass was comparable to that in young women;
however, there was a remarkable reduction in the lower-limb muscle mass (9% - 10%). In the oE group,
muscle mass was reduced in all body parts, including upper and lower limbs and
trunk. In young women, significant positive correlations between muscle mass
and muscle strength in the upper and lower limbs were observed. No such
correlations in the lower limbs were found in elderly women, indicating that
muscle mass is not proportionally reflected in muscle strength. In conclusion,
for improving and maintaining the health of elderly women, especially those
above the age of 75 years, it is important to maintain muscle mass, including
muscle strength, and prevent the loss of muscle quality.