Difference between "Physical Fitness Age" Based on Physical Function and Chronological Age Is Associated with Obesity, Hyperglycemia, Depressive Symptoms, and Low Serum Albumin

OBJECTIVES

This study aimed to (1) develop the physical fitness age, which is the biological age based on physical function, (2) evaluate the validity of the physical fitness age for the assessment of sarcopenia, and (3) examine the factors associated with the difference between physical fitness age and chronological age.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

Community-dwelling older adults and outpatients.

MEASUREMENTS

A formula for calculating the physical fitness age was created based on the usual walking speed, handgrip strength, one-leg standing time, and chronological age of 4,076 older adults from the pooled data of community-dwelling and outpatients using the principal component analysis. For the validation of the physical fitness age, we also used pooled data from community-dwelling older adults (n = 1929) and outpatients (n = 473). Sarcopenia was diagnosed according to the Asian Working Group for Sarcopenia 2019 consensus. The association of D-age (the difference between physical and chronological ages) with cardiovascular risk factors, renal function, and cardiac function was examined.

RESULTS

The receiver operating characteristic analysis, with sarcopenia as the outcome, showed that the area under the curve (AUC) of physical fitness age was greater than that of chronological age (AUC 0.87 and 0.77, respectively, p < 0.001). Binomial logistic regression analysis revealed that the D-age was significantly associated with sarcopenia after adjustment for covariates (odds ratio 1.22, 95% confidence interval 1.19-1.26; p <0.001). In multivariate linear regression analysis with D-age as the dependent variable, D-age was independently associated with a history of diabetes mellitus (or hemoglobin A1c as a continuous variable), obesity, depression, and low serum albumin level. D-age was also correlated with estimated glomerular filtration rate derived from serum cystatin C, brain natriuretic peptide, and ankle-brachial index, reflecting some organ function and arteriosclerosis.

CONCLUSIONS

Compared to chronological age, physical fitness age calculated from handgrip strength, one-leg standing time, and usual walking speed was a better scale for sarcopenia. D-age, which could be a simple indicator of physical function, was associated with modifiable factors, such as poor glycemic control, obesity, depressive symptoms, and malnutrition.

Physical Fitness Levels among Colon Cancer Survivors with a Stoma: A Preliminary Study

Background and Objectives: Stoma surgery is linked to reduced physical activity in colon cancer survivors and leads to decreased physical fitness, activity of daily living dysfunction, and poorer quality of life. However, few studies have investigated the physical fitness levels of colon cancer survivors living with stomas. This study aimed to compare the physical fitness levels of colon cancer survivors with stomas and healthy adults, assessing them in a variety of dimensions (e.g., strength and flexibility) and in terms of physical fitness age (PFA), an integrated index of overall fitness. Materials and Methods: The study population consisted of 17 colon cancer survivors with (stoma group) and 20 healthy adults without (control group) a stoma. Physical fitness was assessed using a battery of five tests: repeated back-and-forth steps, 30-s chair stand, chair sit-and-reach, grip strength, and single-leg balance with eyes closed. Respective performance values were converted into PFA, which was compared between the stoma and control groups. Fitness indicators were compared between groups by analysis of covariance, and PFA and chronological age (CA) by paired t-tests. Results: The mean ages (±standard deviation) of the stoma and control groups were 74.1 ± 7.9 and 73.5 ± 7.1 years, respectively. Colon cancer survivors with stomas had poorer lower limb muscular strength, endurance, and flexibility than controls. In the stoma group, the marginal mean (±standard error) PFA was calculated to be 82.5 ± 3.7 years, significantly higher than the CA and PFA of the control group (69.6 ± 3.9 years). Conclusions: Colon cancer survivors with stomas have lower physical fitness levels than healthy adults, with apparent deficits in lower limb flexibility, muscular strength, and endurance. Our findings demonstrated the need for exercise interventions in this population, focusing on these dimensions of fitness. However, our results should be corroborated by means of a larger-scale comparison in future studies.

Developing an assessment based on physical fitness age to evaluate motor function in frail and healthy elderly women

Objectives

The purpose of this study was to identify a method for assessing physical fitness age that is easy to use with both frail and healthy elderly women and to examine its validity.

Methods

Principal component analysis was used to develop a formula of physical fitness age from four motor function variables. The subjects comprised 688 (75.7±6.0 years) elderly women, in order to develop a physical fitness scale. The formula for calculating physical fitness age was expressed as physical fitness age =-0.419× grip strength -0.096× balancing on one leg with eyes open -0.737×30 s chair stand +0.503× figure-of-8 walking test +0.47× chronological age +52.68.

Results

Measures obtained from subjects in the frail elderly (n=11, 73.0±2.3 years) and exercise (n=10, 70.8±3.1 years) groups were used to examine the validity of the assessment. The mean physical fitness age of the frail elderly group (79.0±3.7 years) was significantly higher than its mean chronological age (73.0±2.3 years, p<0.05). The mean physical fitness age of the exercise group (65.6±3.1 years) was significantly lower than the chronological age (70.8±3.1 years, p<0.05).

Conclusion

These findings confirm that physical fitness age scores are applicable to frail and healthy elderly women. Physical fitness age is a valid measure of motor function in elderly women.

Constructing an index of physical fitness age for Japanese elderly based on 7-year longitudinal data: sex differences in estimated physical fitness age

A standardized method for assessing the physical fitness of elderly adults has not yet been established. In this study, we developed an index of physical fitness age (fitness age score, FAS) for older Japanese adults and investigated sex differences based on the estimated FAS. Healthy elderly adults (52 men, 70 women) who underwent physical fitness tests once yearly for 7 years between 2002 and 2008 were included in this study. The age of the participants at the beginning of this study ranged from 60.0 to 83.0 years. The physical fitness tests consisted of 13 items to measure balance, agility, flexibility, muscle strength, and endurance. Three criteria were used to evaluate fitness markers of aging: (1) significant cross-sectional correlation with age; (2) significant longitudinal change with age consistent with the cross-sectional correlation; and (3) significant stability of individual differences. We developed an equation to assess individual FAS values using the first principal component derived from principal component analysis. Five candidate fitness markers of aging (10-m walking time, functional reach, one leg stand with eyes open, vertical jump and grip strength) were selected from the 13 physical fitness tests. Individual FAS was predicted from these five fitness markers using a principal component model. Individual FAS showed high longitudinal stability for age-related changes. This investigation of the longitudinal changes of individual FAS revealed that women had relatively lower physical fitness compared with men, but their rate of physical fitness aging was slower than that of men.