Physical activity level and physical functionality in nonagenarians compared to individuals aged 60-74 years

Area of Science:

• Gerontology
• Human Physiology
• Biostatistics

Background:

• Functional dependence and disability risk increase with age.
• Decreased physical activity is a potential contributor to loss of independence.
• Accurate population-level physical activity measurement and its link to functional impairment are challenging.

Purpose of the Study:

• To objectively compare physical functionality and physical activity levels in nonagenarians versus younger older adults.
• To determine the contribution of physical activity and resting metabolic rate to reduced total energy expenditure in nonagenarians.

Main Methods:

• Assessed physical functionality using the Reduced Continuous Scale Physical Functional Performance Test (CS-PFP10).
• Measured physical activity levels via total energy expenditure (TEE) and resting metabolic rate (RMR).
• Compared nonagenarians (93 years) with a younger adult group (70 years) from the Louisiana Healthy Aging Study.

Main Results:

• Nonagenarians exhibited significantly lower TEE, RMR, and physical activity levels than the younger group (p<.001).
• Reduced functional performance was observed in nonagenarians (p<.001).
• Physical functionality was strongly correlated with physical activity levels (r=0.68, p<.001).

Conclusions:

• Reduced physical activity accounts for 73% of the decrease in TEE in nonagenarians, with the remainder due to lower RMR.
• Lower physical activity levels in nonagenarians are directly associated with diminished physical functionality.
• This study offers the first objective comparison of physical functionality and actual physical activity in very old individuals.