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Normative values for maximum power during motor function assessment of jumping among physically active Japanese.
A Tsubaki1, M Kubo, R Kobayashi
1Department of Physical Therapy, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, Japan. tsubaki@nuhw.ac.jp
Journal of Musculoskeletal & Neuronal Interactions
|December 2, 2009
Summary
Maximum power relative to body weight (Pmax-rel) significantly declines with age in Japanese individuals, mirroring European trends. This metric can assess physical function across diverse populations.
Area of Science:
- Sports Science
- Gerontology
- Human Physiology
Background:
- Maximum power relative to body weight (Pmax-rel) is a key indicator of physical function.
- Understanding age-related changes in Pmax-rel is crucial for maintaining motor function in aging populations.
Purpose of the Study:
- To investigate the relationship between Pmax-rel and aging in Japanese individuals.
- To establish target values for motor function improvement.
- To compare Japanese Pmax-rel data with European benchmarks.
Main Methods:
- Counter-movement jumps were performed by 410 physically active Japanese subjects (aged 7-79).
- Correlations between age and Pmax-rel were analyzed.
- Mean Pmax-rel by age group and percentage Esslinger Fitness Index (%EFI) scores were evaluated by gender.
Main Results:
- Pmax-rel showed a significant correlation with age in both males and females across different age brackets (p<0.01).
- Pmax-rel gradually decreased with age, reaching 53.5% of peak levels in individuals in their 70s.
- %EFI scores showed no significant differences across most age groups.
Conclusions:
- Pmax-rel in Japanese individuals is strongly age-dependent, similar to Europeans.
- Pmax-rel declines substantially by the 70s, highlighting age-related motor function loss.
- Pmax-rel and %EFI are suitable normative indices for assessing physical function across populations.
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