Background:Past surveys indicate that physical fitness has significant correlation with body weight, however, the body weight of Chinese civilians seems to augment in recent years,
which is one of the most essential factors results in the declination of the national physical fitness. Due to the variation of individual weight is actually the change of body composition, thus
relevant questions have become the hot spot. By collecting massive simples data and focusing on the relation between body composition and physical fitness, this survey tried to work out the rule how
the change of individual body composition the physical fitness. We also carried on practical research in order to make more scientific, timely suggests for government.
Methods:1. Subjects: subjects are Chinese citizens aged from 20~69 and total sample amount reaches 21080 persons, which is divided into 20 groups by the criterion of age of 5 and
gender. Every group holds 1000 persons at least.
Measurement Index: Each participant takes the body composition test and physical fitness test. Body composition indexes include body fat percentage, rate of skeletal muscle, ratio of fat and muscle.
The fitness tests include anthropometry, physiological fitness and physical activity.
2. Mathematic statistics: By applying the software SPSS11.0 acquiring and analyzing data.
Results:1. Ratio of fat and muscle has significant effects on physical fitness. Rate of skeletal muscle is positive correlated with physical fitness. Meanwhile, there is a “threshold”
lies in the relation between ratio of fat and physical fitness: Over the threshold, ratio of fat is negative correlated with physical fitness.
2. Rate of skeletal muscle is positive correlated with some indexes of test of physical activity like reaction time, step test, grip.
3. Ratio of fat is correlated with the indexes of step test, sit and reach, balancing on one leg with eyes closed, while there is no significant correlation with the other indexes.
4. As the age grows, the negative changes of ratio of fat and muscle have more negative effects on physical fitness.
5. In general, the effect on physical fitness caused by the variation of rate of skeletal muscle is less significant in male rather than in female, and as the age grows this difference become even
Conclusions:1. It is necessary for framing the regional evaluation criterion of body composition and it should be applied in the national physical fitness monitoring. Meanwhile,
Research on the body composition relations with social psychology should be kept carry out.
2. There is practical significance that body composition should be included in the national physical fitness monitoring as a sensitive index and government should carry out the monitoring of national
3. Exercise controlling fat content, while increasing muscle content should be placed as an essential role in the sport for all and promoted by government.
4. It seems that females pay less attention on strength exercise, which reveals there is greater meaning taking the strength exercise for female, especially for the elder one.