Jaak Jürimäe

Growth, physical activity, and motor development in prepubertal children

MAIN FACTORS INFLUENCING THE DEVELOPMENT OF PREPUBERTAL CHILDREN Biological Maturation Influence of Environmental Factors Health, Physical Activity, and Inactivity ANTHROPOMETRIC DEVELOPMENT OF PREPUBERTAL CHILDREN Introduction Somatic Growth Main Anthropometric Parameters Somatotype Body Composition Tracking Anthropometric Parameters and Body Composition General Considerations PHYSICAL ACTIVITIES OF PREPUBERTAL CHILDREN Introduction Health Benefits of Physical Activity Assessment of Physical Activity Physical Activity Guidelines Physical Activity of Children in Different Countries Tracking Physical Activity The Influence of Physical Activity on Anthropometric Parameters and Motor Ability General Considerations MOTOR ABILITIES OF PREPUBERTAL CHILDREN Introduction Health-Related Physical Fitness Biological Maturation and Motor Ability Anthropometry and Motor Ability Physical Activity and Motor Ability Genetic Determination of Motor Ability Competitive Sports and Motor Ability Measurement Methods Motor Abilities of Children in Different Countries Tracking Motor Ability General Considerations MOTOR SKILLS OF PREPUBERTAL CHILDREN Introduction Basic Motor Skills Relationships among Motor Skills, Physical Activities, Motor Abilities, and Somatic Development General Considerations CONCLUSIONS AND PERSPECTIVES REFERENCES APPENDICES INDEX

Relationships between contraction properties of knee extensor muscles and fasting IGF-1 and adipocytokines in physically active postmenopausal women.

The aim of this cross‐sectional study was to find possible relationships between insulin‐like growth factor‐1 (IGF‐1), adipocytokines (leptin and adiponectin) and twitch contraction (TC) characteristics of the knee extensor (KE) muscles in healthy physically active postmenopausal women (n = 28, 64–78 years old). We hypothesized that IGF‐1 is related at least to isometric TC peak torque (Pt) as the highest value of isometric torque production and maximal voluntary contraction (MVC) torque, and there will not be any relationships between TC characteristics and leptin and adiponectin. During the measurement of MVC torque and twitch contractile properties of KE muscles, the subjects sat in a custom‐made dynamometric chair with the knee and hip angles equal to 90° and 100°, respectively. To assess the contractile properties of the KE muscles, electrically evoked isometric twitch was elicited by percutaneous electrical nerve stimulation. Serum leptin, adiponectin, IGF‐1, insulin‐like growth factor–binding protein‐3 (IGFBP‐3) and insulin were determined. There were a very few significant relationships between the measured muscle contractile parameters and fasting blood hormones. TC Pt correlated significantly with IGFBP‐3 (r = 0·652, P = 0·001) and insulin (r = 0·495, P = 0·007). In conclusion, this study suggests that only TC peak torque correlated positively with serum fasting IGFBP‐3 and insulin concentration. Adipocytokines leptin and adiponectin not correlated significantly with measured strength parameters in physically active postmenopausal women.