Advances in paediatric strength assessment: changing our perspective on strength development

Area of Science:

• Pediatric Physiology
• Human Movement Science
• Growth and Development

Background:

• Limited understanding of age and sex-specific strength changes during childhood and adolescence.
• Existing data show consistency in lower limb strength development but highlight muscle action and joint specificity.

Purpose of the Study:

• To elucidate age and sex-associated changes in strength during childhood and adolescence.
• To identify key factors influencing strength development, including maturation, stature, body mass, and muscle moment arm.

Main Methods:

• Review of available studies on age and sex-associated strength changes.
• Analysis of factors influencing strength, including maturation, stature, body mass, and muscle cross-sectional area.
• Consideration of technological advancements in examining explanatory variables.

Main Results:

• Strength increases in both sexes until approximately 14 years, with girls plateauing and boys showing a spurt.
• Significant sex differences in strength emerge by 18 years, particularly in upper body strength.
• Stature and muscle moment arm are identified as crucial factors in strength development, potentially more so than muscle cross-sectional area or maturation alone.

Conclusions:

• Age-associated strength development is driven by growth and maturation, with distinct sex differences appearing in adolescence.
• Stature, peak height velocity, and muscle moment arm are critical determinants of strength gains.
• Further longitudinal studies utilizing advanced imaging techniques are needed to fully understand the complex interplay of neural, mechanical, and muscular factors.