A Korean research team examined whether adolescents' physical strength has declined over time. They measured handgrip strength—a simple but reliable indicator of overall muscle power—in 4,867 teenagers aged 10 to 19 years using national health survey data collected between 2014 and 2022.
Handgrip strength is measured by squeezing a device called a dynamometer. It's useful because it's quick to assess, doesn't require special equipment, and reflects a person's general muscular fitness.
Teen strength has remained surprisingly steady over nine years
Contrary to concerns about declining youth fitness, the study found that adolescent handgrip strength stayed relatively stable across the nine-year period. While some fluctuations appeared in specific years—particularly a dip in 2016–2019 before rebounding in 2022—these variations were generally small. For example, some boys showed a drop of 1.7 to 4.1 kilograms during the weaker years, but recovered by 2022. Girls showed similar modest shifts of 1.6 to 2.6 kilograms during low years.
Importantly, not every age group or gender experienced these dips. Some teenagers showed no meaningful change across all nine years, suggesting the pattern wasn't universal.
Strength grows predictably from age 10 through the teen years
The research established clear benchmarks for what's normal at each age. The youngest teenagers (10–11 years old) had the lowest handgrip strength, and strength progressively increased as adolescents grew older. Boys consistently showed greater absolute strength than girls, which aligns with typical adolescent development patterns.
These reference values can help doctors and educators identify whether an individual teen's strength is typical for their age and sex—useful information if there are concerns about a specific child's fitness or development.
What the differences actually mean
The strength variations observed weren't dramatic. When researchers adjusted measurements to account for differences in height and body mass, the patterns became even less consistent. This suggests that any real decline in strength during those middle years was minimal and may partly reflect changes in body size rather than true loss of muscle power.
One limitation: this data comes from Korea only, so findings may not directly apply to Singapore or other Asian countries where living conditions, physical activity levels, and nutrition differ.
What this means for your teen's fitness
- Use these benchmarks: Korean adolescent strength reference values can serve as a rough guide to assess whether your teen's fitness is typical for their age, though individual variation is normal.
- Focus on consistency: Rather than worrying about generational decline, prioritise regular physical activity for your teen—strength naturally develops through movement and exercise.
- Track your own teen: If you're concerned about your child's strength or physical development, discuss it with their school doctor, who can compare them to age-appropriate benchmarks.