# Secular trend in height and associated factors among adolescents in Florianópolis, Santa Catarina, Brazil, between 2007 and 2017/2018

## TL;DR

This study found that adolescents in Florianópolis grew taller over a decade, with factors like fat-free mass and physical activity influencing height.

## Contribution

The study identifies specific factors influencing height trends in Brazilian adolescents over a ten-year period.

## Key findings

- Adolescents showed an average height increase of 3.5 cm over ten years.
- Fat-free mass positively predicts height, while body fat negatively predicts height in both sexes.
- Physical activity negatively predicts height in boys.

## Abstract

To assess the secular trend in height among adolescents in Florianópolis between 2007 and 2017/2018, and identify factors associated with height by sex.

The sample included 664 adolescents from public schools in 2007 and 1,008 in 2017/2018. Height was the dependent variable, with age, economic status, sexual maturity, physical activity, body fat (skinfold thickness), and fat-free mass as independent variables. Analysis of covariance evaluated the secular trend, and multiple linear regression identified associated factors.

There was a positive secular trend in height in both sexes when comparing the two surveys, with average increases of 3.5 cm in both sexes. Fat-free mass was a positive predictor and body fat was a negative predictor of height in both sexes. Additionally, physical activity emerged as a negative predictor of height specifically in boys.

The research revealed a positive secular trend in the height of adolescents in Florianópolis. Fat-free mass contributes positively to gains in height, whereas body fat provides a negative contribution.