# Dietary habits and knee and shoulder injury incidence in adolescent male and female handball players: the Swedish Handball Cohort

## TL;DR

This study examines how dietary habits and menstrual function relate to knee and shoulder injuries in adolescent handball players in Sweden.

## Contribution

The study identifies specific dietary factors associated with injury risk in female adolescent handball players.

## Key findings

- Moderate-high nutritional quality and ≥2 unfavourable dietary habits are linked to higher knee/shoulder injury incidence in females.
- Poor meal timing shows a weak association with injury risk in females.
- No significant associations were found for males or menstrual dysfunction in females.

## Abstract

To assess the association between (1) dietary habits and knee/shoulder injury incidence in male and female adolescent handball players and (2) menstrual dysfunction and injury incidence in females.

This study is based on seasons 2020–2022 of the Swedish Handball Cohort including 1144 participants (1703 player seasons) free from a substantial knee and shoulder injury. Participants self-reported meal frequency, meal timing, nutritional intake and menstrual function (season 2022/2023) at baseline. Weekly follow-ups throughout the season assessed training and matches, and substantial knee/shoulder injuries. Cox regression analyses estimated a hazard rate ratio (HRR) with the first event of a knee/shoulder injury (combined), with minutes of handball training and matches as the timescale.

In females, adjusted analyses generated an HRR for knee/shoulder injuries of 1.46 (95% CI 1.08, 1.98) for moderate-high nutritional quality compared with low quality and an HRR of 1.38 (95% CI 1.02, 1.86) for ≥2 unfavourable dietary habits compared with 1 unfavourable dietary habit. For poor meal timing, adjusted analyses generated an HRR of 1.20 (95% CI 0.90, 1.61) compared with adequate timing in females. In males, adjusted analyses generated an HRR of 1.23 (95% CI 0.69, 2.17) for low meal frequency and an HRR of 0.83 (95% CI 0.60, 1.15) for poor meal timing.

In adolescent female handball players, moderate-high nutritional quality and ≥2 unfavourable dietary habits are associated with higher knee/shoulder injury incidence; whereas, no or unprecise associations were found for other dietary habits in females and males and for menstrual dysfunction in females.