# Protein-rich food intake frequency score and muscle mass, strength, muscle-specific strength or physical performance in Japanese older women: a cross-sectional study

## TL;DR

This study examines how protein-rich food intake relates to muscle health in older Japanese women.

## Contribution

It introduces a protein-rich food frequency score and evaluates its association with muscle mass and physical performance.

## Key findings

- Higher protein-rich food intake scores correlate with better muscle mass and strength in older women.
- No direct link was found between protein intake and muscle-specific strength.
- The Take 10-FFS is associated with improved physical performance outcomes.

## Abstract

Sarcopenia, defined as age-related muscle loss, has significant implications on the physical performance and health of older adults. An adequate dietary protein intake plays a crucial role in maintaining muscle mass and function. In Japan, the “Take 10!” assessment method, focusing on 10 food groups with an emphasis on 5 protein-rich foods, has been used for older adults. This study aimed to explore the relationship between the protein-rich food intake frequency score (PFFS) and muscle mass, strength, muscle-specific strength, and physical performance in older Japanese women.

This study included 309 Japanese women aged 65–92 years. The appendicular skeletal muscle mass and skeletal muscle index were assessed. Hand grip strength and knee extension strength were measured, and muscle-specific strength was calculated. Chair stand test, shuttle stamina walk test, 10-m walk test, and timed up-and-go test were conducted. The Take 10 food frequency score (Take10-FFS) and PFFS were obtained. A one-way analysis of covariance was conducted, adjusted for age, percent body fat, exercise habits, smoking habits, alcohol habits, preexisting conditions, polypharmacy, fall incidence within 1 year, subjective economic status, and years of education.

Higher Take 10-FFS and PFFS were associated with better muscle mass, strength, and physical performance (P < 0.05), emphasizing the importance of protein intake in preventing sarcopenia. However, no direct association was found between PFFS and muscle-specific strength (P > 0.05). This underscores the complexity of the factors influencing muscle-specific strength.