Effect of Plant vs Animal Protein Supplementation on Body Composition in Youth Soccer Players

Summary

This prospective, single-blind, randomized controlled trial investigates the comparative effects of plant-based protein (soy and rice blend) versus animal-based protein (whey) supplementation on body composition parameters in elite male youth soccer players. Twenty-five players (ages 16-18.7 years) from Udinese Calcio's Primavera (U-19) category are randomized into three groups: Plant Protein Group (n=8), Animal Protein Group (n=9), and Placebo Group (n=8). The intervention consists of post-training protein supplementation (17g protein/dose) administered within 15-30 minutes after each training session over a 4-week microcycle during the competitive season. Body composition is assessed using a multi-compartmental model including anthropometry (ISAK protocol), bioelectrical impedance analysis (BIA), and dual-energy X-ray absorptiometry (DEXA).

Conditions

• Athletic Performance Enhancement
• Body Composition Optimization
• Nutritional Supplementation in Athletes

Interventions

DIETARY_SUPPLEMENT

Plant-Based Protein Supplement

Composition per dose: 330ml soy beverage (10.8g protein) + 22g plant protein powder (6.6g protein) = 17.4g total protein. Administered post-training (15-30 min after), prepared 8 hours before, stored at 4°C, supervised consumption verified by nutrition staff.

DIETARY_SUPPLEMENT

Placebo

Composition per dose: 200ml rice beverage (0.2g protein) + vanilla flavoring = 0.2g total protein. Administered post-training (15-30 min after), prepared 8 hours before, stored at 4°C, supervised consumption verified by nutrition staff. Identical appearance to active supplements to maintain blinding.

DIETARY_SUPPLEMENT

Animal-Based Protein Supplement (Whey)

Composition per dose: 200ml rice beverage (0.2g protein) + 22g neutral whey protein (12.0g protein) + 11g vanilla whey protein (5.1g protein) = 17.3g total protein. Administered post-training (15-30 min after), prepared 8 hours before, stored at 4°C, supervised consumption verified by nutrition staff.

Sponsors & Collaborators

• Universidad Europea de Madrid

  collaborator OTHER

• Universidad Pablo de Olavide

  collaborator OTHER

• Antonio Molina Lopez

  lead OTHER

Principal Investigators

• Antonio Blas Molina Lopez, Phd · CTS-595 Research Group, Centre for Research into Physical and Sporting Performance. Universidad Pablo de Olavide

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

16 Years

Max Age

19 Years

Sex

MALE

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-01-17

Primary Completion

2026-02-18

Completion

2026-03-30

Countries

• Italy

Study Locations