Casein Supplementation: Pre-Sleep vs. Post-Exercise

NCT07170228 | Completed

• 2 other identifiers: GTU-2025-CASEIN01Ethics Committee -GTU-EC-2024
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized controlled trial aimed to investigate the effects of casein supplementation timing on post-exercise recovery and exercise performance in trained football players. Participants were allocated into three groups: pre-sleep casein ingestion, post-exercise casein ingestion, and control. The study compared the effects of pre-sleep and post-exercise casein intake on anaerobic performance, agility, and recovery markers following a standardized high-intensity resistance training session.

Conditions

Athletic Performance

Keywords

Casein Supplementation; Pre-Sleep Protein Intake; Post-Exercise Protein Intake; Muscle Recovery; Anaerobic Performance

Outcome Measures

Primary Outcomes (1)

• Peak Power (RAST Test)

  Peak power will be calculated using body mass and sprint times obtained during the RAST test to assess maximal anaerobic performance. Measurements will be taken at baseline and 24 hours post-training.

  Change from baseline (pre-test) to 24 hours post-training (post-test)

Secondary Outcomes (4)

• Mean Power (RAST Test)

  Change from baseline (pre-test) to 24 hours post-training (post-test)

• Fatigue Index (RAST Test)

  Change from baseline (pre-test) to 24 hours post-training (post-test)

• Countermovement Jump (CMJ) Height

  Change from baseline (pre-test) to 24 hours post-training (post-test)

• Illinois Agility Test Time

  Change from baseline (pre-test) to 24 hours post-training (post-test)

Study Arms (3)

Pre-Sleep Casein Ingestion Group

EXPERIMENTAL

Participants consumed 30 g of micellar casein dissolved in 300 mL of water 30-60 minutes before sleep following the standardized high-intensity resistance training session. Supplement intake was directly monitored by the research team to ensure compliance.

Dietary Supplement: Micellar Casein

Post-Exercise Casein Ingestion Group

EXPERIMENTAL

Participants consumed 30 g of micellar casein dissolved in 300 mL of water 10-15 minutes after completing the standardized high-intensity resistance training session. Supplement preparation and intake were supervised by the research team.

Dietary Supplement: Micellar Casein

Control Group

NO INTERVENTION

Participants completed the standardized high-intensity resistance training protocol but did not receive any supplementation.

Interventions

Micellar Casein DIETARY_SUPPLEMENT

Participants consumed 30 g of micellar casein powder dissolved in 300 mL of water. Supplement timing varied by group: Post-Exercise Casein Ingestion Group (PECIG): Taken 10-15 minutes after completing the standardized high-intensity resistance training session. Pre-Sleep Casein Ingestion Group (PSCIG): Taken 30-60 minutes before bedtime on the same day as the training session. The control group received no supplementation. All supplements were prepared and monitored by the research team to ensure dosage accuracy and participant compliance.

Post-Exercise Casein Ingestion Group; Pre-Sleep Casein Ingestion Group

Eligibility Criteria

• Age: 18 Years - 25 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male football players aged 18 to 25 years.
• At least three years of competitive soccer experience.
• Engaged in structured soccer training at least three times per week during the previous six months.
• Clearance to participate based on the Physical Activity Readiness Questionnaire (PAR-Q) (Thomas et al., 1992; Bredin et al., 2013).
• Provided written informed consent prior to participation.

You may not qualify if:

• Any musculoskeletal injury or surgery within the past six months.
• Reported milk or casein intolerance or allergy.
• Regular use of ergogenic supplements such as protein or creatine during the previous four weeks
• Medical conditions or limitations that could interfere with maximal exercise performance.
• Non-compliance with study procedures or training/testing protocols.

Sponsors & Collaborators

• Serdar Bayrakdaroğlu: lead

Study Sites (1)

Gumushane University, Faculty of Sport Sciences

Gümüşhane, Gümüşhane Province, 29100, Turkey (Türkiye)

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Outcome assessors were blinded to participant group assignments, while participants and investigators were not blinded due to the nature of the intervention.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Associate Professor, Principal Investigato

Model Details: Participants were randomized into three parallel groups: pre-sleep casein ingestion, post-exercise casein ingestion, or control, using stratified block randomization.

Study Record Dates

• First Submitted: September 5, 2025
• First Posted: September 12, 2025
• Study Start: March 10, 2025
• Primary Completion: March 14, 2025
• Study Completion: March 14, 2025
• Last Updated: September 12, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)