Pre-Sleep Creatine Enhances Anaerobic Power in Recreationally Active Females (SleepCrM)

This study is a randomized, double-blind, placebo-controlled trial designed to examine the effects of pre-sleep creatine monohydrate supplementation on anaerobic performance and muscle damage markers in recreationally active females. Participants will be randomly assigned to receive either 5 grams of creatine monohydrate or a placebo 30 minutes before sleep for seven consecutive days. Anaerobic performance will be assessed using the Wingate Anaerobic Test, evaluating peak and average power output and fatigue index. Blood samples will be collected before and after the supplementation period to analyze markers of muscle damage, including creatine kinase and lactate dehydrogenase. This study aims to provide insight into the efficacy of short-term, time-specific creatine supplementation for enhancing performance and recovery.

Study Overview

• Status: Recruiting
• Conditions: Muscle Fatigue; Exercise Recovery; Anaerobic Performance; Sports Nutrition; Creatine Supplementation; Recreational Physical Activity; Female Athletes
• Intervention / Treatment: Dietary supplement: Creatine Monohydrate; Dietary supplement: Placebo (Maltodextrin)

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Morteza Jourkesh, PhD; Phone Number: +98 938 278 4093; Email: mjourkesh@iau.ac.ir
• Study Contact Backup: Name: Caglar Soylu, phD; Phone Number: +90 5078593595; Email: fztcaglar5187@gmail.com

Study Locations

• Iran, Islamic Republic of
  • East Azerbaijan
    • Shabestar, East Azerbaijan, Iran, Islamic Republic of, 5381637183
      • Recruiting
      • Islamic Azad University, Shabestar Branch
      • Contact: Morteza Jourkesh, PhD; Phone Number: +98 938 278 4093; Email: mjourkesh@iau.ac.ir

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Female, aged 18 to 25 years

Recreationally active (engaging in structured resistance training 3-4 times per week for the past 6 months)

Regular menstrual cycles (used for scheduling purposes)

Able and willing to provide informed consent

Agreement to maintain normal diet and training routines throughout the study

Exclusion Criteria:

History of musculoskeletal injury affecting lower or upper limbs within the past 6 months

Known allergy or intolerance to creatine or maltodextrin

Use of performance-enhancing substances or supplements within the last 30 days

Use of recovery modalities such as massage, cryotherapy, or compression garments during the study period

Current use of anti-inflammatory medication

Pregnancy or breastfeeding

Inability to comply with study protocol or scheduled assessments

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Creatine Monohydrate Supplementation; Participants will receive 5 grams of creatine monohydrate powder dissolved in water, flavored with a sugar-free agent, 30 minutes before sleep each night for 7 days.	Dietary supplement: Creatine Monohydrate; Participants will receive 5 grams of creatine monohydrate powder dissolved in water, flavored with a sugar-free agent, 30 minutes before sleep each night for 7 days.
Placebo Comparator: Placebo Supplementation; Participants will receive 5 grams of a placebo powder (maltodextrin), visually identical and similarly flavored to the creatine supplement, 30 minutes before sleep each night for 7 days.	Dietary supplement: Placebo (Maltodextrin); Visually identical placebo (maltodextrin powder, 5 g/day), flavored with a sugar-free agent, dissolved in water and consumed 30 minutes before sleep for 7 consecutive days.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Average Power Output (Watts) - 30-Second Wingate Test	Average anaerobic power output will be calculated across the 30-second Wingate cycling test.	Baseline and post-intervention (Day 0 and Day 7)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peak Power Output (Watts) - Wingate Test	Peak power output during the initial 5 seconds of the 30-second Wingate cycling test.	Baseline and post-intervention (Day 0 and Day 7)
Fatigue Index (%) - Wingate Test	Calculated as the percent drop in power from peak to minimum power output during the 30-second Wingate test, indicating fatigue rate.	Baseline and post-intervention (Day 0 and Day 7)
Serum Creatine Kinase (CK) Activity	Serum creatine kinase activity will be measured as a marker of muscle damage using a spectrophotometric assay.	Baseline and 24 hours post Wingate Test (Day 0 and Day 8)
Serum Lactate Dehydrogenase (LDH) Activity	Serum lactate dehydrogenase activity will be measured as an indicator of cell membrane permeability and muscle damage using spectrophotometry.	Baseline and 24 hours post Wingate Test (Day 0 and Day 8)

Collaborators and Investigators

• Sponsor: Ankara Yildirim Beyazıt University

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2025
• Primary Completion (Estimated): May 10, 2025
• Study Completion (Estimated): July 10, 2025

Study Registration Dates

• First Submitted: April 15, 2025
• First Submitted That Met QC Criteria: April 15, 2025
• First Posted (Actual): April 22, 2025

Study Record Updates

• Last Update Posted (Actual): April 22, 2025
• Last Update Submitted That Met QC Criteria: April 15, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Keywords: Resistance Training; Creatine Monohydrate; Creatine Kinase (CK); Anaerobic Power; Pre-Sleep Supplementation; Wingate Test; Muscle Damage Markers; Lactate Dehydrogenase (LDH); Female Exercise Performance; Nutritional Ergogenic Aid; Recovery Enhancement
• Additional Relevant MeSH Terms: Fatigue
• Other Study ID Numbers: 162593019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The individual participant data (IPD) will not be shared due to privacy concerns and the limited scope of this study. The study involves a small sample size, and data sharing could risk participant confidentiality. Additionally, there are currently no external collaborations or repositories arranged for data sharing.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No