Caffeine vs. Carbohydrate Mouth Rinsing in Soccer

NCT ID: NCT06881316

Last Updated: 2025-03-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-02-10
• Study Completion Date: 2025-02-26

Brief Summary

The present study evaluated the influence of carbohydrate mouth-rinsing (CHO-MR), caffeine mouth-rinsing (CAF-MR), and control-substance mouth rinses on Loughborough soccer passing test (LSPT) performance. The study participants were involved in a randomized, double-blind, repeated-measures design that employed four sessions (familiarization, CHOMR, CAFMR, and CONT) over ten days at a testing facility. Participants took part in six test sessions 72 hours apart. In the CHO group, 6% w/v glucose solution was used. In the CAFF group, 6% w/v glucose solution was used. CONT group, only exercise was performed without any condition.

Detailed Description

Participants were involved in a randomized, double-blind, repeated-measures design that employed four sessions (familiarization, LSPTCHO, LSPTCAFF, and LSPTCONT) over ten days at a testing facility. The initial session was an orientation, allowing participants to acclimate to the LSPT protocol and provide written informed consent. This session used water as a mouth rinse. Anthropometric data were also collected. Before the LSPT, participants completed 15-minute standardized warm-up sections, including jogging, sprinting, and integrating soccer-specific actions. The participants were asked to complete the LSPT at any time. During the tests, participants were blinded to the test scores. The following three sessions were test trials conducted between 15.00 h and 17.00 h at 32°C and 40% humidity. The participants performed the LSPT 72 h apart, LSPTCHO (6% w/v glucose solution), LSPTCAFF (1.2% w/v caffeine solution), and LSPTCONT conditions. Caffeine and CHO solutions were prepared in an equivalent saccharin base to ensure indistinguishability within the Falcon Sterile Tube and agitated for 30 seconds on a vortex mixer. Participants were instructed to avoid intense activity 24 hours before testing, observe a 2-hour fast before sessions, and abstain from caffeinated products on test days. All the test sessions were performed at 32°C and 40% humidity.

Conditions

Performance; Soccer; Caffeine and Carbohydrate; Cognitive Function; Technical Skill

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

Caffeine Mouth Rinse Protocol (CAF-MR)

Caffeine solutions (1.2% w/v caffeine solution) were prepared in an equivalent saccharin base to ensure indistinguishability within the Falcon Sterile Tube and agitated for 30 seconds on a vortex mixer. Participants were instructed to avoid intense activity 24 hours before testing, observe a 2-hour fast before sessions, and abstain from caffeinated products on test days. The following three sessions were test trials conducted between 15.00 h and 17.00 h at 32°C and 40% humidity.

Group Type: EXPERIMENTAL

Caffeine

Intervention Type: OTHER

Participants' solutions were prepared in separate Falcon Sterile Tubes: LSPTCAFF (1.2% w/v caffeine solution, Nature's Supreme). An MRI was performed before the LSPT. The solution was sweetened with non-caloric artificial sweeteners consisting of sucralose. The caffeine solution was prepared in an equivalent saccharin base and shaken for 30 seconds in a vortex mixer to ensure distinguishability. Participants swished the solution in their mouth for 10 seconds before LSPT and then emptied it back into the container to be weighed again. To ensure that the solutions were not swallowed, the containers were measured before and after all MRs using a full precision balance (Etekcity, USA) accurate to 1 g/0.04 oz.

CHO Mouth Rinse Protocol (CHO-MR)

CHO solutions (6% w/v glucose solution) were prepared in an equivalent saccharin base to ensure indistinguishability within the Falcon Sterile Tube and agitated for 30 seconds on a vortex mixer. Participants were instructed to avoid intense activity 24 hours before testing, observe a 2- hour fast before sessions, and abstain from caffeinated products on test days. The following three sessions were test trials conducted between 15.00 h and 17.00 h at 32°C and 40% humidity.

Group Type: EXPERIMENTAL

CHO

Intervention Type: OTHER

Participants' solutions were prepared in separate Falcon Sterile Tubes: LSPTCHO (6% w/ v glucose solution, Protein Ocean, Turkey) An MRI was performed prior to LSPT. The solution was sweetened with non-caloric artificial sweeteners consisting of sucralose. The CHO solution was prepared in an equivalent saccharin base and shaken for 30 seconds in a vortex mixer to ensure distinguishability. Participants swished the solution in their mouth for 10 seconds before LSPT and then emptied it back into the container to be weighed again. To ensure that the solutions were not swallowed, the containers were measured before and after all MRs using a full precision balance (Etekcity, USA) accurate to 1 g/0.04 oz.

Control Condition

Only exercise was performed without any condition.

Group Type: EXPERIMENTAL

Control

Intervention Type: OTHER

For the control condition, no supplements were taken and only exercise was performed.

Interventions

Caffeine

Participants' solutions were prepared in separate Falcon Sterile Tubes: LSPTCAFF (1.2% w/v caffeine solution, Nature's Supreme). An MRI was performed before the LSPT. The solution was sweetened with non-caloric artificial sweeteners consisting of sucralose. The caffeine solution was prepared in an equivalent saccharin base and shaken for 30 seconds in a vortex mixer to ensure distinguishability. Participants swished the solution in their mouth for 10 seconds before LSPT and then emptied it back into the container to be weighed again. To ensure that the solutions were not swallowed, the containers were measured before and after all MRs using a full precision balance (Etekcity, USA) accurate to 1 g/0.04 oz.

Intervention Type: OTHER

CHO

Participants' solutions were prepared in separate Falcon Sterile Tubes: LSPTCHO (6% w/ v glucose solution, Protein Ocean, Turkey) An MRI was performed prior to LSPT. The solution was sweetened with non-caloric artificial sweeteners consisting of sucralose. The CHO solution was prepared in an equivalent saccharin base and shaken for 30 seconds in a vortex mixer to ensure distinguishability. Participants swished the solution in their mouth for 10 seconds before LSPT and then emptied it back into the container to be weighed again. To ensure that the solutions were not swallowed, the containers were measured before and after all MRs using a full precision balance (Etekcity, USA) accurate to 1 g/0.04 oz.

Intervention Type: OTHER

Control

For the control condition, no supplements were taken and only exercise was performed.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Being healthy
• Male soccer players
• Willing to maintain the intervention for all sessions

Exclusion Criteria

• Being under 14 years old
• Having a chronic disease
• Contraindication for caffeine mouth-rinsing (CAF-MR)
• Contraindication for carbohydrate mouth-rinsing (CHO-MR)
• Contraindications for exercise

• Minimum Eligible Age: 14 Years
• Maximum Eligible Age: 16 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

Tokat Gaziosmanpasa University

OTHER

Sponsor Role: lead

Responsible Party

Ersan Arslan

Prof. Dr.

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Ersan Arslan, Doctorate

Role: STUDY_CHAIR

+905325452848

Locations

Tokat Gaziosmanpasa Universty

Tokat Province, Turkey, Turkey (Türkiye)

Countries

Turkey (Türkiye)

References

Soylu Y, Ramazanoglu F, Arslan E, Clemente FM. Effects of mental fatigue on the psychophysiological responses, kinematic profiles, and technical performance in different small-sided soccer games. Biol Sport. 2022 Oct;39(4):965-972. doi: 10.5114/biolsport.2022.110746. Epub 2021 Dec 30.

Reference Type: BACKGROUND

PMID: 36247954 (View on PubMed)

Soylu Y, Chmura P, Arslan E, Kilit B. The Effects of Carbohydrate Mouth Rinse on Psychophysiological Responses and Kinematic Profiles in Intermittent and Continuous Small-Sided Games in Adolescent Soccer Players: A Randomized, Double-Blinded, Placebo-Controlled, and Crossover Trial. Nutrients. 2024 Nov 15;16(22):3910. doi: 10.3390/nu16223910.

Reference Type: BACKGROUND

PMID: 39599695 (View on PubMed)

Other Identifiers

UGaziosmanpasa-1

Identifier Type: -

Identifier Source: org_study_id