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Caffeinated Gum Use and Volleyball Performance

15 mei 2026 bijgewerkt door: Gülbin Rudarlı, Ege University

Acute Effects of Caffeinated Gum Use on Volleyball Performance: A Randomized, Placebo-Controlled Crossover Trial

This study examined the acute effects of caffeinated chewing gum on volleyball performance in trained female volleyball players. Caffeine is commonly used by athletes to improve performance, but less is known about whether caffeinated gum is useful during volleyball-specific activity.

Participants completed three testing sessions in a randomized crossover design. In one session, they chewed placebo gum. In another session, they chewed caffeinated gum containing a single 300 mg dose of caffeine. In the third session, they received the same total amount of caffeine as three separate 100 mg doses given at 30-minute intervals.

The study assessed volleyball-specific skill performance, including attack, block, and defense efficiency, during a volleyball-specific skill game. Vertical jump height, heart rate, perceived exertion, side effects, and condition guessing were also recorded.

Studie Overzicht

Gedetailleerde beschrijving

This randomized, placebo-controlled, crossover study investigated whether the pattern of caffeinated gum administration affects volleyball-specific performance in trained female volleyball players. Participants completed one familiarization session and three experimental sessions separated by one week. The experimental conditions were placebo gum, single-dose caffeinated gum, and partial-dose caffeinated gum.

In the single-dose condition, participants chewed three pieces of caffeinated gum containing a total of 300 mg caffeine for 5 minutes. In the partial-dose condition, participants chewed one piece of caffeinated gum containing 100 mg caffeine at three different time points, with 30-minute intervals between doses. In the placebo condition, participants chewed caffeine-free gum for 5 minutes.

Each testing session included volleyball-specific activities and a 30-minute volleyball-specific skill game. Attack, block, and defense efficiency were assessed using video recordings and Data Volley software. Vertical jump height was measured before and after the volleyball-specific activity. Heart rate was recorded during the session, and rating of perceived exertion was assessed before and after the session. Participants were also asked to report side effects and to guess which condition they had received after each session.

Studietype

Ingrijpend

Inschrijving (Werkelijk)

11

Fase

  • Niet toepasbaar

Contacten en locaties

In dit gedeelte vindt u de contactgegevens van degenen die het onderzoek uitvoeren en informatie over waar dit onderzoek wordt uitgevoerd.

Studie Locaties

    • Bornova
      • Izmir, Bornova, Turkije (Türkiye), 35040
        • Ege University, Faculty of Sport Sciences

Deelname Criteria

Onderzoekers zoeken naar mensen die aan een bepaalde beschrijving voldoen, de zogenaamde geschiktheidscriteria. Enkele voorbeelden van deze criteria zijn iemands algemene gezondheidstoestand of eerdere behandelingen.

Geschiktheidscriteria

Leeftijden die in aanmerking komen voor studie

  • Volwassen

Accepteert gezonde vrijwilligers

Ja

Beschrijving

Inclusion Criteria:

  • Female volleyball players aged 18 to 35 years.
  • Apparently healthy.
  • Daily caffeine intake ≤300 mg.
  • Minimum of 5 years of regular volleyball training experience.
  • Training for at least 120 minutes at least 3 days per week.
  • Competing in national or international volleyball matches.
  • Provided written informed consent before participation.

Exclusion Criteria:

  • Serious injury or trauma within the past 6 months that could affect volleyball performance.
  • Illness or inability to continue the study protocol during the research period.
  • Development of side effects during caffeinated gum administration that prevented continuation.
  • Regular alcohol or drug use that could affect the study outcomes.

Studie plan

Dit gedeelte bevat details van het studieplan, inclusief hoe de studie is opgezet en wat de studie meet.

Hoe is de studie opgezet?

Ontwerpdetails

  • Primair doel: Ander
  • Toewijzing: Gerandomiseerd
  • Interventioneel model: Crossover-opdracht
  • Masker: Dubbele

Wapens en interventies

Deelnemersgroep / Arm
Interventie / Behandeling
Experimenteel: Placebo, Single-Dose Caffeine, Partial-Dose Caffeine Arm Type: Experimental
Participants received placebo gum in the first session, single-dose caffeinated gum in the second session, and partial-dose caffeinated gum in the third session. Sessions were separated by one week.
Participants chewed three pieces of caffeinated gum containing 100 mg caffeine per piece, providing a total dose of 300 mg caffeine. The gum was chewed for 5 minutes and then discarded.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants received three separate pieces of caffeinated gum containing 100 mg caffeine per piece. One piece was chewed for 5 minutes at each administration time point, with doses given at 30-minute intervals, providing a total dose of 300 mg caffeine.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants chewed caffeine-free placebo gum for 5 minutes. The placebo gum was selected to be similar in shape and color to the caffeinated gum.
Andere namen:
  • Caffeine-free gum
  • Placebo chewing gum
Experimenteel: Placebo, Partial-Dose Caffeine, Single-Dose Caffeine
Participants received placebo gum in the first session, partial-dose caffeinated gum in the second session, and single-dose caffeinated gum in the third session. Sessions were separated by one week.
Participants chewed three pieces of caffeinated gum containing 100 mg caffeine per piece, providing a total dose of 300 mg caffeine. The gum was chewed for 5 minutes and then discarded.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants received three separate pieces of caffeinated gum containing 100 mg caffeine per piece. One piece was chewed for 5 minutes at each administration time point, with doses given at 30-minute intervals, providing a total dose of 300 mg caffeine.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants chewed caffeine-free placebo gum for 5 minutes. The placebo gum was selected to be similar in shape and color to the caffeinated gum.
Andere namen:
  • Caffeine-free gum
  • Placebo chewing gum
Experimenteel: Single-Dose Caffeine, Placebo, Partial-Dose Caffeine
Participants received single-dose caffeinated gum in the first session, placebo gum in the second session, and partial-dose caffeinated gum in the third session. Sessions were separated by one week.
Participants chewed three pieces of caffeinated gum containing 100 mg caffeine per piece, providing a total dose of 300 mg caffeine. The gum was chewed for 5 minutes and then discarded.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants received three separate pieces of caffeinated gum containing 100 mg caffeine per piece. One piece was chewed for 5 minutes at each administration time point, with doses given at 30-minute intervals, providing a total dose of 300 mg caffeine.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants chewed caffeine-free placebo gum for 5 minutes. The placebo gum was selected to be similar in shape and color to the caffeinated gum.
Andere namen:
  • Caffeine-free gum
  • Placebo chewing gum
Experimenteel: Single-Dose Caffeine, Partial-Dose Caffeine, Placebo
Participants received single-dose caffeinated gum in the first session, partial-dose caffeinated gum in the second session, and placebo gum in the third session. Sessions were separated by one week.
Participants chewed three pieces of caffeinated gum containing 100 mg caffeine per piece, providing a total dose of 300 mg caffeine. The gum was chewed for 5 minutes and then discarded.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants received three separate pieces of caffeinated gum containing 100 mg caffeine per piece. One piece was chewed for 5 minutes at each administration time point, with doses given at 30-minute intervals, providing a total dose of 300 mg caffeine.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants chewed caffeine-free placebo gum for 5 minutes. The placebo gum was selected to be similar in shape and color to the caffeinated gum.
Andere namen:
  • Caffeine-free gum
  • Placebo chewing gum
Experimenteel: Partial-Dose Caffeine, Placebo, Single-Dose Caffeine
Participants received partial-dose caffeinated gum in the first session, placebo gum in the second session, and single-dose caffeinated gum in the third session. Sessions were separated by one week.
Participants chewed three pieces of caffeinated gum containing 100 mg caffeine per piece, providing a total dose of 300 mg caffeine. The gum was chewed for 5 minutes and then discarded.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants received three separate pieces of caffeinated gum containing 100 mg caffeine per piece. One piece was chewed for 5 minutes at each administration time point, with doses given at 30-minute intervals, providing a total dose of 300 mg caffeine.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants chewed caffeine-free placebo gum for 5 minutes. The placebo gum was selected to be similar in shape and color to the caffeinated gum.
Andere namen:
  • Caffeine-free gum
  • Placebo chewing gum
Experimenteel: Partial-Dose Caffeine, Single-Dose Caffeine, Placebo
Participants received partial-dose caffeinated gum in the first session, single-dose caffeinated gum in the second session, and placebo gum in the third session. Sessions were separated by one week.
Participants chewed three pieces of caffeinated gum containing 100 mg caffeine per piece, providing a total dose of 300 mg caffeine. The gum was chewed for 5 minutes and then discarded.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants received three separate pieces of caffeinated gum containing 100 mg caffeine per piece. One piece was chewed for 5 minutes at each administration time point, with doses given at 30-minute intervals, providing a total dose of 300 mg caffeine.
Andere namen:
  • Caffeine gum
  • Caffeinated chewing gum
Participants chewed caffeine-free placebo gum for 5 minutes. The placebo gum was selected to be similar in shape and color to the caffeinated gum.
Andere namen:
  • Caffeine-free gum
  • Placebo chewing gum

Wat meet het onderzoek?

Primaire uitkomstmaten

Uitkomstmaat
Maatregel Beschrijving
Tijdsspanne
Attack efficiency
Tijdsspanne: During the 30-minute volleyball-specific skill game in each experimental trial
Attack efficiency was assessed during a 30-minute volleyball-specific skill game using video recordings and Data Volley software. Values were expressed as percentages.
During the 30-minute volleyball-specific skill game in each experimental trial
Block efficiency
Tijdsspanne: During the 30-minute volleyball-specific skill game in each experimental trial
Block efficiency was assessed during a 30-minute volleyball-specific skill game using video recordings and Data Volley software. Values were expressed as percentages.
During the 30-minute volleyball-specific skill game in each experimental trial
Defense efficiency
Tijdsspanne: During the 30-minute volleyball-specific skill game in each experimental trial
Defense efficiency was assessed during a 30-minute volleyball-specific skill game using video recordings and Data Volley software. Values were expressed as percentages.
During the 30-minute volleyball-specific skill game in each experimental trial

Secundaire uitkomstmaten

Uitkomstmaat
Maatregel Beschrijving
Tijdsspanne
Change in vertical jump height
Tijdsspanne: From immediately before to immediately after each experimental trial
Vertical jump height was measured before and after each experimental testing session using a photoelectric cell system. Values were expressed in centimeters.
From immediately before to immediately after each experimental trial
Heart rate
Tijdsspanne: Continuously during each experimental trial
Heart rate was recorded during each experimental testing session using a telemetric heart rate monitoring system. Values were expressed as beats per minute.
Continuously during each experimental trial
Change in rating of perceived exertion
Tijdsspanne: From immediately before to immediately after each experimental trial
Rating of perceived exertion was assessed before and after each experimental testing session using a 0-10 Borg scale.
From immediately before to immediately after each experimental trial

Andere uitkomstmaten

Uitkomstmaat
Maatregel Beschrijving
Tijdsspanne
Side effects
Tijdsspanne: Immediately after each experimental trial
Participants were asked after each experimental testing session whether they experienced any side effects or discomfort related to the gum intervention. Reported responses were recorded descriptively.
Immediately after each experimental trial

Medewerkers en onderzoekers

Hier vindt u mensen en organisaties die betrokken zijn bij dit onderzoek.

Sponsor

Studie record data

Deze datums volgen de voortgang van het onderzoeksdossier en de samenvatting van de ingediende resultaten bij ClinicalTrials.gov. Studieverslagen en gerapporteerde resultaten worden beoordeeld door de National Library of Medicine (NLM) om er zeker van te zijn dat ze voldoen aan specifieke kwaliteitscontrolenormen voordat ze op de openbare website worden geplaatst.

Bestudeer belangrijke data

Studie start (Werkelijk)

5 augustus 2025

Primaire voltooiing (Werkelijk)

23 april 2026

Studie voltooiing (Werkelijk)

23 april 2026

Studieregistratiedata

Eerst ingediend

11 mei 2026

Eerst ingediend dat voldeed aan de QC-criteria

15 mei 2026

Eerst geplaatst (Werkelijk)

19 mei 2026

Updates van studierecords

Laatste update geplaatst (Werkelijk)

19 mei 2026

Laatste update ingediend die voldeed aan QC-criteria

15 mei 2026

Laatst geverifieerd

1 mei 2026

Meer informatie

Termen gerelateerd aan deze studie

Andere studie-ID-nummers

  • EGE-25-9.1T-28

Plan Individuele Deelnemersgegevens (IPD)

Bent u van plan om gegevens van individuele deelnemers (IPD) te delen?

NEE

Beschrijving IPD-plan

Individual participant data will not be shared because the dataset contains participant-level performance and physiological data from a small group of elite female volleyball players, which may increase the risk of participant identification.

Informatie over medicijnen en apparaten, studiedocumenten

Bestudeert een door de Amerikaanse FDA gereguleerd geneesmiddel

Nee

Bestudeert een door de Amerikaanse FDA gereguleerd apparaatproduct

Nee

Deze informatie is zonder wijzigingen rechtstreeks van de website clinicaltrials.gov gehaald. Als u verzoeken heeft om uw onderzoeksgegevens te wijzigen, te verwijderen of bij te werken, neem dan contact op met register@clinicaltrials.gov. Zodra er een wijziging wordt doorgevoerd op clinicaltrials.gov, wordt deze ook automatisch bijgewerkt op onze website .

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