CClinicalTrials.gg
Status unknownNCT04290819Updated Mar 2, 2020

Effect of Creatine and Caffeine on Muscle Performance

An interventional study of Creatine Monohydrate and Creatine Monohydrate and Caffeine in Performance Enhancing Product Use, sponsored by University of Regina. Status unknown at 1 site in Canada. Open to participants aged 18 Years to 39 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2020-03-02.

Sponsored by University of Regina · Not applicable, Interventional, and Basic science

The sponsor has not verified this record recently (last verified Feb 2020), so the status shown — last known as Recruiting — may be out of date.

From the registry’s dates

  • Registered 10 months after the study started (first participant enrolled Feb 2019, registered Jan 2020).
Phase
Not applicable
Study type
Interventional
Enrollment
36
Allocation
Randomized
Ages
18 Years to 39 Years
Sex
All
01

Study summary

To determine if creatine and caffeine can be co-supplemented without inhibiting the effects of creatine.

Read the detailed description

Creatine and caffeine are among the most popular ergogenic aids used by exercising individuals. Creatine supplementation during resistance training has been shown to increase muscle mass and muscle performance (i.e. strength, endurance), possibly by influencing high-energy phosphate metabolism, muscle protein kinetics, and inflammation. Caffeine ingestion has been shown to increase muscle performance, primarily by influencing adenosine receptor activity, muscle protein kinetics, phosphodiesterase, and excitation-coupling. Previous research investigating the combined effects of creatine and caffeine has produced mixed results, with some showing a beneficial effect on short-term anaerobic type activities, while other report no effect. Despite the potential beneficial effects of creatine and caffeine separately, no study has compared the combined effects of creatine and caffeine during resistance training. Therefore, the purpose of this thesis is to determine the effects of creatine and caffeine co-supplementation during resistance training on muscle mass and muscle performance in trained young adults.

The study will be a double-blind, repeated measures design. In order to minimize group differences, participants will be matched according to age and weight and be randomized on a 1:1:1:1 basis to one of four groups: Creatine + Caffeine (CR-CAF; 0.1 g/kg of creatine monohydrate powder + 3 mg/kg of caffeine [micronized powder]); Creatine (CR; 0.1 g/kg of creatine monohydrate powder + 3 mg/kg of caffeine placebo [micronized cellulose powder]), Caffeine (CAF; 3 mg/kg of caffeine + 0.1 g/kg of creatine monohydrate placebo [maltodextrin]) or placebo (PLA; 0.1g/kg creatine monohydrate placebo + 3 mg/kg of caffeine placebo). An individual, blinded to supplement and group allocation, will be responsible for the preparation of study kits. Each study kit will contain the participants supplement for the duration of the study, detailed supplementation instructions, measuring spoons, supplementation compliance log, daily caffeine consumption log and a resistance training log. Supplement powders will be similar in energy content, color, taste, texture, and appearance. The creatine dosage of 0.1 g/kg has previously been shown to be effective for increasing muscle mass and muscle performance. The caffeine dosage of 3 mg/kg has been shown to increase muscle performance. Participants will be instructed to refrain from additional caffeine sources ≥ 3 hour prior to consuming their supplement so that a valid estimate regarding the effects of caffeine supplementation on muscle can be made. On training days, participants will mix their supplement powder in water and consume the solution 60 minutes prior to exercise. Sixty minutes was chosen because this is the approximate time it takes for peak plasma caffeine concentrations to occur after caffeine ingestion and pre-exercise creatine supplementation has a beneficial effect on muscle performance.

Participants will follow the same periodized, resistance training program for 6 weeks. The program will consist of three sets of 6, 8, 10 repetitions to muscle fatigue in order. Resistance training will start on the first day of supplementation and will consist of a split routine involving whole body musculature. Day 1 will involve chest and biceps musculature and include the following exercises in order: machine-based chest press, free weight incline bench press or dumbbell press, free-weight flat dumbbell press, machine-based pec-dec, free-weight standing barbell curl, free-weight alternate arm dumbbell curl and machine-based preacher curl. Day 2 will involve leg and core musculature and include the following exercises in order: free-weight squat, machine-based leg press, machine-based leg extension, machine-based leg curl, machine-based calf raise, and machine-based weighted abdominal crunches. Day 3 will serve as a rest day from training. Day 4 will involve back and triceps musculature and include the following exercises in order: body weight or weight-assisted chin-ups, machine-based seated row, machine-based lat pull-down, free-weight alternate dumb-bell row, free-weight close-grip bench press, machine-based cable triceps bar extension, and machine-based cable triceps rope extension. Day 5 will involve shoulder and core musculature and include the following exercises in order: free-weight dumbbell press, free-weight upright row, free-weight shrugs, free-weight or machine based lateral deltoid flys, free weight or machine-based rear deltoid flys and machine-based weighted abdominal crunches. Day 6 will serve as a rest day from training. This cycle will be repeated for 6 weeks. Participants will maintain training logs to ensure adherence and compliance to the study and to determine total training volume (load x repetitions x sets).

02

Conditions studied

  • Performance Enhancing Product Use

Keywords

  • Muscle Endurance
  • Strength
  • Hypertrophy
  • Resistance Training
  • Creatine
  • Caffeine
03

In context

Lead sponsor

University of Regina is the lead sponsor of 56 studies on the registry; 22 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 39 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Male or Female ages 18-39
  • Resistance training for minimum of 6 months 3/week.

Exclusion criteria

Exclusion Criteria:

  • Creatine supplementation within last 3 months
  • Taking medications that affect muscle biology
  • Have a disease that affects muscle biology
  • Pre existing liver or kidney abnormalities
  • Plan to travel for greater then 1 week during the study where you have NO access to fitness facility.
  • Fail Par-Q and are unable to receive doctors clearance
05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Factorial assignment
Masking
Double (Participant, Investigator)
Enrollment
36 participants (estimated)

Study arms

  • Experimental
    Resistance Training with Creatine Monohydrate

    Participants will go through a 6 week resistance training program (unsupervised), at the facility of their choice. They will be given a program to follow with a 2 day on one day rest split routine as follows: Chest and biceps, legs and core, rest, back and triceps, shoulders and core, rest. This cycle will repeat for the 6 week program.

    Dietary Supplement: Creatine Monohydrate

  • Experimental
    Resistance Training with Caffeine

    Participants will go through a 6 week resistance training program (unsupervised), at the facility of their choice. They will be given a program to follow with a 2 day on one day rest split routine as follows: Chest and biceps, legs and core, rest, back and triceps, shoulders and core, rest. This cycle will repeat for the 6 week program.

    Dietary Supplement: Caffeine

  • Experimental
    Resistance Training with Caffeine and Creatine Monohydrate

    Participants will go through a 6 week resistance training program (unsupervised), at the facility of their choice. They will be given a program to follow with a 2 day on one day rest split routine as follows: Chest and biceps, legs and core, rest, back and triceps, shoulders and core, rest. This cycle will repeat for the 6 week program.

    Dietary Supplement: Creatine Monohydrate and Caffeine

  • Placebo comparator
    Resistance Training with Placebo

    Participants will go through a 6 week resistance training program (unsupervised), at the facility of their choice. They will be given a program to follow with a 2 day on one day rest split routine as follows: Chest and biceps, legs and core, rest, back and triceps, shoulders and core, rest. This cycle will repeat for the 6 week program.

    Dietary Supplement: Placebo

Interventions

  • Dietary supplementCreatine Monohydrate

    0.1g/kg of body weight (pre measured creatine) and 3mg/kg of body weight (pre measured micronized cellulose powder-caffeine placebo) self administered 1 hr prior to working out mixed in water.

  • Dietary supplementCreatine Monohydrate and Caffeine

    0.1g/kg body weight (pre measured creatine) and 3mg/kg body weight (pre measured caffeine) self administered 1hr prior to working out mixed in water.

  • Dietary supplementCaffeine

    3mg/kg of body weight (pre measured caffeine) and 0.1g/kg of bodyweight (pre measured maltodextrin- creatine placebo) self administered 1 hr prior to working out mixed in water.

  • Dietary supplementPlacebo

    0.1g/kg of body weight (pre measured maltodextrin) and 3mg/kg of body weight (pre measured micronized cellulose powder) self administered 1 hr prior to working out mixed in water.

06

What researchers measure

Primary outcomes

  1. Muscle strength using a standard plate loaded leg press and chest press machine

    1-Rep max for leg press and chest press.

    Time frame: 6 weeks

  2. Hypertrophy

    Ultrasound of biceps, triceps, quads and hamstrings. Size in cm of each muscle site.

    Time frame: 6 weeks

  3. Muscle endurance using a standard plate loaded leg press and chest press machine

    Reps to fatigue at 50% 1-Rep Max.

    Time frame: 6 weeks

  4. Body Composition using a Bod Pod

    Test used to determine fat mass and lean tissue within a subject. Gives the fat % and the remainder is considered everything else. Since bone and organ wont really change over 6 weeks, all changes are considered to be lean tissue changes.

    Time frame: 6 weeks

Secondary outcomes

  1. Fatigue Scale (Generic)

    Assessed using fatigue scale (1-10) after each workout. The higher the number, the more the participant is fatigued

    Time frame: 6 weeks

  2. Rating of perceived exertion (Generic)

    Modified to encompass entire training day. 1-10 scale as to how hard that particular workout was. The higher the number, the harder the workout felt to the participant.

    Time frame: 6 weeks

07

Study locations

1 of 1 sites recruiting
  • University of Regina
    Regina, Saskatchewan S4S4H4, Canada
    Recruiting
08

References and documents

Publications

  • Trexler ET, Smith-Ryan AE. Creatine and Caffeine: Considerations for Concurrent Supplementation. Int J Sport Nutr Exerc Metab. 2015 Dec;25(6):607-23. doi: 10.1123/ijsnem.2014-0193. PubMed 26219105 ↗
  • Candow DG, Chilibeck PD. Timing of creatine or protein supplementation and resistance training in the elderly. Appl Physiol Nutr Metab. 2008 Feb;33(1):184-90. doi: 10.1139/H07-139. PubMed 18347671 ↗
  • Chilibeck PD, Kaviani M, Candow DG, Zello GA. Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: a meta-analysis. Open Access J Sports Med. 2017 Nov 2;8:213-226. doi: 10.2147/OAJSM.S123529. eCollection 2017. PubMed 29138605 ↗
  • Grgic J. Caffeine ingestion enhances Wingate performance: a meta-analysis. Eur J Sport Sci. 2018 Mar;18(2):219-225. doi: 10.1080/17461391.2017.1394371. Epub 2017 Oct 31. PubMed 29087785 ↗
  • Kreider RB, Kalman DS, Antonio J, Ziegenfuss TN, Wildman R, Collins R, Candow DG, Kleiner SM, Almada AL, Lopez HL. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017 Jun 13;14:18. doi: 10.1186/s12970-017-0173-z. eCollection 2017. PubMed 28615996 ↗
  • Candow DG, Chilibeck PD, Forbes SC. Creatine supplementation and aging musculoskeletal health. Endocrine. 2014 Apr;45(3):354-61. doi: 10.1007/s12020-013-0070-4. Epub 2013 Nov 5. PubMed 24190049 ↗
  • Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med. 2001;31(11):785-807. doi: 10.2165/00007256-200131110-00002. PubMed 11583104 ↗
  • Gualano B, Rawson ES, Candow DG, Chilibeck PD. Creatine supplementation in the aging population: effects on skeletal muscle, bone and brain. Amino Acids. 2016 Aug;48(8):1793-805. doi: 10.1007/s00726-016-2239-7. Epub 2016 Apr 23. PubMed 27108136 ↗

Study documents

  • Informed consent form · Mar 20, 2019
  • Study protocol · Mar 20, 2019

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No — As of now there is no plan to share data of individual participants.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 2, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04290819
Lead sponsor
University of Regina
Responsible party
Sponsor
First posted
Mar 2, 2020
Start date
Feb 15, 2019
Primary completion
May 31, 2020 (estimated)
Completion
Sep 1, 2020 (estimated)
Last update
Mar 2, 2020

Study contacts

Darren G Candow, PhD
Contact
darren.candow@uregina.ca
209-0280 ext. 306
Avery R Pakulak, BKin
Contact
pakulaka@uregina.ca
216-2904 ext. 306
Darren G Candow, PhD
principal investigator · Assoicate Dean of Kinesiology

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is status unknown, as verified in Feb 2020. You cannot join it, but the record below documents what was studied.

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