Effects of Caffeine Ingestion on Morning Cognitive and Muscle Repeated Sprint Performance in Males

NCT07466732 | Enrolling By Invitation Early Phase 1

• 1 other identifier: 251127LJMUSPSREC93
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

Athletes often compete in the morning when they are biologically weaker; normally in competition heats or quarterfinals to qualify for the finals scheduled in the evening. Some athletes may even choose to perform at submaximal levels in these qualifying rounds, especially when they are expected to perform multiple times in the same day (such as weightlifting at the Olympic Games). Gross muscular performance such as power output or force production is greater in the evening than the morning (\~3-14% variation). Similarly, time-trial performance and repeated sprint performance (RSP; a good measure of performance in team sport) is \~3 and 5 % greater in the evening than the morning. The reason for this daily variation in performance is attributed to central factors (such as the body clock), as well as motivational and peripheral factors, including higher core and muscle temperatures in the evening compared to the morning. The body clock located within the anterior hypothalamus consists of a group of neurons known as suprachiasmatic nuclei, which are responsible for controlling the rhythm of core temperature. This 'master clock' has an endogenous period (\~24.2 h) slightly longer than the 24-h solar day; therefore, must be entrained by time cues (zeitgebers) to remain in sync with the environment, of these the light-dark cycle is the most powerful in humans. The most efficient nutritional ergogenic is caffeine. Recently caffeine has been investigated to reduce the negative influence of diurnal variations on repeated-sprint ability test (10 × 6 s cycle sprints, with 30 s of rest) at 60 min after ingestion of either 5 mg·kg-1 or placebo. A recent study reported that caffeine supplementation did not prevent the reduction in performance in the morning. However, placebo effect can be 3-5% and hence the use of a No-pill condition would ensure that any placebo effect is accounted for and that the true potential effect of caffeine can be established. To the best of our knowledge, no study has yet investigated a) caffeine (300 mg), NoPill or Placebo (300 mg dextrose) effects on cognitive and physiological morning performance.

Conditions

Caffeine; Placebo - Control; No Pill

Keywords

Caffine; morning cognitive performance; morning repeated sprint performance

Outcome Measures

Primary Outcomes (7)

• Morning repeated sprint performance test

  Morning repeated sprint performance test (10 x 20 m with 30 s recovery) on a vulcanised surfaced runway. With time recorded at 5, 10, 15 and 20 m in seconds.

  From enrolment to last experimental session (~4 weeks)

• Morning repeated sprint performance test heart rate

  Morning repeated sprint performance test (10 x 20 m with 30 s recovery) on a vulcanised surfaced runway. With heart rate using a heart rate monitor recorded at the end of each sprint. Takes \~ 1 second.

  From familiarisation to the final experimental session (~4 weeks).

• Rating of perceived exertion every sprint

  Morning repeated sprint performance test (10 x 20 m with 30 s recovery) on a vulcanised surfaced runway. With ratine of perceived exertion recorded at the end of each sprint. Takes \~ 1 second. Measured on a 6 (no exertion) to 20 (maximal exertion) scale.

  From familiarisation to the final experimental session (~4 weeks)

• Blood lactate and glucose at the end of the 10 sprints

  Blood taken from the finger tip and analysed for lactate and glucose levels in mmols. Takes 10 s.

  From enrolment to last experimental session (4 weeks)

• Core body temperature

  Ear temperature taken at rest and after the warmup. Measured in degrees Celsius. Takes 3 seconds.

  From enrolment to last experimental session (4 weeks)

• Morning Rey Auditory Verbal Learning Test

  Rey Auditory Verbal Learning Test: The RAVLT is a neuropsychological assessment designed to evaluate verbal memory. The test is designed as a list-learning paradigm in which the volunteer hears a list of 15 nouns and is asked to recall as many words from the list as possible. The number correct and the number that were given by the participant but not on the list (intrusions) are noted. This process is re-peated 4 more times. The process is repeated but with a second interference list (List B) is presented in the same manner, and the participant is asked to recall as many words as possible from List B and scoring recorded. . After the interference trial, the participant is immediately asked to recall the words from List A, which they heard five times previously and the number of correct words and intrusions are recorded. RAVTL total number, number of dis-tractions and retention are recorded and analysed.

  From familiarisation to the final experimental session (~4 weeks)

• Morning Stroop word-colour interference test

  Stroop word-colour interference test. The participants were asked to read out their responses to words or colours for 45 s as quickly as possible and to leave no errors uncorrected. This was filmed and the number of errors and total amount completed was recorded and analysed. The first sheet had text (red, blue, yellow, black and green) in black ink (naming word test, W). The second sheet had blocks of colour corresponding to the text on the first sheet (naming colour test, C). With the third sheet, the participants had to read out the word (which was coloured differently to the word, e.g., the word was yellow and the colour red, referred to as the naming colour of word test, CW) and for the fourth sheet, the participants had to read out the colon (which was wrongly named, e.g., the colour was yellow but the word was red, referred to as the naming of word not colour test, WC). In this fourth sheet, the words were printed in the reverse order to the third sheet.

  From familiarisation to the final experimental session (~4 weeks)

Secondary Outcomes (13)

• Morning grip strength

  Time Frame: From enrolment to last experimental session (4 weeks)

• Vertical jump (Counter movement Jump and hands on hips - best of 3)

  From enrolment to last experimental session (4 weeks)]

• Witty Cognitive agility test 2x 90 s

  From enrolment to last experimental session (4 weeks)]

• Morning Trail Making Test time to completion in seconds (TMT; parts A and B)

  From enrolment to last experimental session (4 weeks)

• Morning profile of mood states questionnaire

  From familiarisation to the final experimental session (~4 weeks)

Study Arms (3)

Group 1

EXPERIMENTAL

1\) NoPill, 2) PLAC, 3) Caffeine (300 mg)

Drug: Caffeine; Other: Placabo; Other: No Pill

Group 2

EXPERIMENTAL

1\) PLAC, 22) Caffeine (300 mg) 3) NoPill

Drug: Caffeine; Other: Placabo; Other: No Pill

Group 3

EXPERIMENTAL

1\) Caffeine (300 mg) 2) NoPill, 3) PLAC

Drug: Caffeine; Other: Placabo; Other: No Pill

Interventions

Caffeine DRUG

300mg of of caffeine anhydrous in 3 capsules similar to PLACEBO in size and weight

Group 1; Group 2; Group 3

Placabo OTHER

3 capsules of PLACEBO similar to caffeine condition in size and weight

Group 1; Group 2; Group 3

No Pill OTHER

No capsules were given

Group 1; Group 2; Group 3

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy adults
• years old
• Injury-free
• ≥ 2 years of weight/strength training experience
• Not receiving any pharmacological treatment (including non-steroidal anti-inflammatory drugs, NSAIDs) throughout the study period
• Low habitual caffeine consumers (≤ 150mg per day)
• No preference to training regarding time-of-day

You may not qualify if:

• Depressed mood (from the Beck depression inventory)
• Poor sleep quality (a Pittsburgh sleep quality index global score \>5
• Recent shift work or travel across multiple time-zones
• 'Extreme' chronotype (assessed via the Composite Morningness Questionnaire
• Risk factors and/or symptoms of cardiovascular disease.
• Page 9 of 11 - • Minimal knowledge of the effects of time-of-day or time-since-sleep on human performance

Sponsors & Collaborators

• Liverpool John Moores University: lead

Study Sites (1)

Tom Reilly Building (LJMU)

Liverpool, Merseyside, L3 3AF, United Kingdom

Location

Related Publications (4)

• Walsh NP, Halson SL, Sargent C, Roach GD, Nedelec M, Gupta L, Leeder J, Fullagar HH, Coutts AJ, Edwards BJ, Pullinger SA, Robertson CM, Burniston JG, Lastella M, Le Meur Y, Hausswirth C, Bender AM, Grandner MA, Samuels CH. Sleep and the athlete: narrative review and 2021 expert consensus recommendations. Br J Sports Med. 2020 Nov 3:bjsports-2020-102025. doi: 10.1136/bjsports-2020-102025. Online ahead of print.

  PMID: 33144349 BACKGROUND

• Drust B, Waterhouse J, Atkinson G, Edwards B, Reilly T. Circadian rhythms in sports performance--an update. Chronobiol Int. 2005;22(1):21-44. doi: 10.1081/cbi-200041039.

  PMID: 15865319 BACKGROUND

• Munnilari M, Bommasamudram T, Easow J, Tod D, Varamenti E, Edwards BJ, Ravindrakumar A, Gallagher C, Pullinger SA. Diurnal variation in variables related to cognitive performance: a systematic review. Sleep Breath. 2024 Mar;28(1):495-510. doi: 10.1007/s11325-023-02895-0. Epub 2023 Aug 17.

  PMID: 37589927 BACKGROUND

• Mitchell PJ, Redman JR. Effects of caffeine, time of day and user history on study-related performance. Psychopharmacology (Berl). 1992;109(1-2):121-6. doi: 10.1007/BF02245489.

  PMID: 1365645 BACKGROUND

MeSH Terms

Interventions

Caffeine

Intervention Hierarchy (Ancestors)

Xanthines; Alkaloids; Heterocyclic Compounds; Purinones; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Study Officials

• Ben J Edwards, PHD

  Liverpool John Moores University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Both researcher and participants did not know what of the two pill options were caffeine
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Reader Chronobiology and Environmental Physiology

Model Details: Double blinded counterbalanced design with three conditions

Study Record Dates

• First Submitted: February 25, 2026
• First Posted: March 12, 2026
• Study Start: December 8, 2025
• Primary Completion: March 25, 2026
• Study Completion: March 25, 2026
• Last Updated: March 13, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)