Effects of Caffeine Ingestion on Morning Cognitive and 4-km Time Trial Performance in Males

NCT07469852 | Active Not Recruiting Phase 1

• 1 other identifier: 251121LJMUSPSREC77
• 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. 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. Lopes-Silva et al. (2019) 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 caffeine (CAFF), NoPill (NOPILL) or Placebo (PLAC) effects on cognitive and 4-km time-trial (TT) performance. As a diurnal variation in 4-km TT has been widely reported in a similar population. The aim of the present study is to investigate if ingesting caffeine on the day of the morning test, to improve performance.

Conditions

Caffeine; Placebo - Control; No Pill

Keywords

Caffine; morning cognitive performance; morning 4-km time-trial performance

Outcome Measures

Primary Outcomes (8)

• Morning 4-km time-trial finishing time

  4-km cycling time-trial (Watbike Pro, Nottingham UK) finishing time in minute and seconds. \~ 4-6 minutes.

  From enrolment to last experimental session (~4 weeks)

• 4-km cycling time-trial split times every 1 km.

  4-km cycling time-trial (Watbike Pro, Nottingham UK) split times (in minutes and seconds) every 1 km.

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

• Heart rate every 1-km

  Heart rate measured every 1-km during the 4-km time-trial, using a heart rate monitor.

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

• Rating of perceived exertion every 1-km

  Rating of perceived exertion every 1-km for the 4-km time-trail. Measured on a 6 (no exertion) to 20 (maximal exertion) scale. Takes \~1 s.

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

• Perceived pacing taken at 2 and 4 km

  Perceived pacing taken at 2 and 4 km of the 4-km time trial. The scale is a 10 cm visual analogue scale where -5 represents pacing to slow to complete the 2 km as fast as possible, zero = optimal pacing and +5 went to fast. Takes \~1 s to answer.

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

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

  To assess the effect of 300 mg caffeine (CAFF) vs placebo (PLAC) vs no-pill (NoPill) on morning Trail Making Test time to completion in seconds (TMT; parts A and B). In part A the circles are numbered 1-25, and the participant is instructed to draw lines to connect the numbers in ascending order. In part B, the circles include both numbers (1-13) and letters (A-L) and the participant is instructed to draw lines to connect the circles in ascending pattern but with the added task of alternating between numbers and letters (i.e., 1-A-2-B-3-C etc.). In both parts the participant is instructed to connect to the circles as fast as possible, without lifting the pencil from the paper. If an error is made, this is pointed out immediately and the participant is allowed to correct it. During the test, time to completion is measured, with a higher time indicative of the greater impairment.

  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)

• Rectal temperature @rest and after warm-up

  From enrolment to last experimental session (4 weeks)

• Blood lactate @ rest, pre TT and after

  From enrolment to last experimental session (4 weeks)

• Mean skin temperature (Tsk)

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

• The mean body temperature (Tmb)

  From familiarisation to the final 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 (300 mg); Other: Placebo; Other: No Pill

Group 2

EXPERIMENTAL

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

Drug: Caffeine (300 mg); Other: Placebo; Other: No Pill

Group 3

EXPERIMENTAL

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

Drug: Caffeine (300 mg); Other: Placebo; Other: No Pill

Interventions

Caffeine (300 mg) DRUG

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

Group 1; Group 2; Group 3

Placebo 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.

Sponsors & Collaborators

• Liverpool John Moores University: lead

Study Sites (1)

Tom Reilly Building (LJMU)

Liverpool, Merseyside, L3 3AF, United Kingdom

Location

Related Publications (4)

• 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

• 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

• 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

• 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

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: 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 repeated measures counterbalanced design with three conditions

Study Record Dates

• First Submitted: February 25, 2026
• First Posted: March 13, 2026
• Study Start: January 12, 2026
• 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)