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

Liverpool John Moores University

Status and phase: Active, not recruiting; Phase 2; Phase 1

Conditions: Caffeine; No Pill; Placebo - Control

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

Study type: Interventional

Funder types: Other

Identifiers

NCT07469852

251121LJMUSPSREC77

Details and patient eligibility

About

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.

Enrollment: 15 estimated patients

Sex: All

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy adults
• 18-35 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

Exclusion criteria

• 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.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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15 participants in 3 patient groups

Group 1

Experimental group

Description:

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

Treatment:

Other: Placebo

Drug: Caffeine (300 mg)

Other: No Pill

Group 2

Experimental group

Description:

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

Treatment:

Other: Placebo

Drug: Caffeine (300 mg)

Other: No Pill

Group 3

Experimental group

Description:

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

Treatment:

Other: Placebo

Drug: Caffeine (300 mg)

Other: No Pill