The Repeatability of the Effect of Caffeine Supplementation on Submaximal Physiological Responses and Cycling Time Trial Performance

St. Mary's University, Twickenham

Status: Not yet enrolling

Conditions: Caffeine

Treatments: Dietary Supplement: Caffeine; Dietary Supplement: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT06935214

SMU_ETHICS_2024-25_992

Details and patient eligibility

About

Recently, Grgic (2018) discussed the concept of responders and non-responders to caffeine supplementation highlighting the importance of the repeatability of results. However, the number of studies that have investigated this idea by repeating the same time-trial performance test multiple times with the same caffeine dose is sparse (Astorino et al., 2012; Del Coso et al., 2019). Furthermore, studies have shown that differences in the CYP1A2 genotype may account for some of the variation in time-trial performance (Guest et al., 2018). Thus, the current study aims to identify whether the effects of moderate caffeine supplementation (5 mg/kg) on time-trial performance are repeatable to aid the identification of responders and non-responders. Additionally, the study aims to determine if the CYP1A2 genotype may explain any of the variability in time-trial performance in trained male cyclists.

Enrollment: 12 estimated patients

Sex: Male

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• To be considered for inclusion in the study, participants must be regular cyclists, between 18 and 35 years of age, capable of completing a 20 km cycling time trial at a minimum speed of 30 km/h (arbitrary inclusion criteria to ensure a sufficient standard of athlete).

Exclusion criteria

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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12 participants in 2 patient groups, including a placebo group

Caffeine

Experimental group

Description:

5 mg/kg dose of caffeine (in pill form) - Trial 1

Treatment:

Dietary Supplement: Caffeine

Dietary Supplement: Caffeine

Placebo

Placebo Comparator group

Description:

5 mg/kg dose of placebo (Maltodextrin in pill form) - Trial 2

Treatment:

Dietary Supplement: Placebo