Trial of the effects of caffeine intake timing on endurance performance: based on genotype

Impact of the Timing of Caffeine Ingestion on Endurance Exercise Performance Based on the CYP1A2 Genotype - Caffeine intake timing on endurance performance trial

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000054033

Enrollment

Registered

2024-04-01

Start date

2025-04-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Endurance performance

Interventions

Subjects ingest capsules containing 6 mg of caffeine per 1 kilogram of body weight. Ninety minutes later, they take a placebo capsule. Cycling time trial begins 30 minutes after ingesting the second c

Eligibility

Sex/Gender

Male

Inclusion criteria

Inclusion criteria: Healthy male aged 18 to 30 years old

Exclusion criteria

Exclusion criteria: Smokers Medication users

Design outcomes

Primary

Measure	Time frame
The duration of 10 km cycling time trial 120 minutes after the administration of the first capsule in each experiment	—

Secondary

Measure	Time frame
Heart rate, blood pressure, expired gases (oxygen uptake, carbon dioxide output, ventilation, respiratory exchange ratio), cardiac output, stroke volume, rate of perceived exertion (RPE) 120 minutes after the administration of the first capsule in each experiment	—

Countries

Japan

Contacts

Public ContactJINXINGZE CHENG

Waseda University Graduate School of Sport Sciences

teisinnseitaku@akane.waseda.jp04-2947-6833

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026