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Caffeine, CYPA12 and Resistance Exercise

Not Applicable
Recruiting
Conditions
CYP1A2 Polymorphism
Caffeine and Resistance Exercise
Interventions
Dietary Supplement: Caffeine
Dietary Supplement: Placebo
Registration Number
NCT06610110
Lead Sponsor
Alberto Pérez-López
Brief Summary

Introduction: Several studies have evaluated and confirmed the ergogenic effect of acute caffeine intake on sports performance, specifically on strength and power performance. However, it remains to be elucidated how CYP1A2 polymorphism influences the acute effects of caffeine on this type of exercise.

Objectives: The present study aims to analyze the effects of acute caffeine intake on muscular strength, power, and endurance performance according to CYP1A2 polymorphism in men and women.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
60
Inclusion Criteria
  • Age between ≥ 18 and ≤ 35 years.
  • Body mass index (BMI) lower than 25 kg/m².
  • Physically active subjects (≥150 min/week of moderate exercise).
  • Healthy men and women without neurological, cardiometabolic, immunological, or physical conditions that prevent them from performing physical exercise.
  • Participants capable of performing the tests.
Exclusion Criteria
  • History of neuromuscular, cardiac, or diseases that could affect liver or muscle metabolism.
  • Use of drugs or other stimulants that interfere with caffeine intake and intestinal absorption during the tests and study.
  • Body mass index (BMI) ≥ 25 kg/m².
  • Having undergone prolonged periods of forced physical inactivity during the 6 months prior to the study.
  • Performing strenuous exercise within 48 hours prior to the tests.
  • Failing to replicate the same food intake on the two experimental days.
  • Consuming caffeine after 6 PM on the day prior to training or testing.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Genotype AA - Male - CaffeineCaffeine-
Genotype AC or CC - Male - CaffeineCaffeine-
Genotype AA - Male - PlaceboPlacebo-
Genotype AC or CC - Male - PlaceboPlacebo-
Genotype AA - Female - CaffeineCaffeine-
Genotype AC or CC - Female - CaffeineCaffeine-
Genotype AA - Female - PlaceboPlacebo-
Genotype AC or CC - Female - PlaceboPlacebo-
Primary Outcome Measures
NameTimeMethod
cyp1a2 polymorphismBefore the beginning of the trial

Using saliva sample and PCR

Mean velocity at different %1RMThrough study completion, an average of 2 weeks

Measuring bar mean velocity desplacement during bench press and back squat exercises.

Peak velocity at different %1RMThrough study completion, an average of 2 weeks

Measuring bar peak velocity and time to reach peak velocity of bar desplacement during bench press and back squat exercises.

Mean power output at different %1RMThrough study completion, an average of 2 weeks

Measuring during bench press and back squat exercises.

Peak power output and time to reach peak power output at different %1RMThrough study completion, an average of 2 weeks

Measuring during bench press and back squat exercises.

Number of repetitions performed in 1 set at 65%1RM until task failureThrough study completion, an average of 2 weeks

In bench press and back squat exercises

Bar velocity deplacement performed in 1 set at 65%1RM until task failureThrough study completion, an average of 2 weeks

In bench press and back squat exercises

Power output generated in 1 set at 65%1RM until task failureThrough study completion, an average of 2 weeks

In bench press and back squat exercise

Maximal Fat Oxidation Rate (MFO)Through study completion, an average of 2 weeks

g/min (MFO) using a metabolic chart.

Resting Metabolic Rate (RMR)Through study completion, an average of 2 weeks

Kcal at rest (RMR) using a metabolic chart.

Secondary Outcome Measures
NameTimeMethod
Mood state (tension, depression, anger, vigor, fatigue and confusion)Through study completion, an average of 2 weeks

Participants graded a set of 29 items related to the mood on a Likert scale from 0 (not at all) to 4 (extremely) in reply to the question: How do you feel at this moment? to assess six scales: tension, depression, anger, vigor, fatigue and confusion.

Adverse effectsThrough study completion, an average of 2 weeks

perception of power, endurance, energy and exertion, as well as heart, muscular and gastrointestinal discomfort

handgrip and isometric mid-thigh pull testsThrough study completion, an average of 2 weeks

N generated

Vertical Jump (cm)Through study completion, an average of 2 weeks
Vertical Jump (power)Through study completion, an average of 2 weeks

Trial Locations

Locations (1)

Facultad de Medicina y Ciencias de la Salud. Universidad de Alcalá

🇪🇸

Alcalá de Henares, Madrid, Spain

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