Caffeine Abstinence in Habituated Users: Cardiovascular Responses to Exercise With Blood Flow Restriction.

Area of Science:

• Exercise Physiology
• Cardiovascular Research
• Sports Science

Background:

• Blood flow restriction (BFR) resistance exercise research often mandates caffeine abstinence.
• This is to prevent potential cardiovascular alterations that could influence the BFR stimulus.
• Habituated caffeine users may experience attenuated effects, questioning the necessity of abstinence.

Purpose of the Study:

• To compare cardiovascular responses during BFR resistance exercise in habituated users who consume caffeine versus those who abstain.
• To determine if caffeine consumption impacts key physiological variables during BFR exercise.

Main Methods:

• Thirty participants completed a within-subject design across three visits.
• Familiarization and a caffeine intake questionnaire were followed by two experimental sessions.
• Participants performed BFR bicep curls (30% 1RM, 40% AOP) after either consuming caffeine (CAFF) or abstaining (ABS).
• Cardiovascular measures (AOP, SBP, DBP, HR) and repetitions to failure were recorded.

Main Results:

• Pre-exercise systolic blood pressure (SBP) was slightly higher in the CAFF condition.
• Exercise-induced changes in arterial occlusion pressure (AOP), SBP, diastolic blood pressure (DBP), and heart rate (HR) were similar between CAFF and ABS conditions.
• Participants completed more repetitions in the CAFF condition compared to the ABS condition.

Conclusions:

• For habituated caffeine users, continuing regular caffeine consumption does not significantly alter cardiovascular responses during BFR resistance exercise.
• Caffeine abstinence is likely not required for habituated individuals undergoing BFR exercise protocols.
• Findings support maintaining caffeine habits without compromising safety or efficacy in BFR training.