NCT06908941

Brief Summary

This study investigates the effects of 85% dark chocolate supplementation on vascular function and nitric oxide (NO) levels during high-intensity resistance exercise in healthy women across menstrual phases. Using a randomized crossover design, 31 women consumed either dark chocolate or milk chocolate before exercising during the early follicular and mid-luteal phases. Vascular markers, including pulse wave velocity (ftPWV), arterial stiffness, blood pressure, and plasma NO levels, were measured at multiple time points.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
31

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started Sep 2023

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

September 1, 2023

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2023

Completed
7 months until next milestone

Study Completion

Last participant's last visit for all outcomes

July 31, 2024

Completed
8 months until next milestone

First Submitted

Initial submission to the registry

March 19, 2025

Completed
15 days until next milestone

First Posted

Study publicly available on registry

April 3, 2025

Completed
Last Updated

April 4, 2025

Status Verified

April 1, 2025

Enrollment Period

4 months

First QC Date

March 19, 2025

Last Update Submit

April 2, 2025

Conditions

Vascular Function in Healthy Volunteers

Keywords

dark chocolateestrogencardiovascular function

Outcome Measures

Primary Outcomes (1)

  • Finger-Toe Pulse Wave Velocity (ftPWV)

    Measurements at other time points are taken while participants are resting in the laboratory. Firstly, sensors for photoplethysmography (PPG) were placed on the right index finger and right big toe of the participants. These sensors were marked with an oily pen to ensure consistent placement throughout the experiment. The signals were then amplified using a Biopec MP150 (MP150, Biopac Systems Inc., Goleta, CA, USA), with each physiological signal collected for at least 150 seconds. The signals were analyzed using MATLAB to calculate the time difference between the two pulse waves. The length of the participant's body segments ( sternum to the right index finger, and sternum to the big toe of the right foot) was measured, and this value was divided by the average difference between 10 pulse waves (in the stable interval of 150 seconds) to calculate the ftPWV value (m/s).

    Finger-toe pulse wave velocity (ftPWV) were measured at rest, 2 hours after chocolate consumption (baseline), immediately post-exercise (T0), and at 60 (T60) and 120 (T120) minutes post-exercise.

Secondary Outcomes (1)

  • Arterial Index

    Arterial index (API and AVI) were measured at rest, 2 hours after chocolate consumption (baseline), immediately post-exercise (T0), and at 60 (T60) and 120 (T120) minutes post-exercise.

Study Arms (2)

Early Follicular

EXPERIMENTAL

Participants consumed either 85% dark chocolate or milk chocolate (1g/kg body weight) before high-intensity resistance exercise during the early follicular (days 2-5) phases of two menstrual cycles.

Dietary Supplement: dark chocolateDietary Supplement: milk chocolateBehavioral: high-intensity resistance exercise

Mid-Luteal

ACTIVE COMPARATOR

Participants consumed either 85% dark chocolate or milk chocolate (1g/kg body weight) before high-intensity resistance exercise during the mid-luteal (days 18-24) phases of two menstrual cycles.

Dietary Supplement: dark chocolateDietary Supplement: milk chocolateBehavioral: high-intensity resistance exercise

Interventions

dark chocolateDIETARY_SUPPLEMENT

Participants consumed 85% dark chocolate (1g/kg body weight) before high-intensity resistance exercise during the early follicular (days 2-5) and mid-luteal (days 18-24) phases of two menstrual cycles. Finger-toe pulse wave velocity (ftPWV), arterial stiffness, blood pressure, and plasma NO levels were measured at rest, 2 hours after chocolate consumption (baseline), immediately post-exercise (T0), and at 60 (T60) and 120 (T120) minutes post-exercise.

Early FollicularMid-Luteal
milk chocolateDIETARY_SUPPLEMENT

Participants consumed milk chocolate (1g/kg body weight) before high-intensity resistance exercise during the early follicular (days 2-5) and mid-luteal (days 18-24) phases of two menstrual cycles. Finger-toe pulse wave velocity (ftPWV), arterial stiffness, blood pressure, and plasma NO levels were measured at rest, 2 hours after chocolate consumption (baseline), immediately post-exercise (T0), and at 60 (T60) and 120 (T120) minutes post-exercise.

Early FollicularMid-Luteal
high-intensity resistance exerciseBEHAVIORAL

Participants performed high-intensity resistance exercise during the early follicular (days 2-5) and mid-luteal (days 18-24) phases of two menstrual cycles.

Early FollicularMid-Luteal

Eligibility Criteria

Age20 Years - 30 Years
Sexfemale
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • the healthy adult women,
  • aged 20-30 years, from a local university campus,
  • had a regular menstrual cycles in the past three months.

You may not qualify if:

  • (1) irregular menstrual cycles (menstrual cycle length \< 21 or \> 35 days in the past three months),
  • (2) pregnancy or lactation in the past year,
  • (3) history of cardiovascular or uterine surgery in the past six months,
  • (4) use of contraceptives or other female hormone medications,
  • (5) smoking or alcohol consumption habits,
  • (6) hypertension (blood pressure \> 140/90 mmHg), chronic diseases, heart disease, or other cardiovascular conditions, (7) allergy to cocoa products, nuts, or fruits.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

National Chung Cheng University

Chiayi County, Taiwan, Taiwan

Location

Related Publications (2)

  • Gaynor-Metzinger SHA, Triplett NT, Meucci M, Fasczewski KS, Flinchum DH, Collier SR. Central arterial stiffness, wave reflection, and heart rate variability following 4-week high-intensity resistance training intervention in young active women. Eur J Appl Physiol. 2022 Oct;122(10):2283-2293. doi: 10.1007/s00421-022-05003-4. Epub 2022 Jul 19.

    PMID: 35852625BACKGROUND

  • Wang CW, Fang SH, Yu TA, Chen LY, Wang CK, Wang SC, He CS. The Cardiovascular Benefits of Dark Chocolate Supplementation before High-Intensity Resistance Exercise in the Early Follicular and Mid-Luteal Phases of the Menstrual Cycle. Sports Med Open. 2025 Apr 18;11(1):39. doi: 10.1186/s40798-025-00850-9.

    PMID: 40249472DERIVED

Related Links

Study Officials

  • Cheng-Shiun He Professor

    National Chung Cheng University

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Masking Details
Double-blind
Purpose
PREVENTION
Intervention Model
CROSSOVER
Model Details: EF-MC: early follicular-milk chocolate EF-DC: early follicular-dark chocolate ML-MC: Mid Luteal-milk chocolate ML-DC: Mid Luteal-dark chocolate
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

March 19, 2025

First Posted

April 3, 2025

Study Start

September 1, 2023

Primary Completion

December 31, 2023

Study Completion

July 31, 2024

Last Updated

April 4, 2025

Record last verified: 2025-04

Data Sharing

IPD Sharing
Will not share

Available IPD Datasets

Informed Consent Form (CCUREC111122101)Access

Locations

TW(1)