Effects of New Zealand Blackcurrant on Athletic Performance and Physiological Stress in Simulated Volleyball Matches

NCT07753395 | Completed

• 1 other identifier: CMUH113-REC3-100
• Study Type: interventional
• Target: 16
• Locations: 1 country
• Sites: 1

Brief Summary

Sixteen young, healthy, and physically active male college students were randomly assigned to receive either a placebo or NZBC supplement (300 mg/day) for seven days. Short-term NZBC supplementation enhanced athletic performance and effectively reversed inflammation and muscle damage induced by volleyball.

Conditions

Athletic Performance

Keywords

Athletic Performance; Supplement; New Zealand Blackcurrant

Outcome Measures

Primary Outcomes (6)

• Grip strength test

  Handgrip strength of both hands was evaluated using a digital dynamometer (T.K.K. 5401 GRIP-D, Takei Scientific Instruments Co., Ltd., Niigata, Japan). During testing, participants maintained a standing position with the shoulder abducted at approximately 20°-30° without rotation, the forearm in a neutral position, and both the elbow and wrist in 0° extension. Participants were instructed to exert maximum effort gripping the handle for 5 seconds. Handgrip strength tests were conducted before and after the simulated volleyball matches, as well as during the rest interval between the first and second simulated matches. At each time point, two trials were performed for each hand with a 1-minute rest interval between trials, and the maximum value was recorded in kilograms (kg).

  28 days

• Counter Movement Jump, CMJ

  Vertical jump performance was analyzed using the My Jump 2 application. Participants started from an upright standing position with the body straight, then performed a rapid countermovement followed immediately by a maximal vertical jump. Each participant performed two trials with a 1-minute rest interval between trials, and the best trial was recorded for analysis.

  28 days

• Agility T-test

  Agility was evaluated using the T-test with the BlazePod light-based reaction training system (Play Coyotta Ltd., Tel Aviv, Israel), with time recorded in seconds (s). Course Layout: Point A served as the start line. Point B was placed 9.14 m directly in front of Point A. Points C and D were placed 4.57 m to the left and right of Point B, respectively. Reaction pods were placed at each point. Test Procedure: Timing began upon departure from Point A. Participants were required to touch each pod using their outside hand throughout the trial: Forward Sprint: Sprint forward from A to B and touch pod B. Left Shuffle: Side-shuffle left to C and touch pod C. Right Shuffle: Side-shuffle right past B to D and touch pod D. Return \& Backpedal: Side-shuffle left back to B, touch pod B, then backpedal past A and touch pod A to complete the trial and stop timing.

  28 days

• Standing spike

  A designated landing area measuring 1.5 m x 1.5m was set up at a distance of 5 m from the net. The participant stood on a volleyball platform approximately 80 cm high and 1.5 m from the net. The participant was required to toss the ball to an appropriate height (approximately 1 m) and spike it into the designated area. Ball velocity was analyzed and recorded using the Kinovea motion analysis software (Kinovea, open-source video analysis software). Three trials were performed for each test, with a 30-second rest interval between trials.

  28 days

• Clinical Biochemistry of muscle damage biomarkers and blood glucose

  Blood samples were collected at four different time points (one and a half hours before the start of the volleyball special (B), immediately after the simulated volleyball game (E), after the experiment (24 hours), and after the experiment (48 hours). Changes in blood glucose levels were estimated using blood from the fingertips via an Accu-Chek® Guide blood glucose glucometer (Roche, Mannheim, Germany). Muscle damage biomarkers, including creatine kinase (CK), lactate dehydrogenase (LDH), and uric acid (UA), were measured in the serum. The CK (EC2.7.3.2), LDH (EC 1.1.1.27), and UA (C97792) concentrations were estimated using commercial analytical reagents (Beckman Coulter). An automated clinical chemistry analyzer was used to measure CK and LDH levels on a Beckman Coulter AU5800 (Beckman Coulter Inc., CA, USA).

  28 days

• Clinical Biochemistry of the inflammatory response

  Blood samples were collected at four different time points (one and a half hours before the start of the volleyball special (B), immediately after the simulated volleyball game (E), after the experiment (24 hours), and after the experiment (48 hours). According to the manufacturer's instructions, the pro-inflammatory cytokine TNF-α was analyzed with a commercial ELISA kit (BioLegend, San Diego, CA). An enzyme immunoassay read The absorbance at 450 nm within 15 minutes (Tecan GENios, A-5082, Austria). Concentrations of C-reactive protein (CRP) were measured using a human ELISA kit (E-80CRP, Immunology Consultants Laboratory, Inc., Newberg, OR, USA). The sample absorbance was read at 450 nm within 30 min.

  28 days

Secondary Outcomes (3)

• Superoxide Dismutase (SOD) Activity

  28 days

• Rating of Perceived Exertion, RPE

  28 days

• Visual analogue scale, VAS

  At the end of the simulated volleyball match, and 12, 24, 36, and 48 hours after the match, please clearly indicate the corresponding facial expression and record it by number.

Study Arms (2)

New Zealand blackcurrant (NZBC)

EXPERIMENTAL

Participants receive 300 mg of New Zealand blackcurrant extract daily for 7 days during one of the crossover periods, separated by a 14-day washout period.

Dietary Supplement: New Zealand blackcurrant (NZBC)

Placebo

PLACEBO COMPARATOR

Participants receive 300 mg of matching placebo daily for 7 days during one of the crossover periods, separated by a 14-day washout period.

Dietary Supplement: Placebo

Interventions

Placebo DIETARY_SUPPLEMENT

containing edible yellow No. 4, edible yellow No. 5, sucrose, silica, talc, oxidized starch, gelatin, magnesium stearate, and palm wax.

Placebo

New Zealand blackcurrant (NZBC) DIETARY_SUPPLEMENT

New Zealand Blackcurrant 35% Anthocyanin Extract Powder, Capsule Shell (Hydroxypropyl Methylcellulose), Anti-caking Agent (Magnesium Stearate)

New Zealand blackcurrant (NZBC)

Eligibility Criteria

• Age: 18 Years - 30 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male subjects aged 18-30 who regularly practice volleyball and are willing to participate in the experiment.

You may not qualify if:

• Smoking and alcohol consumption.
• Patients with diabetes, heart disease, respiratory disease, coagulation disorders, hematomas, or other medical conditions.
• Feeling unwell for other reasons during the study period.
• Taking any health supplements or medications within the past two months. A medical history questionnaire was completed to exclude any medical conditions, such as recent muscle, bone, tendon, or ligament injuries, or those with a fear of blood draws.

Sponsors & Collaborators

• China Medical University Hospital: lead

Study Sites (1)

China Medical University

Taichung, 404332, Taiwan

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Sixteen young healthy physically active male college students. Participants were crossed over for NZBC or placebo supplements, which was completed in seven days. Between the crossover trials, participants had a two-week washout period to nullify the effects of the supplement

Study Record Dates

• First Submitted: August 4, 2026
• First Posted: August 7, 2026
• Study Start: April 25, 2025
• Primary Completion: September 18, 2025
• Study Completion: October 31, 2025
• Last Updated: September 25, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

TW (1)