Short-Term Broccoli Supplementation and Acute Oxidative Stress Recovery

Effects of Short-Term Broccoli Powder Supplementation on Acute Oxidative Stress and Recovery Following a Metabolically Demanding Exercise Session

The study aimed to evaluate the effects of short-term broccoli powder supplementation on metabolically demanding exercise performance, muscle power, and blood lactate recovery. It also investigated broccoli powder-derived sulforaphane bioavailability and its effects in attenuating exercise-induced oxidative stress. Seventeen healthy males (age 23.8 ± 4.9 years, height 182.3 ± 6.1 cm, weight 80.0 ± 12.8 kg), in a double-blind crossover design, three weeks apart, consumed ten standard doses of either broccoli powder or spinach powder as a placebo over a period of 2 weeks. They then performed a maximal progressive cycling task with concomitant analysis of expired gas composition. Plasma malondialdehyde (MDA) level was measured before and 60 min after the completion of the task, and blood lactate and muscle power (counter-movement vertical jump (CMJ) performance) were measured before and up to 60 min after exercise.

Study Overview

• Status: Completed
• Conditions: Healthy Adult Male
• Intervention / Treatment: Dietary supplement: Broccoli powder; Dietary supplement: Placebo (no broccoli-derived bioactives)

Detailed Description

Intense exercise increases oxygen consumption and mitochondrial respiration, leading to elevated production of reactive oxygen species (ROS). While moderate ROS levels play an essential role in cellular signaling and training adaptation, excessive accumulation may overwhelm antioxidant defenses and promote oxidative damage to lipids, proteins, and nucleic acids. The balance between ROS production and endogenous antioxidant systems is therefore critical during and after strenuous exercise. Traditional antioxidant supplementation has produced inconsistent findings, with some evidence suggesting that high doses of exogenous antioxidants may blunt adaptive signaling. Consequently, attention has shifted toward nutritional strategies that enhance endogenous cytoprotective pathways rather than directly scavenging free radicals.

Broccoli is rich in glucoraphanin, the precursor of sulforaphane (SFN), a bioactive isothiocyanate formed through myrosinase-mediated hydrolysis. SFN activates the Nrf2 signaling pathway, upregulating phase II detoxifying and antioxidant enzymes such as heme oxygenase-1 and NAD(P)H quinone oxidoreductase-1, thereby strengthening intrinsic antioxidant defense mechanisms. Although sulforaphane has demonstrated cytoprotective and anti-inflammatory properties, its effects on exercise-induced oxidative stress in healthy, recreationally active individuals remain insufficiently characterized. The present study examined whether short-term broccoli powder supplementation enriched with myrosinase influences sulforaphane bioavailability, oxidative stress, performance, and recovery following metabolically demanding exercise.

Seventeen healthy young men (23.8 ± 4.9 years) completed a randomized, double-blind, placebo-controlled crossover study with a three-week washout period. Ethical approval was obtained from the Lithuanian Sports University Ethics Committee, and all participants provided written informed consent. Participants maintained habitual diet and physical activity and reported intake of caffeine, alcohol, cruciferous vegetables, and supplements prior to testing.

The intervention consisted of 10 g broccoli powder (99.5% broccoli powder, 0.5% mustard seed powder providing myrosinase; ~320 μg glucoraphanin per dose) mixed with 300 mL beverage. The placebo consisted of spinach powder prepared identically. Ten doses were consumed over 14 days, with the final dose ingested three hours before exercise testing.

Sulforaphane bioavailability was assessed from 24-hour urine collection after the first dose using liquid chromatography-mass spectrometry. The exercise protocol involved an incremental cycling test to voluntary exhaustion starting at 40 W with a ramp increase of 20 W per minute. Respiratory gases and heart rate were continuously measured, and VO₂max was determined as the highest 20-second average achieved, verified by standard physiological criteria.

Countermovement jump height was assessed before exercise and 1, 30, and 60 minutes post-exercise. Capillary blood lactate was measured pre-exercise and during recovery (1-60 minutes). Venous blood samples were collected before and one hour after exercise to determine plasma malondialdehyde concentration as a marker of lipid peroxidation. Data were analyzed using repeated measures ANOVA with statistical significance set at p < 0.05.

• Study Type: Interventional
• Enrollment (Actual): 17
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Lithuania
  • Kaunas, Lithuania
    • Lithuanian Sports University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• males;
• age:18-37 years;
• no illnesses or injuries in the month preceding data collection and were engaged in organized physical activity no more than twice per week.

Exclusion Criteria:

• Non-compliance with the study protocol, illness, or injury during the study period.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: male healthy volunteers aged 18-37 years; Participants completed both conditions in a crossover design with washout. They consumed 10 g broccoli powder (~320 μg glucoraphanin) or matched spinach placebo for 14 days (10 doses), final dose 3 h pre-test.

Dietary supplement: Broccoli powder; The intervention consisted of a single 35-mL scoop of broccoli powder (BrocAffex; 99.5% broccoli powder and 0.5% mustard seed powder), corresponding to 10 g of supplement and delivering 320 μg of glucoraphanin per serving. The supplement was mixed with 300 mL of chocolate oat milk (13 participants) or 300 mL of orange juice (4 participants).; Dietary supplement: Placebo (no broccoli-derived bioactives); 1/2 x 35 ml scoop of dried spinach powder blended with 300 ml of chocolate oat milk (13 participants) or orange juice (4 participants).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Sulforaphane, mg/24hours	Urine was collected over a 24-hours period following ingestion of the first supplementation dose in both conditions, and sulforaphane was subsequently extracted and analyzed up to one week after study completion.
Plasma malondialdehyde concentration, nmol/mL	Blood sample was collected before incremental cycling and 1 hour post-test in both conditions and plasma malondialdehyde concentration was subsequently analyzed up to one week after study completion.
Peak power output, Watts	During each experimental condition (at peak exercise during incremental ramp cycling test)
Maximal oxygen uptake, mL/min/kg	During each experimental condition (at peak exercise during incremental ramp cycling test)

Secondary Outcome Measures

Outcome Measure	Time Frame
Peak heart rate, beats per minute	During each experimental condition (at peak exercise during incremental ramp cycling test)
Blood lactate concentration, mmol/L	Capillary blood lactate was measured before the metabolically demanding exercise task, and then 1 minute, 3 minutes, 5 minutes, 30 minutes and 60 minutes post-exercise in both conditions.
Jump height, cm	Countermovement jump (CMJ) height was measured before (baseline), and then 1 minute, 30 minutes, and 60 minutes after the metabolically demanding exercise task in both conditions.

Collaborators and Investigators

• Sponsor: Lithuanian Sports University
• Investigators: Principal Investigator: Sigitas Kamandulis, Dr., Lithuanian Sports University

Study record dates

Study Major Dates

• Study Start (Actual): November 30, 2024
• Primary Completion (Actual): January 1, 2025
• Study Completion (Actual): January 10, 2025

Study Registration Dates

• First Submitted: February 5, 2026
• First Submitted That Met QC Criteria: March 3, 2026
• First Posted (Actual): March 6, 2026

Study Record Updates

• Last Update Posted (Actual): March 6, 2026
• Last Update Submitted That Met QC Criteria: March 3, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Bioavailability; Sulforaphane; Lactate; VO₂max
• Other Study ID Numbers: BI-TRS (M)-2024-703

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No