New Zealand Blackcurrant Symposium of CurraNZ research - ACSM Proceedings

Proceedings of the Blackcurrant Symposium, American College of Sports Medicine, Atlanta, May 28-30, 2025

 

Blackcurrant Polyphenol Benefits for Exercise Performance and Health

Speakers: Jeni Pearce, Professor Mark Willems, Dr Sam Shepherd 

 

Speaker 1: Jeni Pearce, NZRD, Performance Nutritionist, High Performance Sport New Zealand

Summary:
Pearce opened the symposium by welcoming delegates and providing an insightful introduction into the relevance of polyphenols and anthocyanins in health and nutrition science, with a focus on their increasing interest and application in sports performance and recovery. Her presentation set the foundation for the scientific presentations by contextualising the where, why, and how of anthocyanins - uniquely New Zealand blackcurrants - in health and sports performance nutrition.

Key Highlights:

1. What Are Polyphenols and Anthocyanins?

• Polyphenols are naturally occurring plant compounds found in common foods including fruit, vegetables, teas, herbs and spices with antioxidant, anti-inflammatory, vasodilatory, and immune-supporting properties. One of the benefits of increasing a plant-based diet is the rise in total polyphenol content.
• Anthocyanins are a sub-class of flavonoids, responsible for the red, blue, and purple pigments in fruits and vegetables.
• There are over 600 anthocyanins, and their levels vary greatly depending on the plant source, cultivar, and growing conditions.

2. Anthocyanin-Rich Foods in Sport

• Examples of commonly studied polyphenol-rich foods include beetroot (nitrate), cherries, blueberries, pomegranates, green tea, and blackcurrants.
• Pearce emphasized that blackcurrants, especially those grown in New Zealand, are gaining scientific attention due to their exceptionally high anthocyanin content and associated physiological effects that are being identified.

 

 

3. Why New Zealand Blackcurrants?

• Grown under high UV exposure, with cold winters and hot summers, New Zealand conditions create a stressful environment for the plants, leading to increased anthocyanin production by the plant as a form of protection.  Blackcurrants are also high in fibre and vitamin C.
• Compared to Northern Hemisphere varieties, NZ blackcurrants have up to 1.5-2x   the anthocyanin content, particularly delphinidins and cyanidins forms.
• Their phytochemical profile and the antioxidant potential of the NZ cultivars support the health and performance applications
• The benefits to health and performance are possibly linked to the presence of two specific anthocyanins (cyanidin and delphinidin).

4. Historical Context and Market Challenges

• In the US, prior to the late 1960s blackcurrants were banned due to concerns over a tree disease (fungus) threatening white pine trees and the timber industry limiting awareness and availability of the fruit.
• The fresh fruit has a short shelf life (6 weeks), making it unsustainable in the fresh form for consistent performance nutrition use.

5. Forms and Practical Use

• Available in a range of forms including frozen fruit, jams, juices, concentrates, powders, and capsule extracts.  Fresh forms have a very tart flavour.
• Capsules and standardized powders are most appropriate for controlled dosing,
• Flavoured products or food items (e.g., jams, juices) often do not provide sufficient anthocyanin levels for clinical or performance outcomes.
• Athletes were advised blackcurrant flavoured products, such as gels, will not contain the anthocyanin properties Processing focussing on retaining the high anthocyanin content in powders is a key consideration.

6. Dosing and Considerations

• Pearce stressed the importance of safer supplement use for athletes accountable under the WADA antidoping code; having products third-party batch tested and knowing the extract anthocyanin content of the product being used.
• For general health and recovery powders produced in food manufacturing sites may have different levels of key anthocyanins and are best used in health and recovery (added to breakfast cereals, smoothies, and baking).
• Serving sizes and product format (whole fruit vs. extract) influence bioavailability.

7. Applications in Elite Sport

• Use of the different forms depends on the outcome - new products are evolving.
• Blackcurrant powders and extract are used by elite athletes in New Zealand and internationally, often in capsule form (preferred due to a known defined dose and easy of travel).
• Products such as freeze-dried powders and extracts offer a practical solution with known anthocyanin levels.
• NZ Blackcurrants are identified in Group B the Australian Institute of Sport Supplement Framework that may benefit exercise performance recovery and health.
• Athletes are reminded to engage in appropriate fuelling and hydration strategies before, during and post competition and events, and to select products that are third party batch tested for safer supplement use.

Conclusion:

Jeni Pearce’s presentation served as an engaging and informative primer on the nutritional science of polyphenols ­– particularly anthocyanins from blackcurrants – and their evolving role in sports nutrition. Her practical expertise, paired with scientific context, established a compelling case for further exploration, standardization, and application of New Zealand blackcurrant anthocyanins in both health and athletic performance.

She handed over to researchers Prof. Mark Willems and Dr. Sam Shepherd to delve deeper into the mechanistic and physiological evidence supporting this emerging field.

References

1.     Physical parameters and chemical composition of fourteen blackcurrant cultivars (Ribes nigrum L.). Notulae Botanicae Horti Agrobotanici Cluj-Napoca 42.1 (2014): 160-167. 

2.     Comparison of polyphenols and anthocyanin content of different blackcurrant (Ribes nigrum L.) cultivars at the Polli Horticultural Research Centre in Estonia. (2020).

3.     High variability in flavonoid contents and composition between different North-European currant (Ribes spp.) varieties. Food Chemistry 204 (2016): 14-20.

 

Speaker 2: Professor Mark Willems – Exploring the Performance Effects of New Zealand Blackcurrant

In his presentation, Professor Mark Willems provided an in-depth overview of several studies exploring the ergogenic potential of New Zealand blackcurrant extract on various exercise models.

His findings contribute to a growing body of evidence supporting the use of blackcurrant anthocyanins for both endurance and intermittent high-intensity performance.

He also expanded on newer datasets involving repeatability of responses, substrate metabolism, and gastrointestinal protection in runners during exercise in heat.

Key Study 1: Time-Trial Performance Improvement

• Design: 16.1 km cycling time trial, 14 participants
• Intervention: 7-day supplementation of 105 mg of New Zealand blackcurrant anthocyanins (1 capsule/day)
• Results:
• 2.4% improvement in performance versus placebo
• This is comparable to the well-known 2.7% improvement from beetroot reported in previous research.
• Notably, up to 8.7% individual performance gains were observed.
• Methodological Rigor:
• Included two full familiarizations to minimize learning effects.
• Follow-up Consideration: Raised questions about whether performance gains were due to the chronic dosing or simply the final acute dose.

Cook, M. D., Myers, S. D., Blacker, S. D.et al (2015) New Zealand Blackcurrant Extract improves cycling performance and fat oxidation in cyclists. European Journal of Applied Physiology, 115 (11). pp. 2357-2365. ISSN 1439-631

Key Study 2: Community-Based Home Trial (COVID-Era Study)

• Design: Double-blind, placebo-controlled crossover with 34 recreational cyclists
• Dose: Single acute dose of 315 mg New Zealand blackcurrant anthocyanins (3 capsules)
• Key Insight:
• Slower cyclists (those with times >1400s) experienced noticeable improvements.
• Faster cyclists did not respond, suggesting dose or duration may need tailoring.
• Conclusion: The study highlighted the need to refine dosing strategies and account for interindividual responses, particularly for acute dosing.

Montanari, S., Blacker, S. D. and Willems, M. E. T. (2023) Acute Effects of New Zealand Blackcurrant Extract on Cycling Time-Trial Are Performance Dependent in Endurance-Trained Cyclists: A Home-Based Study. Sports (Basel, Switzerland), 11 (5). p. 93. ISSN 2075-4663

Key Study 3: High-Intensity Intermittent Exercise (Loughborough Intermittent Shuttle Test)

• Design: 7-day supplementation (105 mg of anthocyanins/day, i.e. 1 capsule/day), double-blind, placebo-controlled crossover
• Protocol: Multi-block (i.e. five) intermittent running involving walking, running at varied intensities, and repeated maximal sprints
• Focus: Analyzed the change in the fastest sprint from block 1 to assess fatigue and sprint maintenance
• Results:
• No effects in Blocks 2 and 3
• Significant preservation of sprint performance in Block 4 and 5
• Suggests blackcurrant helped mitigate fatigue, enabling athletes to maintain sprint speed later in the session
• Implication: Promising for team sports and other activities involving repeated high-intensity efforts

Mark ET Willems, Luke Cousins, David Williams and Sam D. Blacker. Beneficial Effects of New Zealand Blackcurrant Extract on Maximal Sprint Speed during the Loughborough Intermittent Shuttle Test. Sports, Published August 2016, 4(3), 42; doi:10.3390/sports4030042 doi:10.3390/sports4030042

Key study 4: High-Intensity Running Protocol – Initial Study

• Design: Intermittent running to exhaustion (19s run / 15s active recovery), 7-day dosing (105 mg of anthocyanins/day, i.e. 1 capsule/day)
• Finding:
• 11% increase in high-intensity running distance
• Placebo: ~2600m → Blackcurrant: +11% average
• Caveat: Not all individuals improved; the magnitude prompted further validation.

Perkins IC, Vine SA, Blacker SD, Willems ME, New Zealand Blackcurrant Extract Improves High-Intensity Intermittent Running.. Int J Sport Nutr Exerc Metab. 2015 26.http://dx.doi.org/10.1123/ijsnem.2015-0020

Key study 5: Repeatability Study – Confirming Consistency

• Design: Same test repeated twice per condition (placebo and blackcurrant), fully randomized, 210 mg of anthocyanins/day, i.e. 2 capsules/day for 7 days
• Participants: Recreational athletes involved in high-intensity intermittent sports
• Finding:
• 8 out of 16 participants were "repeat responders"
• These responders averaged a 16% performance improvement
• Suggests high inter-individual variability, warranting exploration of dose or duration effects

Perkins, I., Blacker, S. D. and Willems, M. E. T. (2024) Individual responses to repeated dosing with anthocyanin-rich New Zealand blackcurrant extract during high-intensity intermittent treadmill running in active males. Nutrients, 16 (24). pp. 1-11. ISSN 2072-6643

Key study 7: Substrate Utilization – Case Study in Ultra-Endurance Athlete

• Design: One individual tested pre- and post-7-day supplementation (210 mg of blackcurrant anthocyanins/day, i.e. 2 capsules/day), no placebo due to practical constraints
• Protocol: 2-hour treadmill run using Douglas bag technique, allowed standard energy gel intake
• Finding:
• +23% increase in fat oxidation
• −11% decrease in carbohydrate oxidation
• Insight: Even well-adapted endurance athletes may benefit from enhanced fat metabolism via anthocyanin metabolites

Willems, M. E. T. and Briggs, A. (2022) Running-induced metabolic and physiological responses using New Zealand Blackcurrant Extract in a male ultra-endurance runner. A case study. Journal of Functional Morphology and Kinesiology, 7 (104). pp. 1-9. ISSN 2411-5142

Key study 8: Exercise in the Heat – GI Protection

• Design: 1-hour run at moderate intensity in 34°C, male participants, placebo-controlled crossover (210 mg of anthocyanins/day, i.e 2 capsules/day for 7 days)
• Heat Storage: No difference in core temperature
• GI Damage (Key Focus):
• ↓40% in intestinal fatty acid binding protein (I-FABP) post-exercise
• I-FABP is a biomarker for intestinal epithelial damage
• GI Symptoms: Reduced from 11 participants (placebo) to 4 (blackcurrant), though 2 with severe symptoms reduced symptom score but remained severe
• Conclusion: Suggests protective effect on the gut, possibly tied to blackcurrant’s vascular and antioxidant properties

Lee, B. J., Flood, T. R., Hiles, A.et al (2022) Anthocyanin-rich blackcurrant extract preserves gastrointestinal barrier permeability and reduces enterocyte damage but has no effect on microbial translocation and inflammation after exertional heat stress. International Journal of Sport Nutrition and Exercise Metabolism, 32 (4). pp. 265-274. ISSN 1543-2742

Key Takeaways

• Performance Benefits: New Zealand blackcurrant shows potential benefits across endurance and intermittent high-intensity activities.
• Variability in Response: Highlights the need for individualized protocols – not all athletes respond similarly to the same dosing strategies.
• Next Steps: Further investigation needed to determine optimal dosing duration, intensity-specific applications, and gender-specific responses (especially under-represented female participants).

• Blackcurrant extract shows meaningful effects across diverse performance and physiological markers:
• High-intensity and endurance exercise enhancement
• Improved fat utilization, even in highly trained individuals
• Reduction in gut damage and GI symptoms during heat-stress exercise
• Individual variability is a consistent theme, reinforcing the importance of repeat testing and dosing optimization
• Ongoing and upcoming studies are expected to provide further confirmation of these promising early findings.
  
  

Professor Willems emphasized that while some results appeared “too good to be true,” the consistency across controlled studies supports the physiological potential of blackcurrant supplementation. The research underscores the extract’s emerging relevance as a natural performance-enhancing aid, with both aerobic and anaerobic applications. 

Speaker 3: Dr. Sam Shepherd: Exploring the Role of Blackcurrant Anthocyanins in Substrate Metabolism and Fat Oxidation

Dr. Sam Shepherd, formerly of Liverpool John Moores University and now with Precision Fuel & Hydration, shared insights from nearly a decade of research into how blackcurrant anthocyanins affect substrate metabolism and glucose homeostasis.

His interest was sparked in 2015 after receiving an enthusiastic email from Professor Mark Willems. Initially sceptical, Dr. Shepherd was intrigued by early findings showing enhanced fat oxidation during exercise following blackcurrant supplementation. This aligned with his own research, which focuses on using nutrition and exercise to influence metabolism and subsequently enhance both performance and health.

Key studies and findings highlighted:

• Initial Study (Mark Willems' lab):
• 7-day supplementation with 300 mg blackcurrant extract (~105 mg anthocyanins)
• Recreationally active participants exercised at varying intensities
• Result: Significant increase in fat oxidation at 65% VO₂ max

Cook, M. D., Myers, S. D., Blacker, S. D.et al (2015) New Zealand Blackcurrant Extract improves cycling performance and fat oxidation in cyclists. European Journal of Applied Physiology, 115 (11). pp. 2357-2365. ISSN 1439-6319

• Dose-Response Study:
• 300, 600, and 900 mg doses over 7 days
• 2-hour cycling at 65% VO₂ max
• Results: 20–24% increase in fat oxidation at 600–900 mg doses; small, non-significant effect at 300 mg
• Accompanied by a decrease in RER (respiratory exchange ratio), suggesting a shift toward greater fat usage

Cook, M. D., Myers, S. D., Gault, M. L.et al (2017) Dose effects of New Zealand Blackcurrant on substrate oxidation and physiological responses during prolonged cycling. European Journal of Applied Physiology, 117 (6). pp. 1207-1216. ISSN 1439-6319

• Female-Specific Study (Liverpool John Moores):
• 16 trained female cyclists, VO₂ max ~44 ml/kg/min
• 7-day supplementation of 600 mg blackcurrant extract vs placebo
• 2 hours of cycling at 65% VO₂ max
• Results: Modest but notable increase in fat oxidation and total fat utilization with blackcurrant
• Blood analysis showed slightly higher pre-exercise NEFA (non-esterified fatty acid) levels, suggesting possible enhanced lipolysis, though differences during exercise were not significant

 Dr. Shepherd concluded that blackcurrant anthocyanins appear to enhance fat oxidation during prolonged exercise, with dose-dependent effects, and may modestly improve pre-exercise fatty acid availability - at least in trained females. He emphasized the need for further mechanistic insights and broader applications, particularly for metabolic health and endurance performance.

Strauss, JA, Willems, MET and Shepherd, S New Zealand blackcurrant extract enhances fat oxidation during prolonged cycling in endurance-trained females. European Journal of Applied Physiology. ISSN https://doi.org/10.1007/s00421-018-3858-3 1439-6327

• Secondary analysis of trials measuring alterations to exercise-induced carbohydrate and fat oxidation, from Mark Willems’ lab
• Data from 116 participants (47 females and 69 males), ranging from recreationally active individuals to ultra-endurance athletes.
• Participants consumed the 35% anthocyanin extract in varying doses (105–420 mg of anthocyanins) and durations (single dose to two weeks) before engaging in different forms of exercise including walking, running, and cycling
• NZBC extract boosts fat oxidation in most individuals: The majority of participants showed an increase in fat oxidation and a corresponding decrease in carbohydrate oxidation during exercise after taking NZBC extract.
• Baseline metabolism matters: The stronger an individual’s natural tendency to burn carbs over fats (a higher RER), the more likely NZBC will shift metabolism toward fat burning. In contrast, individuals with an already low RER - meaning they naturally burn more fat - were more likely to show the opposite effect, with reduced fat oxidation and increased carbohydrate usage after supplementation.
• Consistent effects across sexes: Both men and women experienced similar metabolic shifts, with no significant sex-based differences in response to the supplement.

Willems, M. E. T. and Cook, M. D. (2025) Alterations of exercise-induced carbohydrate and fat oxidation by anthocyanin-rich New Zealand blackcurrant are associated with the pre-intervention metabolic function: a secondary analysis of randomized crossover trials, Nutrients, 17 (6). pp. 1-12. ISSN 2072-6643

Insulin Sensitivity Study

Dr. Shepherd presented data investigating the effect of blackcurrant extract on insulin sensitivity.

Study design:

• Overweight/obese individuals
• 8-day blackcurrant extract supplementation
• Oral Glucose Tolerance Test (OGTT) on Day 7, and Continuous Glucose Monitoring (CGM) on Day 8

Key findings:

• Reduced blood glucose and insulin responses during OGTT with blackcurrant vs placebo
• Improved insulin sensitivity, as shown by increased Matsuda index
• Real-world data using CGM confirmed better glucose control throughout the day:
• Reduced glucose area under the curve after breakfast and lunch
• No difference at dinner (likely due to high fat/protein composition)

A. Nolan, R. Brett, J. A. Strauss, C. E. Stewart, S. O. Shepherd Short‑term, but not acute, intake of New Zealand blackcurrant extract improves insulin sensitivity and free‑living postprandial glucose excursions in individuals with overweight or obesity. European Journal of Nutrition 2021 60:1253–1262

Final Takeaways

✅ Blackcurrant extract appears to:

• Influence fat oxidation and carbohydrate use during exercise, depending on an individual’s baseline metabolic rate and RER
• Improve glucose regulation both in the lab and free-living conditions — likely via increased insulin sensitivity

These findings help build a more complete picture of how New Zealand blackcurrant extract (like CurraNZ) may support metabolic flexibility, endurance performance, and post-exercise recovery.

*Please note, Dr Shepherd shared unpublished datasets in his session – these have not been included and are embargoed until their publication date. We will provide an update on these findings in shortly. 

Further research on New Zealand Blackcurrant (CurraNZ):

Performance and recovery in sport

 

1. Perkins IC, Blacker SD, Willems MET. Intra-individual Responses to New Zealand Blackcurrant Extract During High-Intensity, Intermittent Running: A Repeat Response Study. IJSNEM Vol. 29, Suppl 1, 2019  S1-11

2. Perkins, I.C., Bradley, M., Blacker, S.D., Willems, M.E.T. Effect Of New Zealand Blackcurrant Extract On Muscle Fibre-Specific Fatigue 23rd Annual Congress Of The European College Of Sport Science Dublin/Ireland, 4-7 July 2018 207

3. Potter, J.A., Hodgson, C.I., Broadhurst, M., Howell, L., Gilbert, J., Willems, M.E. and Perkins, I.C., 2019. Effects of New Zealand blackcurrant extract on sport climbing performance. European journal of applied physiology, pp.1-9.

4. Godwin C, Cook MD, Willems MET. Effect of New Zealand blackcurrant extract on performance during the running based anaerobic sprint test in trained youth and recreationally active male football players. Sports 5, 69, 2017. doi:10.3390/sports5030069. 

5. Perkins, I.C., Vine, S.A., Blacker, S.D., & Willems, M.E.T. (2015). New Zealand blackcurrant extract improves high-intensity intermittent running. International Journal of Sports Nutrition and Exercise Metabolism, 25(5), 487–493

6. Willems, M.E.T., Cousins, L., Williams, D., & Blacker, S.D. (2016). Beneficial effects of New Zealand blackcurrant extract on maximal sprint speed during the Loughborough Intermittent Shuttle Test. Sports, 4(3), 42.

7. Murphy C, Cook MD, Willems MET. Effect of New Zealand blackcurrant extract on repeated cycling time trial performance. Sports 5(2), 25, 2017. doi: 10.3390/sports5020025.

8. Lee BJ, Flood TR, Hiles AM,  Wheeler LEV, Costello R, Walker ER, Ashdown K, Willems MET, Kuennen MR.New Zealand Blackcurrant Extract Attenuates Enterocyte Damage Following Exertional Heat Stress IJSNEM Vol. 29,

9. Cook, M.D., Myers, S.D., Blacker, S.D. and Willems, M.E.T., 2015. New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists. European journal of applied physiology, 115(11), pp.2357-2365.

10. Willems, M.E.T., Şahin, M.A., Berendsen, T. and Cook, M.D., 2019. Effect of New Zealand Blackcurrant Extract on Cycling Performance and Substrate Oxidation in Normobaric Hypoxia in Trained Cyclists. Sports, 7(3), p.67.

11. Fryer S, Paterson C, Perkins IC, Gloster C, Willems ME, Potter JA. New Zealand Blackcurrant Extract Enhances Muscle Oxygenation During Forearm Exercise in Intermediate-Level Rock Climbers. International Journal of Sport Nutrition and Exercise Metabolism. 2020 May 26;1(aop):1-6.

12. Montanari S, Sahin M, Lee B, Blacker S, Willems MET. No Effects of New Zealand Blackcurrant Extract on Physiological and Performance Responses in Trained Male Cyclists Undertaking Repeated Testing across a Week Period. Sports 2020, 8, 114; doi:10.3390/sports8080114

13. Montanari S, Şahin MA, Lee B, Blacker S, Willems MET. No effects of different doses of New Zealand blackcurrant 1 extract on cardiovascular responses during rest and 2 submaximal exercise across a week in trained male cyclists. Int J Sport Nutr Exerc Metab 2020. DOI: 10.1123/ijsnem.2020-0164

14.  Fryer S, Giles D, Bird E, Stone K, Paterson C, Baláš J, Willems MET, Potter J, Perkins I.  New Zealand blackcurrant extract enhances muscle oxygenation during repeated intermittent forearm muscle contractions in advanced and elite rock climbers. 2020. European Journal of Sport Science, DOI: 10.1080/17461391.2020.182704

15. Hunt, J.E.A.; Coelho, M.O.C.; Buxton, S.; Butcher, R.; Foran, D.; Rowland, D.; Gurton, W.; Macrae, H.; Jones, L.; Gapper, K.S.;et al. Consumption of New Zealand Blackcurrant Extract Improves Recovery from Exercise-Induced Muscle Damage in Non-Resistance Trained Men and Women: A Double-Blind Randomised Trial. Nutrients 2021, 13, 2875. https:// doi.org/10.3390/nu1308287516.

16. Burnett, P.J.M.; Willems, M.E.T. Effects of New Zealand Blackcurrant Extract on Sequential Performance Testing in Male Rugby Union Players. Sports 2022, 10, 152. https://doi.org/10.3390/ sports10100152. *Data from personal communication with Professor Willems.

17. Willems et al Effect of New Zealand Blackcurrant Extract on Force Steadiness of the Quadriceps Femoris Muscle during Sustained Submaximal Isometric Contraction.  J. Funct. Morphol. Kinesiol. 2022, doi: 10.3390/jfmk7020044

18.  M Willems, S Montenari et al Acute Effects of NZBC on Cycling Time-Trial Are Performance Dependent in Endurance-Trained Cylists: A Home-Based Study, Sports 2023, 11, 93. https://doi.org/10.3390/sports11050093
19 Lee et al. Anthocyanin-rich blackcurrant extract preserves gastrointestinal barrier permeability and reduces enterocyte damage but has no effect on microbial translocation and inflammation after exertional heat stress, IJSNEM (in press) doi: 10.1123/ijsnem.2021-0330.
20. Willems, Lee et al Anthocyanin-rich New Zealand blackcurrant extract reduces running-induced gastro-intestinal symptoms in the heat, Research in Sports Medicine, https://doi.org/10.1080/15438627.2025.2471380
21. Moss, Brindley, Enright et al The effects of an acute dose of New Zealand blackcurrant extract on 5 km running performance, International Journal of Sport Nutrition and Exercise Metabolism, 2023, 33, 323-330, https://doi.org/10.1123/ijsnem.2023-0029
22. Lee et al,  New Zealand blackcurrant extract modulates the heat shock response in men during exercise in hot ambient conditions, Eu J Applied Physiology April 2024, https://doi.org/10.1007/s00421-024-05439-w
23 . Willems, Briggs et al,.Beneficial physiological and metabolic effects with acute intake of New Zealand blackcurrant extract during 4h of indoor cycling in a male Ironman athlete: A case study, J. Funct. Morphol. Kinesiol. 2024, 9(3), 141; https://doi.org/10.3390/jfmk9030141
24  I Perkins, S Blacker, M Willems et al, Individual responses to Repeated Dosing with anthocyanin-Rich New Zealand Blackcurrant Extract During High-Intensity, Intermittent Treadmill Running in Active Males, Nutrients, 2024, 16(24), 4253; https://doi.org/10.3390/nu16244253

 

EXERCISE METABOLISM

 

1. Şahin MA, Bilgiç  P, Montanari S, Willems MET. Effects of Daily and Intermittent Intake of New Zealand Blackcurrant Extract on Whole-Body Fat Oxidation During Moderate Intensity Exercise in Males  IJSNEM Vol. 29, Suppl 1, 2019 s1-4

2. Lee BJ, Flood TR , Hiles AM, Wheeler LEV, Costello R, Walker EF, Ashdown K, Kuennen MR, Willems MET. New Zealand Blackcurrant Extract Enhances Fat Oxidation During Submaximal Exercise in the Heat IJSNEM Vol. 29, Suppl 1, 2019 S1-8

3. Strauss JA, Willems MET, Shepherd SO. New Zealand blackcurrant extract enhances fat oxidation during prolonged cycling in endurance-trained females. European Journal of Applied Physiology 118(6), 1265-1272, 2018. doi: 10.1007/s00421-018-3858-3.

4. Cook MD, Myers SD, Blacker SD, Willems ME. New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists. European Journal of Applied Physiology. 2015 Nov 1;115(11):2357-65.

5. Cook MD, Myers SD, Gault ML, Edwards VC, Willems ME. Dose effects of New Zealand blackcurrant on substrate oxidation and physiological responses during prolonged cycling. European Journal of Applied Physiology. 2017 Jun 1;117(6):1207-16.

6. Cook MD, Edwards VC, Myers SD, Gault ML, Willems ME. Metabolic and Physiological Responses by New Zealand Blackcurrant during Cycling: A Dose-Response Study. Medicine & Science in Sports & Exercise. 48(5S):977-978, May 2016

7. Willems, M.E.T., Şahin, M.A., Berendsen, T. and Cook, M.D., 2019. Effect of New Zealand Blackcurrant Extract on Cycling Performance and Substrate Oxidation in Normobaric Hypoxia in Trained Cyclists. Sports, 7(3), p.67.

8. Willems, M., Parktin, N., Widjaja, W. and Ajjimaporn, A., 2018. Effect of new zealand blackcurrant extract on physiological responses at rest and during brisk walking in southeast asian men: A randomized, double-blind, placebo-controlled, crossover study. Nutrients, 10(11), p.1732.

9. Şahin M, Bilgiç P, Montanari S, Willems M. Intake Duration of Anthocyanin-Rich New Zealand Blackcurrant Extract Affects Metabolic Responses during Moderate Intensity Walking Exercise in Adult Males, Journal of Dietary Supplements. doi: 10.1080/19390211.2020.1783421

10. Willems M, Briggs A. Running-Induced Metabolic and Physiological Responses Using New Zealand Blackcurrant Extract in a Male ultra-Endurance Runner: A Case Study. Journal of Functional Morphology and Kinesiology, 2022 https://doi.org/10.3390/jfmk7040104

11. Willems, M.E.T.; Banic, M.; Cadden, R.; Barnett, L. Enhanced Walking-Induced Fat Oxidation by New Zealand Blackcurrant Extract Is Body Composition-Dependent in Recreationally Active Adult Females. Nutrients 2022, 14, 1475. https:// doi.org/10.3390/nu14071475
12. Fortis H, Jones RO, Herris MA, Barrett JS, Jones LO, Morton JP, Strauss JA, Shepherd SO New Zealand blackcurrant extract enhances skeletal muscle glycogen re-synthesis in response to Sub-Optimal Carbohydrate Ingestion. Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom ISENC conference 2022 
13. Jones LO, L Leung, H O Fortis, Barrett JS, Strauss JA, Shepherd SO New Zealand blackcurrant extract enhances whole-body fat oxidation but does not affect intramuscular triglyceride utilisation in human skeletal muscle. Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom ISENC conference 2022
14. Willems M.E.T Two weeks daily intake of anthocyanin-rich NZBCE enhances whole-body fat oxidation during supine rest in healthy males Dietary Supplements and Nutraceuticals 2023; 2(8): 30-40. DOI: 10.1080/19390211.2020.1783421.
15. Willems et al. Effects of CurraNZ, a New Zealand Blackcurrant Extract during Sables Athletes in Hot Conditions: Two Case Studies, J Func Morph Kinesiology https://doi.org/10.3390/jfmk9020076
16. Yusan Shan, Matthew  Cook, Effects of New Zealand blackcurrant extract on exercising  substrate utilisation and post exercise hypotension in males and females, International Journal of Sport Nutrition and Exercise Metabolism. Advance online publication. https://doi.org/10.1123/ijsnem.2024-0108.
17.  Alterations of Exercise-Induced Carbohydrate and Fat Oxidation by Anthocyanin-Rich New Zealand blackcurrant are associated with the Pre-Intervention Metabolic Function: A Secondary Analysis of Randomized Crossover Trials, M Willems, M Cook,  Nutrients, 2025, 17(6), 997, https://doi.org/10.3390/nu17060997

Cardiovascular function and GLYCEMIC  effects

 

1. Cook MD, Myers SD, Gault ML, Willems MET. Blackcurrant Alters Physiological Responses and Femoral Artery Diameter during Sustained Isometric Contraction. Nutrients. 2017, 9(6). pii: E556. doi: 10.3390/nu9060556.

2. Sahin M, Bilgic P, Montanari S, Willems M. Effects of Daily and Intermittent Intake of New Zealand Blackcurrant Extract on Cardiovascular Responses During Moderate Intensity Exercise in Males (P23-011-19).

3. Cook MD, Myers SD, Gault ML, Edwards VE, Willems MET. Cardiovascular Function during Supine Rest in Endurance Trained Males with New Zealand Blackcurrant: A Dose-Response Study. European Journal of Applied Physiology 117(2):247-254, 2017. doi: 10.1007/s00421-016-3512-x.

4. Willems MET, Parktin N, Widjaja W, Ajjimaporn A. Effect of New Zealand blackcurrant extract on physiological responses at rest and during brisk walking in Southeast Asian men: A randomized, double-blind, placebo-controlled, cross-over study. Nutrients 10(11). pii: E1732. doi: 10.3390/nu10111732.

5. Cook M, Amber S, Joyce J. Effect of New Zealand Blackcurrant on Blood Pressure, Cognitive Function and Functional Performance in Older Adults. Journal of Nutrition in Gerontology and Geriatrics, 2020 https://doi.org/10.1080/21551197.2019.1707740

6. Nolan A, Brett R, Strauss JA, Stewart CE, Shepherd SO. Short‑term, but not acute, intake of New Zealand blackcurrant extract improves insulin sensitivity and free‑living postprandial glucose excursions in individuals with overweight or obesity. A. Nolan1 · R. Brett1 · J. A. Strauss1 · C. E. Stewart1 · S. O. Shepherd1 European Journal of Nutrition (2020).

7. Okamoto T, Hashimoto Y, Kobayashi R, Nakazato K, Willems ME. Effects of blackcurrant extract on arterial functions in older adults: A randomized, double-blind, placebo-controlled, crossover trial. Clinical and Experimental Hypertension. 2020 May 14:1-8.

8. Cook, D; Dunne, A; Bosworth, M; Willems, MET. Effect of Intake Duration of Anthocyanin-Rich New Zealand Blackcurrant Extract on Cardiovascular Responses and Femoral Artery Diameter during Sustained Submaximal Isometric Contraction, Journal of Dietary Supplements 2021, DOI: 10.1080/19390211.2021.1948943

9. Yusan Shan, Matthew  Cook, Effects of New Zealand blackcurrant extract on exercising  substrate utilisation and post exercise hypotension in males and females, International Journal of Sport Nutrition and Exercise Metabolism. Advance online publication. https://doi.org/10.1123/ijsnem.2024-0108.