Effects of Purple Tea on Muscle Hyperemia and Oxygenation, Serum Markers of Nitric Oxide Production and Muscle Damage, and Exercise Performance
Main Article Content
Keywords
blood flow, Dietary supplement, Nitrates
Abstract
Introduction: Purple tea exhibits a unique composition of chemical constituents that may exert favorable outcomes related to recovery from muscle damage, improvements in blood flow, perfusion, and recovery. The purpose of this study was to examine the impact of a brief oral dosing period of purple tea in exercising humans after stressful, damaging exercise.
Methods: Using a randomized, placebo-controlled, double-blind, crossover study design, 30 healthy men (33.5 ± 11.4 years, 178.4 ± 7.6 cm, 92.5 ± 13.3 kg) completed an eight day supplementation regimen consisting of either a maltodextrin placebo or 100 mg of purple tea extract (PurpleForceTM, Oryza Oil & Fat, Ltd.) interspersed with a two week washout period. After five and eight days of supplementation, changes in muscle oxygenation, body composition, reactive hyperemia, visual analog responses, exercise performance, and muscle damage markers were assessed. Data were analyzed using mixed factorial ANOVA, t-tests with 95% confidence intervals, and effect sizes (ES).
Results: Lactate dehydrogenase was significantly reduced (p = 0.04) in PT in comparison to PLA after eight days of supplementation and exercise performance challenge. In comparison to PT, arm circumference increased in PLA after five days of supplementation (p=0.04) and tended to be greater after eight days (p=0.06). Significantly greater decreases in impedance were observed in PT (p=0.02) while between-group differences in oxygen saturation post-leg extension exercise were greater in PT 30s into recovery (p=0.04) and tended to be greater 60s after recovery (p=0.06). Total bench press repetitions completed were greater in purple tea than PLA (p = 0.001). Total leg extension repetitions completed tended to be different between groups (p=0.09) while the total number of repetitions completed in purple tea increased from day five to day eight (p<0.001) with no change in PLA (p=0.37). No between-group changes were observed in the visual analog scales; however, only the PT condition experienced a significant improvement in Willingness to Exercise (p=0.02).
Conclusions: Acute supplementation of PT decreased lactate dehydrogenase, a marker of muscle damage, while also improving lower body muscle endurance performance.
References
2. Cherotich L, Kamunya S, Alakonya A, et al. Variation in catechin composition of popularly cultivated tea clones in East Africa (Kenya). Paper presented at: 2013 JKUAT Annual Scientific Conference Proceedings2013; Nairobi, Kenya.
3. Kilel EC, Faraj AK, Wanyoko JK, Wachira FN, Mwingirwa V. Green tea from purple leaf coloured tea clones in Kenya- their quality characteristics. Food Chem. 2013;141(2):769-775.
4. Shimoda H, Hitoe S, Nakamura S, Matsuda H. Purple Tea and Its Extract Suppress Diet- induced Fat Accumulation in Mice and Human Subjects by Inhibiting Fat Absorption and Enhancing Hepatic Carnitine Palmitoyltransferase Expression. Int J Biomed Sci. 2015;11(2):67- 75.
5. Jowko E, Sacharuk J, Balasinska B, et al. Effect of a single dose of green tea polyphenols on the blood markers of exercise-induced oxidative stress in soccer players. Int J Sport Nutr Exerc Metab. 2012;22(6):486-496.
6. Panza VS, Wazlawik E, Ricardo Schutz G, Comin L, Hecht KC, da Silva EL. Consumption of green tea favorably affects oxidative stress markers in weight-trained men. Nutrition. 2008;24(5):433-442.
7. Harty PS, Zabriskie HA, Erickson JL, Molling PE, Kerksick CM, Jagim AR. Multi-ingredient pre-workout supplements, safety implications, and performance outcomes: a brief review. J Int Soc Sports Nutr. 2018;15(1):41.
8. Herrlinger KA, Chirouzes DM, Ceddia MA. Supplementation with a polyphenolic blend improves post-exercise strength recovery and muscle soreness. Food Nutr Res. 2015;59:30034.
9. Jowko E, Dlugolecka B, Makaruk B, Cieslinski I. The effect of green tea extract supplementation on exercise-induced oxidative stress parameters in male sprinters. Eur J Nutr. 2015;54(5):783- 791.
10. Kerksick CM, Kreider RB, Willoughby DS. Intramuscular adaptations to eccentric exercise and antioxidant supplementation. Amino Acids. 2010;39(1):219-232.
11. Lee KA, Hicks G, Nino-Murcia G. Validity and reliability of a scale to assess fatigue. Psychiatry research. 1991;36(3):291-298.
12. Ziegenfuss TN, Habowski SM, Sandrock JE, Kedia AW, Kerksick CM, Lopez HL. A Two-Part Approach to Examine the Effects of Theacrine (TeaCrine(R)) Supplementation on Oxygen Consumption, Hemodynamic Responses, and Subjective Measures of Cognitive and Psychometric Parameters. Journal of dietary supplements. 2017;14(1):9-24.
13. Ziegenfuss TN, Kedia AW, Sandrock JE, Raub BJ, Kerksick CM, Lopez HL. Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR Trial. Nutrients. 2018;10(11).
14. Ziegenfuss TN, Lopez HL, Sandrock JE, Kedia AW, Habowski S, Kerksick C. Effect of a Multi- Nutrient Over-the-Counter Supplement on Changes in Metabolic Rate and Markers of Lipolysis. Journal of dietary supplements. 2017;14(3):288-302.
15. Lopez HL, Cesareo KR, Raub B, et al. Effects of Hemp Extract on Markers of Wellness, Stress Resilience, Recovery and Clinical Biomarkers of Safety in Overweight, But Otherwise Healthy Subjects. Journal of dietary supplements. 2020:1-26.
16. Malongane F, McGaw LJ, Mudau FN. The synergistic potential of various teas, herbs and therapeutic drugs in health improvement: a review. Journal of the science of food and agriculture. 2017;97(14):4679-4689.
17. Naveed M, BiBi J, Kamboh AA, et al. Pharmacological values and therapeutic properties of black tea (Camellia sinensis): A comprehensive overview. Biomed Pharmacother. 2018;100:521-531.
18. Hodgson AB, Randell RK, Jeukendrup AE. The effect of green tea extract on fat oxidation at rest and during exercise: evidence of efficacy and proposed mechanisms. Advances in nutrition.
2013;4(2):129-140.
19. Vazquez Cisneros LC, Lopez-Uriarte P, Lopez-Espinoza A, Navarro Meza M, Espinoza-
Gallardo AC, Guzman Aburto MB. Effects of green tea and its epigallocatechin (EGCG) content on body weight and fat mass in humans: a systematic review. Nutr Hosp. 2017;34(3):731- 737.
20. Turkozu D, Tek NA. A minireview of effects of green tea on energy expenditure. Crit Rev Food
Sci Nutr. 2017;57(2):254-258.