Skip Navigation LinksHome » Articles » PLANT-BASED DIETS AND ATHLETIC PERFORMANCE

PLANT-BASED DIETS AND ATHLETIC PERFORMANCE

– Written by Nanci S. Guest, Canada and Heidi Lynch, USA

 

 

INTRODUCTION

With the growing interest in the benefits of plant-based diets, it is relevant to consider whether plant-centered dietary approaches may influence athletic performance. Reasons for adopting plant-based diets include health benefits, religious or cultural practices, environmental and climate factors and ethical concerns for animals1,2. This review outlines which nutrients may differ between plant-based (PB) and omnivorous diets and how this may impact exercise performance. In addition, the use of nutritional supplements for general health or performance enhancement through selected ergogenic aids in those following PB diets will be covered briefly. 

Athletes’ dietary patterns range substantially in the degree of inclusion vs. the limiting or avoidance of animal-sourced foods (ASF). Although some advocate for the term “plant-based” to be used interchangeably with “vegan”3, which is a diet that is exclusively derived from plants, this review will use the term “plant-based” to mean a diet based on “all” or “mostly” plants. PB) diets are most widely understood as diets where ASF are consumed infrequently (e.g. <10-20% total energy intake), similar to vegetarian diet. In comparison, “vegan” or “veganism” is characterized as a justice movement and lifestyle that not only includes a strict PB diet, but also excludes the exploitation of animals in any form (e.g. clothing, entertainment). Accordingly, all vegans consume a PB diet but not all PB eaters are vegan. 

 

IMPACTS TO HEALTH AND PERFORMANCE 

PB diets are increasing in many western countries due to the growing recognition of their ability to lower the risk of many diseases1. Studies consistently report reductions in cardiovascular disease4, hypertension5, diabetes6, obesity7 and several cancers8-10 in those following PB diets. Analyses of the human microbiome after adoption of a PB diet have also revealed mechanistic insight into the benefits of plant-derived nutrition on microbiota diversity and populations11,12.  Prioritizing the health of the gut microbiome, through whole-foods PB diets, may also offer a targeted therapy for high-intensity training athletes to improve metabolic, immune, and gut barrier function13.

Potential mechanisms linking a diet high in PB foods to improved athletic performance are limited, but not absent14-16. Importantly, reports show that PB eating patterns neither improve nor hinder physical performance [17,18]. Indeed, in a review of eight studies no acute differences were found between a PB diet and an omnivorous diet in muscular power, muscular strength, anaerobic or aerobic performance17. Similarly, studies suggest that PB diets do not compromise endurance performance19 and may facilitate aerobic capacity in athletes20.

More recent findings also reported that a PB diet was not detrimental to endurance and muscle strength, and even showed superior submaximal endurance in vegans compared with omnivores16. It also appears that muscle and strength development with resistance training is supported by plant-sourced proteins to the same degree as ASF21-24, with even stronger support at ingestions rates of protein reaching ~1.6 g/kg/day24,25. In summary, based on the results of aforementioned studies, it appears that a PB diet can be a suitable option for athletes. 

The notion that a diet high in plant foods may offer performance benefits appears to have some merit and plausibility on several fronts15. Through higher fiber content and lower caloric density, PB diets have consistently been shown to reduce lower body fat26,27, which is a key performance goal in athletes to optimize body composition28. Due to the high carbohydrate content in PB diets, they foster effective maintenance of glycogen levels29. By reducing blood viscosity and improving vascular flexibility and endothelial function, PB diets may be expected to improve skeletal and cardiac tissue blood flow and oxygenation15. Vegetables, fruits, nuts, seeds, legumes and grains are packed with phytonutrients that have antioxidant and anti-inflammatory properties14,30. This can lead to reduced oxidative stress and inflammation, and thus, enhanced endurance performance, reduced muscle damage, boosted immunity and more efficient recovery from training and competition14

The comparability of PB diets to those higher in ASF with regard to performance along with the well-established health, environmental and ethical benefits of PB diets, make it an appealing choice for many athletes18. As with omnivorous diets, there are certain nutrients in PB diets that merit extra planning and attention to optimize health and performance for athletes. 

 

NUTRIENTS TO CONSIDER 

Protein

Historically, meat and other animal-derived proteins have been viewed as an integral component of athletes' diets, leading some to question the adequacy of PB diets for supporting muscle growth and exercise performance in athletes and active individuals. 

It is commonly thought that protein intake may be inadequate in PB diets. As we and others have argued22, the amounts and proportions of amino acids consumed by vegetarians and vegans are typically more than sufficient to meet and exceed individual daily requirements, provided a reasonable variety of foods are consumed and energy intake needs are being met22,31. The terms complete and incomplete are misleading in relation to plant protein. Ingesting protein from a variety of plant foods, over a 24-hour period, supplies enough of all indispensable (essential) amino acids when energy requirements are being met32.

The Recommended Dietary Allowance (RDA) is 0.8 grams of protein per kilogram of body weight; however, the Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine33 suggests that athletes should consume 1.2-2.0 grams of protein per kg to support the body’s adaptations to exercise and increased protein turnover due to training. As with the RDA, no unique recommendation is given for athletes following vegetarian or vegan diets. As long as athletes consume adequate energy (kcal) from a well-balanced diet, vegetarian and vegan athletes should be able to consume the recommended amounts of protein through their diet34

Several studies examining the dietary intakes of vegan and vegetarian endurance athletes have shown that these athletes  are meeting their recommended daily protein19,20. Food sources high in protein that are acceptable to sport-focused individuals following PB diets include soy products (tofu, tempeh, edamame, soymilk), pulses (beans, lentils, peas) and an array of plant-based meat substitutes and protein powders. Seeds, nuts, and whole grains, such as quinoa, and plant-based milks also contribute protein to the diet (see Table 1). 

 

Omega-3 Fats

Omega-3 fats may influence the preservation of strength and enhance recovery from heavy exercise through their anti-inflammatory effects35. The omega-3 fatty acid biosynthesis pathway converts α-linolenic acid (ALA) to eicosapentaenoic (EPA) acid and further into docosahexaenoic acid (DHA, integral to the visual process and synaptic functioning). ALA is found mainly in nuts, seeds and plant oils, and DHA and EPA are found in fish and other seafood36. While intakes of ALAs are generally higher in those following PB diets compared to omnivores, intakes of EPA and DHA are low in PB diets and virtually absent in vegans or strictly PB diets36. Despite the assumptions that PB eaters/vegans are at risk of deficiency due to low conversion of ALA to EPA and then to DHA37, there does not appear to be evidence of deficiencies in adults38. Moreover, some studies have shown vegans to have higher circulating DHA levels, with zero consumption, compared to fish-eaters39, likely due to higher than average intakes of ALA. This finding, along with new findings and hypotheses on ALA/EPA supplementation and conversion to DHA40,41, highlight the likelihood that PB eaters can maintain their serum DHA levels through consumption of ALAs only. There is no current RDA for EPA or DHA; therefore, those following a vegan or PB diet should focus on consuming adequate amounts of ALA (see Table 2) which may be higher than the RDA42 or obtain DHA directly through algal supplementation42.

 

Vitamin B12 

Vitamin B12 (cobalamin) is important for normal brain and nervous system functioning and helps to make DNA43. Vitamin B12 is also associated with red blood cell (RBC) formation and low levels may result in megaloblastic anemia44. Megaloblastic anemia limits the blood’s oxygen carrying capacity, thus reducing its availability to cells, which may negatively impact aerobic performance44. Individuals following PB diets must take particular care to consume enough vitamin B12, as it is mainly found in meat, eggs, and dairy products. Despite some reports in popular media, studies on naturally occurring and Vitamin B12-containing plant-derived food sources show that only nori (seaweed), is suitable as a Vitamin B12 source for vegetarians45,46. However, due to inconsistencies and variability in plant sources of B12 content, the only reliable and recommended PB/vegan sources of B12 are fortified breakfast cereals and nutritional yeasts, PB meat substitutes, PB milks and other fortified PB food products47. Those following a PB or vegan diet should take a B12 supplement and track intakes derived from  B12 fortified foods34,47.

 

Iron

The importance of iron to athletes is established through its biological role in supporting the function of proteins and enzymes essential for maintaining physical and cognitive performance48. Iron is incorporated into hemoglobin and myoglobin, proteins responsible for the transport and storage of oxygen49. Iron-deficiency anemia is the most common type of anemia among athletes, who have higher iron requirements due to increased erythropoietic drive through higher intensities and volumes of training50. The female athlete is at particular risk of iron deficiency due to menstruation and generally, a lower total energy or food intake compared to males51. Owing to a diet rich in whole-grains and legumes (good iron sources), both PB and vegans consume similar amounts of iron as omnivores27,52; however, the risk of iron deficiency is greater due to low bioavailability of iron from plant foods53. Accordingly, recommended iron intakes for individuals following PB or vegan diets are 1.8 times higher than for omnivores who consume ASF53: 32 mg/day (vs. 18 mg/day) for premenopausal adult women and 14 mg/day (vs.8 mg/day) for adult men and postmenopausal women. Table 3 displays iron content of selected plant-based foods. 

 

Zinc

Zinc serves as a catalyst for many enzymes in the body, is involved with cell differentiation and proliferation, and helps to regulate gene expression. It is also important for immunity54. Plant-based sources of zinc have lower bioavailability due to the presence of phytates (which are in legumes and whole grains) that bind zinc and inhibit its absorption55. Because of this reduced bioavailability, vegetarians may require 50% more zinc compared to omnivores48. This equates to male vegetarians needing 16.5 mg of zinc and female vegetarians needing 12 mg of zinc daily. Some preparation techniques that increase the bioavailability of plant sources of zinc include soaking and sprouting beans, nuts, seeds, and grains; leavening (bread has more bioavailable zinc compared to crackers); and using organic acids with zinc such as citric, malic, or lactic acid34,56. Some researchers suggest supplementation may be advisable for vegan athletes57, but this is not universally agreed upon. Soy, legumes, grains, seeds, nuts, beans, and fortified cereals are acceptable zinc sources for vegans and vegetarians. Table 4 provides a list of some zinc sources.

 

Vitamin D 

Vitamin D plays a critical role in regulating bone density by influencing calcium and phosphate absorption, and it also plays a role in immunity58. Currently the RDA for males and females ages 19-50 is 600 International Units (IU) per day59. Vitamin D is not found naturally in many foods. The International Olympic Committee consensus statement on dietary supplements and the high-performance athlete suggests that vitamin D supplements are commonly required for athletes (not just for vegetarians)60. Sufficient skin exposure to sunlight is an important source of this nutrient61. Factors affecting how much vitamin D is synthe-sized by the skin’s exposure to sunlight include skin pigmentation, and amount and intensity of sun exposure, which is affected by the time of day, season, and latitude62. About 10-15 minutes of skin exposure to the arms and should be sufficient to produce enough vitamin D62. Research has shown no significant differences between vegetarians and omnivores with respect to serum 25-hydroxyvitamin D status63. Food sources providing vitamin D include UV-irradiated mushrooms and fortified foods such as plant-based milks, orange juice, and cereals. It has been suggested that it may be beneficial for athletes to supplement 1,000-2,000 IUs/day, particularly if the athletes have minimal sun exposure61

 

Calcium

Like vitamin D, calcium is critically important for optimizing bone health. It helps maintain the integrity of the skeleton as part of hydroxyapatite. Additionally, calcium is involved with muscle contraction, vasoconstriction and dilation, hormonal responses, and the nervous system59. The RDA for males and females ages 19-50 is 1,000 mg per day59. Vegetarians who include dairy in their diets tend to consume similar amounts or more calcium compared to omnivores, although people who follow vegan diets tend to consume less calcium27,52,64. Plant sources of calcium may be less bioavailable due to the presence of oxalic acid59 and to a lesser extent, phytates and fiber34. The International Olympic Committee consensus statement on dietary supplements and the high-performance athlete notes that, as with vitamin D, calcium is a nutrient that often needs to be supplemented for athletes, regardless of their dietary pattern60. Table 5 presents calcium content and approximate absorption rate of select foods. 

 

Ergogenic Aids

Increased muscle creatine content can help athletes generate quick, explosive movements at high intensities, enhance performance in strength and power events, and help to increase muscle mass by supporting increased volumes of resistance exercise65. Dietary intake of creatine is low or absent in individuals following a PB or vegan diet66. It was assumed that PB eaters who exclude dietary creatine sources and have lower muscle creatine storage67 would experience greater ergogenic benefits. However, a recent systematic review66 found that creatine supplementation increased various parameters of performance in vegetarians and omnivores equally. Furthermore, the amount of creatine that is used in supplemental form to improve performance is 5 g per day as a maintenance dose, and 20 g per day for ~7 days as a loading dose, which cannot be practically achieved through dietary intakes alone. For example, an individual would have to consume 35 oz of beef, salmon or pork per day to reach the recommended daily maintenance dose of creatine for ergogenic goals of 5 g per day66.

Muscle carnosine also tends to be lower in vegetarians compared to omnivores68. Carnosine is found in skeletal muscle and the central nervous system, and is synthesised in situ from its rate-limiting precursor β-alanine69. There does not appear to be a significant relationship between dietary β-alanine consumption and muscle carnosine content68. Meat and poultry are the main sources of β-alanine in the diet, and β-alanine supplementation has been shown to increase muscle carnosine concentrations, benefiting high-intensity exercise performance by buffering excess hydrogen ions which can lead to premature fatigue70. Similar to creatine, the amount of β-alanine that is used in supplemental form to improve performance is 1.6 to 6.4 g per day for several days prior to an event, and an individual would have to consume up to 24 oz of poultry per day to reach the equivalent β-alanine dose required to enhance performance68.

In summary, well-designed PB diets that include some fortified foods, can provide adequate macro- and micro-nutrient intakes in athletes and active individuals to support health and performance. Abundant choices in the marketplace offer convenience and a variety of fortified food products and supplements for those choosing to follow a PB diet. Athletes should be taking extra care to plan out their sport nutrition strategies whether they choose to follow a strict or mostly PB diet, or an omnivore diet. 

 

Overview of the major food categories in a plant-based diet, with examples

·       Fruits: any type of fresh, frozen, or dried fruit including berries, apples, bananas, grapes, strawberries, citrus fruits, avocado etc. Dried fruits including figs, dates, raisins, apricots and others. 

·       Vegetables: plenty of veggies including peppers, broccoli, corn, asparagus, avocados, lettuce, spinach, kale, peas, collards, and others.

·       Tubers: root vegetables like potatoes, carrots, parsnips, sweet potatoes, beets, and others. 

·       Whole grains: grains, cereals, popcorn and other starches in their whole form, such as quinoa, brown rice, millet, whole wheat, oats, barley, and others.

·       Nuts, Seeds & Oils: walnuts, almonds, cashews, brazil nuts, peanuts, and pumpkin, hemp, flax and chia seeds. Olive, pumpkinseed, sunflower, soybean, canola, avocado and sesame oil and others. 

·       Legumes: beans of any kind, lentils, pulses, and soy.

 

 

Nanci S. Guest Ph.D., R.D., C.S.C.S.

Post-Doctoral Research Fellow 

Department of Nutritional Sciences

Faculty of Medicine, University of Toronto

Toronto, Canada

 

Heidi Lynch Ph.D., R.D.N.

Associate Professor

Point Loma Nazarene University

San Diego, USA

 

Contact: nanci.guest@mail.utoronto.ca

 

 

References

1.              Hemler, E.C. and F.B. Hu, Plant-Based Diets for Personal, Population, and Planetary Health. Adv Nutr, 2019. 10(Suppl_4): p. S275-S283.

2.              Panizza, S., If Veganism Is Not a Choice: The Moral Psychology of Possibilities in Animal Ethics. Animals (Basel), 2020. 10(1).

3.              Esselstyn, C.B., A plant-based diet and coronary artery disease: a mandate for effective therapy. J Geriatr Cardiol, 2017. 14(5): p. 317-320.

4.              Kahleova, H., S. Levin, and N.D. Barnard, Vegetarian Dietary Patterns and Cardiovascular Disease. Prog Cardiovasc Dis, 2018. 61(1): p. 54-61.

5.              Lee, K.W., et al., Effects of Vegetarian Diets on Blood Pressure Lowering: A Systematic Review with Meta-Analysis and Trial Sequential Analysis. Nutrients, 2020. 12(6).

6.              Kahleova, H., et al., A Plant-Based Dietary Intervention Improves Beta-Cell Function and Insulin Resistance in Overweight Adults: A 16-Week Randomized Clinical Trial. Nutrients, 2018. 10(2).

7.              Viguiliouk, E., et al., Effect of vegetarian dietary patterns on cardiometabolic risk factors in diabetes: A systematic review and meta-analysis of randomized controlled trials. Clin Nutr, 2019. 38(3): p. 1133-1145.

8.              Catsburg, C., et al., Dietary patterns and breast cancer risk: a study in 2 cohorts. Am J Clin Nutr, 2015. 101(4): p. 817-23.

9.              Tantamango-Bartley, Y., et al., Are strict vegetarians protected against prostate cancer? Am J Clin Nutr, 2016. 103(1): p. 153-60.

10.           Orlich, M.J., et al., Vegetarian dietary patterns and the risk of colorectal cancers. JAMA Intern Med, 2015. 175(5): p. 767-76.

11.           Hills, R.D., Jr., et al., Gut Microbiome: Profound Implications for Diet and Disease. Nutrients, 2019. 11(7).

12.           Valdes, A.M., et al., Role of the gut microbiota in nutrition and health. BMJ, 2018. 361: p. k2179.

13.           Crowson, M.M. and S.A. McClave, Does the Intestinal Microbiome Impact Athletic Performance? Curr Gastroenterol Rep, 2020. 22(11): p. 53.

14.           Trapp, D., W. Knez, and W. Sinclair, Could a vegetarian diet reduce exercise-induced oxidative stress? A review of the literature. J Sports Sci, 2010. 28(12): p. 1261-8.

15.           Barnard, N.D., et al., Plant-Based Diets for Cardiovascular Safety and Performance in Endurance Sports. Nutrients, 2019. 11(1).

16.           Boutros, G.H., et al., Is a vegan diet detrimental to endurance and muscle strength? Eur J Clin Nutr, 2020.

17.           Craddock, J.C., Y.C. Probst, and G.E. Peoples, Vegetarian and Omnivorous Nutrition - Comparing Physical Performance. Int J Sport Nutr Exerc Metab, 2016. 26(3): p. 212-20.

18.           Meyer, N. and A. Reguant-Closa, "Eat as If You Could Save the Planet and Win!" Sustainability Integration into Nutrition for Exercise and Sport. Nutrients, 2017. 9(4).

19.           Nebl, J., et al., Characterization, dietary habits and nutritional intake of omnivorous, lacto-ovo vegetarian and vegan runners–a pilot study. BMC nutrition, 2019. 5(1): p. 51.

20.           Lynch, H.M., C.M. Wharton, and C.S. Johnston, Cardiorespiratory fitness and peak torque differences between vegetarian and omnivore endurance athletes: A cross-sectional study. Nutrients, 2016. 8(11): p. 726.

21.           Messina, M., et al., No Difference Between the Effects of Supplementing With Soy Protein Versus Animal Protein on Gains in Muscle Mass and Strength in Response to Resistance Exercise. Int J Sport Nutr Exerc Metab, 2018. 28(6): p. 674-685.

22.           Lynch, H., C. Johnston, and C. Wharton, Plant-Based Diets: Considerations for Environmental Impact, Protein Quality, and Exercise Performance. Nutrients, 2018. 10(12).

23.           Lynch, H.M., et al., No Significant Differences in Muscle Growth and Strength Development When Consuming Soy and Whey Protein Supplements Matched for Leucine Following a 12 Week Resistance Training Program in Men and Women: A Randomized Trial. Int J Environ Res Public Health, 2020. 17(11).

24.           Morton, R.W., et al., A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med, 2018. 52(6): p. 376-384.

25.           Najjar, R.S. and R.G. Feresin, Plant-Based Diets in the Reduction of Body Fat: Physiological Effects and Biochemical Insights. Nutrients, 2019. 11(11).

26.           Rizzo, N.S., et al., Nutrient profiles of vegetarian and nonvegetarian dietary patterns. Journal of the Academy of Nutrition and Dietetics, 2013. 113(12): p. 1610-1619.

27.           Aragon, A.A., et al., International society of sports nutrition position stand: diets and body composition. J Int Soc Sports Nutr, 2017. 14: p. 16.

28.           Kanter, M., High-Quality Carbohydrates and Physical Performance: Expert Panel Report. Nutr Today, 2018. 53(1): p. 35-39.

29.           Upadhyay, S. and M. Dixit, Role of Polyphenols and Other Phytochemicals on Molecular Signaling. Oxid Med Cell Longev, 2015. 2015: p. 504253.

30.           Gardner, C.D., et al., Maximizing the intersection of human health and the health of the environment with regard to the amount and type of protein produced and consumed in the United States. Nutr Rev, 2019. 77(4): p. 197-215.

31.           Mariotti, F. and C.D. Gardner, Dietary Protein and Amino Acids in Vegetarian Diets-A Review. Nutrients, 2019. 11(11).

32.           Thomas, D.T., K.A. Erdman, and L.M. Burke, Position of the academy of nutrition and dietetics, dietitians of canada, and the american college of sports medicine: Nutrition and athletic performance. Journal of the Academy of Nutrition and Dietetics, 2016. 116(3): p. 501-528.

33.           Melina, V., W. Craig, and S. Levin, Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics, 2016. 116(12): p. 1970-1980.

34.           Heileson, J.L. and L.K. Funderburk, The effect of fish oil supplementation on the promotion and preservation of lean body mass, strength, and recovery from physiological stress in young, healthy adults: a systematic review. Nutr Rev, 2020.

35.           Sanders, T.A., DHA status of vegetarians. Prostaglandins Leukot Essent Fatty Acids, 2009. 81(2-3): p. 137-41.

36.           Saunders, A.V., B.C. Davis, and M.L. Garg, Omega-3 polyunsaturated fatty acids and vegetarian diets. Med J Aust, 2013. 199(S4): p. S22-6.

37.           Metherel, A.H. and R.P. Bazinet, Updates to the n-3 polyunsaturated fatty acid biosynthesis pathway: DHA synthesis rates, tetracosahexaenoic acid and (minimal) retroconversion. Prog Lipid Res, 2019. 76: p. 101008.

38.           Welch, A.A., et al., Dietary intake and status of n-3 polyunsaturated fatty acids in a population of fish-eating and non-fish-eating meat-eaters, vegetarians, and vegans and the product-precursor ratio [corrected] of alpha-linolenic acid to long-chain n-3 polyunsaturated fatty acids: results from the EPIC-Norfolk cohort. Am J Clin Nutr, 2010. 92(5): p. 1040-51.

39.           Metherel, A.H., et al., Compound-specific isotope analysis reveals no retroconversion of DHA to EPA but substantial conversion of EPA to DHA following supplementation: a randomized control trial. Am J Clin Nutr, 2019. 110(4): p. 823-831.

40.           Domenichiello, A.F., A.P. Kitson, and R.P. Bazinet, Is docosahexaenoic acid synthesis from alpha-linolenic acid sufficient to supply the adult brain? Prog Lipid Res, 2015. 59: p. 54-66.

41.           Burns-Whitmore, B., et al., Alpha-Linolenic and Linoleic Fatty Acids in the Vegan Diet: Do They Require Dietary Reference Intake/Adequate Intake Special Consideration? Nutrients, 2019. 11(10).

42.           Hooshmand, B., et al., Association of Vitamin B12, Folate, and Sulfur Amino Acids With Brain Magnetic Resonance Imaging Measures in Older Adults: A Longitudinal Population-Based Study. JAMA Psychiatry, 2016. 73(6): p. 606-13.

43.           Nagao, T. and M. Hirokawa, Diagnosis and treatment of macrocytic anemias in adults. J Gen Fam Med, 2017. 18(5): p. 200-204.

44.           Pawlak, R., S.E. Lester, and T. Babatunde, The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: a review of literature. Eur J Clin Nutr, 2014. 68(5): p. 541-8.

45.           Watanabe, F., et al., Vitamin B(1)(2)-containing plant food sources for vegetarians. Nutrients, 2014. 6(5): p. 1861-73.

46.           Medicine, I.I.o. Vitamin B12 Fact Sheet for Health Professionals. 2020; Available from: https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/#en5.

47.           Medicine, I.o., Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. 2001, Washington DC: National Academy Press.

48.           Clenin, G., et al., Iron deficiency in sports - definition, influence on performance and therapy. Swiss Med Wkly, 2015. 145: p. w14196.

49.           Sim, M., et al., Iron considerations for the athlete: a narrative review. Eur J Appl Physiol, 2019. 119(7): p. 1463-1478.

50.           DellaValle, D.M., Iron supplementation for female athletes: effects on iron status and performance outcomes. Curr Sports Med Rep, 2013. 12(4): p. 234-9.

51.           Clarys, P., et al., Comparison of nutritional quality of the vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diet. Nutrients, 2014. 6(3): p. 1318-1332.

52.           Pawlak, R., J. Berger, and I. Hines, Iron Status of Vegetarian Adults: A Review of Literature. Am J Lifestyle Med, 2018. 12(6): p. 486-498.

53.           King, J.C., Zinc: an essential but elusive nutrient. The American journal of clinical nutrition, 2011. 94(2): p. 679S-684S.

54.           Hunt, J.R., Bioavailability of iron, zinc, and other trace minerals from vegetarian diets. The American journal of clinical nutrition, 2003. 78(3): p. 633S-639S.

55.           Lönnerdal, B., Zinc and health: current status and future directions. J Nutr, 2000. 130: p. 1378-83.

56.           Fuhrman, J. and D.M. Ferreri, Fueling the vegetarian (vegan) athlete. Current Sports Medicine Reports, 2010. 9(4): p. 233-241.

57.           DeLuca, H.F., Overview of general physiologic features and functions of vitamin D. The American journal of clinical nutrition, 2004. 80(6): p. 1689S-1696S.

58.           Medicine, I.o., Dietary Reference Intakes for Calcium and Vitamin D 2011, Washington DC: National Academy of Sciences.

59.           Maughan, R.J., et al., IOC consensus statement: dietary supplements and the high-performance athlete. International journal of sport nutrition and exercise metabolism, 2018. 28(2): p. 104-125.

60.           Larson-Meyer, D.E., Vegetarian and Vegan Diets for Athletic Training and Performance. Sports Science Exchange, 2018. 29(188): p. 1-7.

61.           Holick, M.F., Vitamin D deficiency. New England Journal of Medicine, 2007. 357(3): p. 266-281.

62.           Chan, J., K. Jaceldo-Siegl, and G.E. Fraser, Serum 25-hydroxyvitamin D status of vegetarians, partial vegetarians, and nonvegetarians: the Adventist Health Study-2. The American journal of clinical nutrition, 2009. 89(5): p. 1686S-1692S.

63.           Davey, G.K., et al., EPIC–Oxford: lifestyle characteristics and nutrient intakes in a cohort of 33 883 meat-eaters and 31 546 non meat-eaters in the UK. Public health nutrition, 2003. 6(3): p. 259-268.

64.           Kreider, R.B., et al., International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr, 2017. 14: p. 18.

65.           Kaviani, M., K. Shaw, and P.D. Chilibeck, Benefits of Creatine Supplementation for Vegetarians Compared to Omnivorous Athletes: A Systematic Review. Int J Environ Res Public Health, 2020. 17(9).

66.           Lukaszuk, J.M., et al., Effect of creatine supplementation and a lacto-ovo-vegetarian diet on muscle creatine concentration. Int J Sport Nutr Exerc Metab, 2002. 12(3): p. 336-48.

67.           Everaert, I., et al., Vegetarianism, female gender and increasing age, but not CNDP1 genotype, are associated with reduced muscle carnosine levels in humans. Amino Acids, 2011. 40(4): p. 1221-9.

68.           Harris, R.C., et al., Determinants of muscle carnosine content. Amino Acids, 2012. 43(1): p. 5-12.

69.           Trexler, E.T., et al., International society of sports nutrition position stand: Beta-Alanine. J Int Soc Sports Nutr, 2015. 12: p. 30.

 

 

 

 

Header image by freepik.com (Cropped)

Switch Language: list thumbnails
Bookmark and Share

Category

Sports Science

Volume 10
Targeted Topic - Sports Nutrition
view all articles in this issue

Article Images

Copyright © Aspetar Sports Medicine Journal 2021