B-Vitamins (B6 and B12)

Overview: 

B-vitamins are water soluble vitamins that are excreted as urine and not created in the body so they need to be replenished through dietary intake. They all play different essential roles in catabolic and anabolic metabolism, and deficiencies can negatively affect metabolism of amino acids, glucose, and fatty acids. In terms of exercise, vitamins B6 (pyridoxine) and B12 (cobalamin) have significant literature on their effects in exercise. It is recommended that men get 1-1.7 mg/day of B6, and 2.4 mcg of B12. You can get this through diet by consuming meat, poultry, and fish, which are excellent sources, and excess intake is excreted through urine [2].

Simple: 

Vitamin B6 and B12 are important for enhancing exercise performance and recovery. Vitamin B6 helps break down carbohydrates, proteins, and fats, which provide essential energy during workouts. It also regulates homocysteine, a compound that can rise during exercise due to stress. Elevated homocysteine levels are linked to an increased risk of heart issues and stroke, making B6 crucial for maintaining healthy levels. Additionally, B6 supports recovery and strength, particularly as we age [1,2,3,4,5].

Vitamin B12, on the other hand, plays a key role in producing red blood cells, supporting nerve function, and aiding DNA synthesis. It is primarily found in animal products, with methylcobalamin being the preferred form for better absorption compared to synthetic versions. Together, B6 and B12, especially in higher doses, can help reduce muscle fatigue, improve recovery, and boost endurance, making them beneficial for anyone engaged in regular physical activity [1,2,3,4,5].

Complex:

Starting off with vitamin B6, pyridoxine or pyridoxal 5′-phosphate in its active form, this is a significant coenzyme which supports maintenance of homocysteine levels, increasing risk for dementia, heart attack, and stroke [2]. This is important because homocysteine increases from exercise or performance activities due to a high level of oxidative stress, which provides a need for adequate B6 and B12 to alleviate that elevated homocysteine [4]. This coenzyme also supports the breakdown of carbohydrates, proteins, and fats which are pertinent to a exercised individual. Vitamin B12, or cobalamin, is released from animal protein after reacting with gastric acid in the stomach, where it combines with an intrinsic factor leading to its absorption in the distal ileum. This vitamin is required for RBC (red blood cell) production, myelin synthesis, a cofactor in DNA and RNA synthesis, and hormone, protein, and lipid synthesis and metabolism. For this compound however it is important to know what you’re ingesting [2]. Cyanocobalamin (synthetic) has been shown to have less positive health outcomes than its counterpart, methylcobalamin that is all natural and retained much better. 

Another important aspect of these B vitamins are that exercise increases the need for some of these, especially vitamin B6 which can help with performance and recovery, and in the regulation of homocysteine which results from oxidative stress [5]. A study done on healthy older adults showed a decrease in time to do a chair raise in the vitamin B6 group compared to the placebo. In a similar way, the adults with the lowest level of physical activity had an association between higher intake of B6 to greater handgrip strength [1]. 

On a more significant note, one study using a mix of B-vitamins, taurine, and vitamin E displayed that the experimental group had decreased lactate production form 5-30 minutes after exercise, and an accelerated recovery. They also displayed a decreased NH3 (ammonia) levels which is a toxic byproduct. They also found in terms of endurance the supplemented group had improvements in time to exhaustion from baseline than the placebo. The amounts were as follows, “One vitamin B complex tablet (Ex PLUS®) contains vitamin B1 (33.6 mg), vitamin B2 (10 mg), vitamin B6 (50 mg), vitamin B12 (750 µg), vitamin E (16.8 mg), inositol (20 mg), calcium (18.9 mg), and taurine (20 mg).” [3]. When looking at this it is commonly known that the taurine at such a low dose will not be the cause of the results from this experiment, and little is known about the effect of B1, B2, and vitamin E on performance. The high doses of B6 and B12 however indicate that they may have been the ones to blame for the results presented more or less. They also were given at a high dose compared to recommendation, so a lower dose would theoretically be sufficient for exercise performance, something higher than the daily needed, but not necessarily as high as in the study, since these are water soluble vitamins that will be excreted as urine if in an excess.

Works Cited:

1. Grootswagers P, Mensink M, Berendsen AAM, Deen CPJ, Kema IP, Bakker SJL, Santoro A, Franceschi C, Meunier N, Malpuech-Brugère C, Bialecka-Debek A, Rolf K, Fairweather-Tait S, Jennings A, Feskens EJM, de Groot LCPGM. Vitamin B-6 intake is related to physical performance in European older adults: results of the New Dietary Strategies Addressing the Specific Needs of the Elderly Population for Healthy Aging in Europe (NU-AGE) study. Am J Clin Nutr. 2021 Apr 6;113(4):781-789. doi: 10.1093/ajcn/nqaa368. PMID: 33515034; PMCID: PMC8024000.
2. Hanna M, Jaqua E, Nguyen V, Clay J. B Vitamins: Functions and Uses in Medicine. Perm J. 2022 Jun 29;26(2):89-97. doi: 10.7812/TPP/21.204. Epub 2022 Jun 17. PMID: 35933667; PMCID: PMC9662251.
3. Lee MC, Hsu YJ, Shen SY, Ho CS, Huang CC. A functional evaluation of anti-fatigue and exercise performance improvement following vitamin B complex supplementation in healthy humans, a randomized double-blind trial. Int J Med Sci. 2023 Aug 15;20(10):1272-1281. doi: 10.7150/ijms.86738. PMID: 37786445; PMCID: PMC10542023.
4. Shinagawa, A., Yamazaki, T., Minematsu, A. et al. Changes in homocysteine and non-mercaptoalbumin levels after acute exercise: a crossover study. BMC Sports Sci Med Rehabil 15, 59 (2023). https://doi.org/10.1186/s13102-023-00656-w
5. Woolf, K., & Manore, M. M. (2006). B-Vitamins and Exercise: Does Exercise Alter Requirements?. International Journal of Sport Nutrition and Exercise Metabolism, 16(5), 453-484. Retrieved Sep 5, 2024, from https://doi.org/10.1123/ijsnem.16.5.453