By Biomarker

MCV

  1. J. A. Smith et al., “Greater Erythrocyte Deformability in World-Class Endurance Athletes.,” The American Journal of Physiology 276, no. 6 (June 1999): H2188-2193, https://doi.org/10.1152/ajpheart.1999.276.6.H2188.
  2. G. J. W. M. Rietjens et al., “Red Blood Cell Profile of Elite Olympic Distance Triathletes. A Three- Year Follow-Up.,” International Journal of Sports Medicine 23, no. 6 (August 2002): 391–96, https://doi.org/10.1055/s-2002-33736.
  3. Monika Ciekot-Soltysiak et al., “Training-Induced Annual Changes in Red Blood Cell Profile in Highly- Trained Endurance and Speed-Power Athletes.,” The Journal of Sports Medicine and Physical Fitness 58, no. 12 (December 2018): 1859–66, https://doi.org/10.23736/S0022-4707.17.07819-7.

RBC, Hemoglobin and Hematocrit

  1. P. I. Johansson et al., “A Retrospective Cohort Study of Blood Hemoglobin Levels in Blood Donors and Competitive Rowers.,” Scandinavian Journal of Medicine & Science in Sports19, no. 1 (February 2009): 92–95, https://doi.org/10.1111/j.1600-0838.2008.00771.x.
  2. David Montero et al., “Haematological Rather than Skeletal Muscle Adaptations Contribute to the Increase in Peak Oxygen Uptake Induced by Moderate Endurance Training.,” The Journal of Physiology 593, no. 20 (October 15, 2015): 4677–88, https://doi.org/10.1113/JP270250.
  3. Charles R. Pedlar et al., “Iron Balance and Iron Supplementation for the Female Athlete: A Practical Approach.,” European Journal of Sport Science 18, no. 2 (March 2018): 295–305, https://doi.org/10.1080/17461391.2017.1416178.
  4. German Clenin et al., “Iron Deficiency in Sports – Definition, Influence on Performance and Therapy.,” Swiss Medical Weekly 145 (2015): w14196, https://doi.org/10.4414/smw.2015.14196.
  5. Richard J. Burden et al., “Is Iron Treatment Beneficial in, Iron-Deficient but Non-Anaemic (IDNA) Endurance Athletes? A Systematic Review and Meta-Analysis.,” British Journal of Sports Medicine 49, no. 21 (November 2015): 1389–97, https://doi.org/10.1136/bjsports-2014-093624.
  6. Lisa M. Sinclair and Pamela Sue Hinton, “Prevalence of Iron Deficiency with and without Anemia in Recreationally Active Men and Women.,” Journal of the American Dietetic Association 105, no. 6 (June 2005): 975–78, https://doi.org/10.1016/j.jada.2005.03.005.
  7. G. J. W. M. Rietjens et al., “Red Blood Cell Profile of Elite Olympic Distance Triathletes. A Three- Year Follow-Up.,” International Journal of Sports Medicine 23, no. 6 (August 2002): 391–96, https://doi.org/10.1055/s-2002-33736.
  8. Heimo Mairbaurl, “Red Blood Cells in Sports: Effects of Exercise and Training on Oxygen Supply by Red Blood Cells.,” Frontiers in Physiology 4 (2013): 332, https://doi.org/10.3389/fphys.2013.00332.
  9. Giovanni Lombardi et al., “Reticulocytes in Sports Medicine: An Update.,” Advances in Clinical Chemistry 59 (2013): 125–53, https://doi.org/10.1016/b978-0-12-405211-6.00005-x.
  10. Giuseppe Banfi et al., “Seasonal Variations of Haematological Parameters in Athletes.,” European Journal of Applied Physiology 111, no. 1 (January 2011): 9–16, https://doi.org/10.1007/s00421-010-1641-1.
  11. Tiffany Astolfi et al., “The Influence of Training Load on Hematological Athlete Biological Passport Variables in Elite Cyclists.,” Frontiers in Sports and Active Living 3 (2021): 618285, https://doi.org/10.3389/fspor.2021.618285.
  12. Monika Ciekot-Soltysiak et al., “Training-Induced Annual Changes in Red Blood Cell Profile in Highly- Trained Endurance and Speed-Power Athletes.,” The Journal of Sports Medicine and Physical Fitness 58, no. 12 (December 2018): 1859–66, https://doi.org/10.23736/S0022-4707.17.07819-7.
  13. Giuseppe Lippi et al., “Variation of Red Blood Cell Distribution Width and Mean Platelet Volume after Moderate Endurance Exercise.,” Advances in Hematology 2014 (2014): 192173, https://doi.org/10.1155/2014/192173.
  14. Jaroslaw Krzywanski et al., “Vitamin B12 Status and Optimal Range for Hemoglobin Formation in Elite Athletes.,” Nutrients 12, no. 4 (April 9, 2020), https://doi.org/10.3390/nu12041038.
  15. Carrero JJ, Bárány P, Yilmaz MI, Qureshi AR, Sonmez A, Heimbürger O, Ozgurtas T, Yenicesu M, Lindholm B, Stenvinkel P. Testosterone deficiency is a cause of anaemia and reduced responsiveness to erythropoiesis-stimulating agents in men with chronic kidney disease. Nephrol Dial Transplant. 2012 Feb;27(2):709-15. doi: 10.1093/ndt/gfr288. Epub 2011 May 26. PMID: 21617198.
  16. Clénin, G., Cordes, M., Huber, A., Schumacher, Y. O., Noack, P., Scales, J., & Kriemler, S. (2015). Iron deficiency in sports – definition, influence on performance and therapy. Swiss medical weekly145, w14196. https://doi.org/10.4414/smw.2015.14196
  17. Alaunyte, I., Stojceska, V., & Plunkett, A. (2015). Iron and the female athlete: a review of dietary treatment methods for improving iron status and exercise performance. Journal of the International Society of Sports Nutrition12, 38. https://doi.org/10.1186/s12970-015-0099-2

Platelets

  1. M. S. El-Sayed et al., “Blood Hemostasis in Exercise and Training.,” Medicine and Science in Sports and Exercise 32, no. 5 (May 2000): 918–25, https://doi.org/10.1097/00005768-200005000-00007.
  2. Michael R. Baria et al., “High Intensity Interval Exercise Increases Platelet and Transforming Growth Factor-Beta Yield in Platelet-Rich Plasma.,” PM & R : The Journal of Injury, Function, and Rehabilitation 12, no. 12 (December 2020): 1244–50, https://doi.org/10.1002/pmrj.12368.
  3. Robert C. Oh et al., “Mildly Elevated Liver Transaminase Levels: Causes and Evaluation.,” American Family Physician 96, no. 11 (December 1, 2017): 709–15.
  4. Giuseppe Lippi et al., “Variation of Red Blood Cell Distribution Width and Mean Platelet Volume after Moderate Endurance Exercise.,” Advances in Hematology 2014 (2014): 192173, https://doi.org/10.1155/2014/192173.

WBC

  1. P. L. Horn et al., “Lower White Blood Cell Counts in Elite Athletes Training for Highly Aerobic Sports.,” European Journal of Applied Physiology 110, no. 5 (November 2010): 925–32, https://doi.org/10.1007/s00421-010-1573-9.
  2. Willis, E. A., Shearer, J. J., Matthews, C. E., & Hofmann, J. N. (2018). Association of physical activity and sedentary time with blood cell counts: National Health and Nutrition Survey 2003-2006. PloS one13(9), e0204277. https://doi.org/10.1371/journal.pone.0204277
  3. Ljungstrom, L. R., Jacobsson, G., & Andersson, R. (2013). Neutrophil-lymphocyte count ratio as a biomarker of severe sepsis in Escherichia coli infections in adults. Critical Care17(Suppl 2), P25. https://doi.org/10.1186/cc11963
  4. Tossige-Gomes, R., Ottone, V. O., Oliveira, P. N., Viana, D. J., Araújo, T. L., Gripp, F. J., & Rocha-Vieira, E. (2014). Leukocytosis, muscle damage and increased lymphocyte proliferative response after an adventure sprint race. Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas47(6), 492–498. https://doi.org/10.1590/1414-431×20143187

Reticulocytes

  1. Yorck Olaf Schumacher et al., “Reticulocytes in Athletes: Longitudinal Aspects and the Influence of Long- and Short-Term Exercise.,” Drug Testing and Analysis 2, no. 10 (October 2010): 469–74, https://doi.org/10.1002/dta.180.
  2. Giovanni Lombardi et al., “Reticulocytes in Sports Medicine: An Update.,” Advances in Clinical Chemistry 59 (2013): 125–53, https://doi.org/10.1016/b978-0-12-405211-6.00005-x.
  3. Giuseppe Banfi et al., “Seasonal Variations of Haematological Parameters in Athletes.,” European Journal of Applied Physiology 111, no. 1 (January 2011): 9–16, https://doi.org/10.1007/s00421-010-1641-1.

Iron

  1. Simon Reinke et al., “Absolute and Functional Iron Deficiency in Professional Athletes during Training and Recovery.,” International Journal of Cardiology 156, no. 2 (April 19, 2012): 186–91, https://doi.org/10.1016/j.ijcard.2010.10.139.
  2. Natasha M. Archer and Carlo Brugnara, “Diagnosis of Iron-Deficient States.,” Critical Reviews in Clinical Laboratory Sciences 52, no. 5 (2015): 256–72, https://doi.org/10.3109/10408363.2015.1038744.
  3. Marius Baranauskas et al., “Dietary Acid-Base Balance in High-Performance Athletes.,” International Journal of Environmental Research and Public Health 17, no. 15 (July 24, 2020), https://doi.org/10.3390/ijerph17155332.
  4. James P. McClung, Erin Gaffney-Stomberg, and Jane J. Lee, “Female Athletes: A Population at Risk of Vitamin and Mineral Deficiencies Affecting Health and Performance.,” Journal of Trace Elements in Medicine and Biology : Organ of the Society for Minerals and Trace Elements (GMS) 28, no. 4 (October 2014): 388–92, https://doi.org/10.1016/j.jtemb.2014.06.022.
  5. Ruth Blanco-Rojo et al., “Influence of Diet, Menstruation and Genetic Factors on Iron Status: A Cross-Sectional Study in Spanish Women of Childbearing Age.,” International Journal of Molecular Sciences 15, no. 3 (March 6, 2014): 4077–87, https://doi.org/10.3390/ijms15034077.
  6. Charles R. Pedlar et al., “Iron Balance and Iron Supplementation for the Female Athlete: A Practical Approach.,” European Journal of Sport Science 18, no. 2 (March 2018): 295–305, https://doi.org/10.1080/17461391.2017.1416178.
  7. Marc Sim et al., “Iron Considerations for the Athlete: A Narrative Review.,” European Journal of Applied Physiology 119, no. 7 (July 2019): 1463–78, https://doi.org/10.1007/s00421-019-04157-y.
  8. German Clenin et al., “Iron Deficiency in Sports – Definition, Influence on Performance and Therapy.,” Swiss Medical Weekly 145 (2015): w14196, https://doi.org/10.4414/smw.2015.14196.
  9. Karsten Koehler et al., “Iron Status in Elite Young Athletes: Gender-Dependent Influences of Diet and Exercise.,” European Journal of Applied Physiology 112, no. 2 (February 2012): 513–23, https://doi.org/10.1007/s00421-011-2002-4.
  10. Sant-Rayn Pasricha et al., “Iron Supplementation Benefits Physical Performance in Women of Reproductive Age: A Systematic Review and Meta-Analysis.,” The Journal of Nutrition144, no. 6 (June 2014): 906–14, https://doi.org/10.3945/jn.113.189589.
  11. Richard J. Burden et al., “Is Iron Treatment Beneficial in, Iron-Deficient but Non-Anaemic (IDNA) Endurance Athletes? A Systematic Review and Meta-Analysis.,” British Journal of Sports Medicine 49, no. 21 (November 2015): 1389–97, https://doi.org/10.1136/bjsports-2014-093624.
  12. Robert C. Oh et al., “Mildly Elevated Liver Transaminase Levels: Causes and Evaluation.,” American Family Physician 96, no. 11 (December 1, 2017): 709–15.
  13. Lisa M. Sinclair and Pamela Sue Hinton, “Prevalence of Iron Deficiency with and without Anemia in Recreationally Active Men and Women.,” Journal of the American Dietetic Association 105, no. 6 (June 2005): 975–78, https://doi.org/10.1016/j.jada.2005.03.005.
  14. Romain Meeusen et al., “Prevention, Diagnosis, and Treatment of the Overtraining Syndrome: Joint Consensus Statement of the European College of Sport Science and the American College of Sports Medicine.,” Medicine and Science in Sports and Exercise 45, no. 1 (January 2013): 186–205, https://doi.org/10.1249/MSS.0b013e318279a10a.
  15. Shane Michael Heffernan et al., “The Role of Mineral and Trace Element Supplementation in Exercise and Athletic Performance: A Systematic Review.,” Nutrients 11, no. 3 (March 24, 2019), https://doi.org/10.3390/nu11030696.
  16. Nielsen, P., Nachtigall, D. Iron Supplementation in Athletes. Sports Med 26, 207–216 (1998). https://doi.org/10.2165/00007256-199826040-00001
  17. Stoffel, N. U., Zeder, C., Brittenham, G. M., Moretti, D., & Zimmermann, M. B. (2020). Iron absorption from supplements is greater with alternate day than with consecutive day dosing in iron-deficient anemic women. Haematologica105(5), 1232–1239. https://doi.org/10.3324/haematol.2019.220830
  18. https://www.uptodate.com/contents/treatment-of-iron-deficiency-anemia-in-adults#H9253776
  19. Soppi E. T. (2018). Iron deficiency without anemia – a clinical challenge. Clinical case reports6(6), 1082–1086. https://doi.org/10.1002/ccr3.1529
  20. Clénin G. E. (2017). The treatment of iron deficiency without anaemia (in otherwise healthy persons). Swiss medical weekly147, w14434. https://doi.org/10.4414/smw.2017.14434

Sodium

  1. Beat Knechtle et al., “Exercise-Associated Hyponatremia in Endurance and Ultra-Endurance Performance-Aspects of Sex, Race Location, Ambient Temperature, Sports Discipline, and Length of Performance: A Narrative Review.,” Medicina (Kaunas, Lithuania) 55, no. 9 (August 26, 2019), https://doi.org/10.3390/medicina55090537.
  2. Tamara Hew-Butler et al., “Exercise-Associated Hyponatremia: 2017 Update.,” Frontiers in Medicine 4 (2017): 21, https://doi.org/10.3389/fmed.2017.00021.
  3. C. Z. Hong and I. N. Lien, “Metabolic Effects of Exhaustive Training of Athletes.,” Archives of Physical Medicine and Rehabilitation 65, no. 7 (July 1984): 362–65.
  4. T. Meyer and S. Meister, “Routine Blood Parameters in Elite Soccer Players.,” International Journal of Sports Medicine 32, no. 11 (November 2011): 875–81, https://doi.org/10.1055/s-0031-1280776.
  5. Shane Michael Heffernan et al., “The Role of Mineral and Trace Element Supplementation in Exercise and Athletic Performance: A Systematic Review.,” Nutrients 11, no. 3 (March 24, 2019), https://doi.org/10.3390/nu11030696.
  6. Turner, M. J., & Avolio, A. P. (2016). Does Replacing Sodium Excreted in Sweat Attenuate the Health Benefits of Physical Activity?. International journal of sport nutrition and exercise metabolism26(4), 377–389. https://doi.org/10.1123/ijsnem.2015-0233
  7. Del Coso, J., González-Millán, C., Salinero, J. J., Abián-Vicén, J., Areces, F., Lledó, M., Lara, B., Gallo-Salazar, C., & Ruiz-Vicente, D. (2016). Effects of oral salt supplementation on physical performance during a half-ironman: A randomized controlled trial. Scandinavian journal of medicine & science in sports26(2), 156–164. https://doi.org/10.1111/sms.12427
  8. Eichner, E. Randy Genetic and other Determinants of Sweat Sodium, Current Sports Medicine Reports: July 2008 – Volume 7 – Issue 4 – p S36-S40 doi: 10.1249/JSR.0b013e31817f3b35
  9. Speedy DB, Rogers IR, Noakes TD, et al. Diagnosis and prevention of hyponatremia at an ultradistance triathlon.Clin J Sport Med 2000;10:52–58.
  10. Sharwood, Karen & Collins, Malcolm & Goedecke, Julia & Wilson, Gary & Noakes, Timothy. (2002). Weight
  11. Changes, Sodium Levels, and Performance in the South African Ironman Triathlon. Clinical journal of sportmedicine : official journal of the Canadian Academy of Sport Medicine. 12. 391-9. 10.1097/00042752-200211000-00012.
  12. D B Speedy, T D Noakes, I R Rogers, J M Thompson, R G Campbell, J A Kuttner, D R Boswell, S Wright, M Hamlin.Hyponatremia in ultradistance triathletes. Med Sci Sports Exerc 1999 Jun;31(6):809-15.
  13. O’Toole ML, Douglas PS, Laird RH, et al. Fluid and electrolyte status in athletes receiving medical care at anultradistance triathlon. Clin J Sport Med 1995;5:116–122

Potassium

  1. Marius Baranauskas et al., “Dietary Acid-Base Balance in High-Performance Athletes.,” International Journal of Environmental Research and Public Health 17, no. 15 (July 24, 2020), https://doi.org/10.3390/ijerph17155332.
  2. C. Z. Hong and I. N. Lien, “Metabolic Effects of Exhaustive Training of Athletes.,” Archives of Physical Medicine and Rehabilitation 65, no. 7 (July 1984): 362–65.
  3. T. Meyer and S. Meister, “Routine Blood Parameters in Elite Soccer Players.,” International Journal of Sports Medicine 32, no. 11 (November 2011): 875–81, https://doi.org/10.1055/s-0031-1280776.
  4. R. G. Hutchinson, B. Barksdale, and R. L. Watson, “The Effects of Exercise on Serum Potassium Levels.,” Chest 101, no. 2 (February 1992): 398–400, https://doi.org/10.1378/chest.101.2.398.
  5. https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/

Magnesium

  1. Volpe S. L. (2015). Magnesium and the Athlete. Current sports medicine reports14(4), 279–283. https://doi.org/10.1249/JSR.0000000000000178
  2. Nielsen, F. H., & Lukaski, H. C. (2006). Update on the relationship between magnesium and exercise. Magnesium research19(3), 180–189.
  3. Córdova A, Mielgo-Ayuso J, Roche E, Caballero-García A, Fernandez-Lázaro D. Impact of Magnesium Supplementation in Muscle Damage of Professional Cyclists Competing in a Stage Race. Nutrients. 2019; 11(8):1927. https://doi.org/10.3390/nu11081927
  4. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/magnesium-supplements/faq-20466270
  5. Zhang, Y., Xun, P., Wang, R., Mao, L., & He, K. (2017). Can Magnesium Enhance Exercise Performance?. Nutrients9(9), 946. https://doi.org/10.3390/nu9090946
  6. Cinar, V., Nizamlioğlu, M., & Moğulkoc, R. (2006). The effect of magnesium supplementation on lactate levels of sportsmen and sedanter. Acta physiologica Hungarica93(2-3), 137–144. https://doi.org/10.1556/APhysiol.93.2006.2-3.4
  7. Pollock, N., Chakraverty, R., Taylor, I., & Killer, S. C. (2020). An 8-year Analysis of Magnesium Status in Elite International Track & Field Athletes. Journal of the American College of Nutrition39(5), 443–449. https://doi.org/10.1080/07315724.2019.1691953

Folate

  1. Woolf K, Manore MM. B-vitamins and exercise: does exercise alter requirements? Int J Sport Nutr Exerc Metab. 2006 Oct;16(5):453-84. doi: 10.1123/ijsnem.16.5.453. PMID: 17240780.
  2. Woolf, K., Hahn, N. L., Christensen, M. M., Carlson-Phillips, A., & Hansen, C. M. (2017). Nutrition Assessment of B-Vitamins in Highly Active and Sedentary Women. Nutrients9(4), 329. https://doi.org/10.3390/nu9040329
  3. Kim YN, Hwang JH, Cho YO. The effects of exercise training and acute exercise duration on plasma folate and vitamin B12. Nutr Res Pract. 2016 Apr;10(2):161-6. doi: 10.4162/nrp.2016.10.2.161. Epub 2016 Feb 26. PMID: 27087899; PMCID: PMC4819126.
  4. Molina-López, J., Molina, J.M., Chirosa, L.J. et al. Effect of folic acid supplementation on homocysteine concentration and association with training in handball players. J Int Soc Sports Nutr 10, 10 (2013). https://doi.org/10.1186/1550-2783-10-10
  5. Habte, K., Adish, A., Zerfu, D., Kebede, A., Moges, T., Tesfaye, B., Challa, F., & Baye, K. (2015). Iron, folate and vitamin B12 status of Ethiopian professional runners. Nutrition & metabolism12, 62. https://doi.org/10.1186/s12986-015-0056-8
  6. Dinç, N., Yücel, S. B., Taneli, F., & Sayın, M. V. (2016). The effect of the MTHFR C677T mutation on athletic performance and the homocysteine level of soccer players and sedentary individuals. Journal of human kinetics51, 61–69. https://doi.org/10.1515/hukin-2015-0171
  7. Vidmar Golja, M., Šmid, A., Karas Kuželički, N., Trontelj, J., Geršak, K., & Mlinarič-Raščan, I. (2020). Folate Insufficiency Due to MTHFR Deficiency Is Bypassed by 5-Methyltetrahydrofolate. Journal of clinical medicine9(9), 2836. https://doi.org/10.3390/jcm9092836

Vitamin B12

  1. Krzywański, J., Mikulski, T., Pokrywka, A., Młyńczak, M., Krysztofiak, H., Frączek, B., & Ziemba, A. (2020). Vitamin B12 Status and Optimal Range for Hemoglobin Formation in Elite Athletes. Nutrients12(4), 1038. https://doi.org/10.3390/nu12041038
  2. Herrmann M, Obeid R, Scharhag J, Kindermann W, Herrmann W. Altered vitamin B12 status in recreational endurance athletes. Int J Sport Nutr Exerc Metab. 2005 Aug;15(4):433-41. doi: 10.1123/ijsnem.15.4.433. PMID: 16286674.
  3. https://ods.od.nih.gov/factsheets/vitamin%20B12-HealthProfessional/
  4. E. Andrès, K. Serraj, J. Zhu, A.J.M. Vermorken, The pathophysiology of elevated vitamin B12 in clinical practice, QJM: An International Journal of Medicine, Volume 106, Issue 6, June 2013, Pages 505–515, https://doi.org/10.1093/qjmed/hct051
  5. Hazra, A., Kraft, P., Selhub, J., Giovannucci, E. L., Thomas, G., Hoover, R. N., Chanock, S. J., & Hunter, D. J. (2008). Common variants of FUT2 are associated with plasma vitamin B12 levels. Nature genetics40(10), 1160–1162. https://doi.org/10.1038/ng.210

Vitamin D

  1. de la Puente Yagüe, M., Collado Yurrita, L., Ciudad Cabañas, M. J., & Cuadrado Cenzual, M. A. (2020). Role of Vitamin D in Athletes and Their Performance: Current Concepts and New Trends. Nutrients12(2), 579. https://doi.org/10.3390/nu12020579
  2. Dahlquist DT, Dieter BP, Koehle MS. Plausible ergogenic effects of vitamin D on athletic performance and recovery. J Int Soc Sports Nutr. 2015 Aug 19;12:33. doi: 10.1186/s12970-015-0093-8. PMID: 26288575; PMCID: PMC4539891.
  3. Jastrzębski, Z. (2015). EFFECT OF VITAMIN D SUPPLEMENTATION ON THE LEVEL OF PHYSICAL FITNESS AND BLOOD PARAMETERS OF ROWERS DURING THE 8-WEEK HIGH INTENSITY TRAINING.
  4. Diamond, T., Wong, Y. K., & Golombick, T. (2013). Effect of oral cholecalciferol 2,000 versus 5,000 IU on serum vitamin D, PTH, bone and muscle strength in patients with vitamin D deficiency. Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA24(3), 1101–1105. https://doi.org/10.1007/s00198-012-1944-7
  5. Carswell, A. T., Oliver, S. J., Wentz, L. M., Kashi, D. S., Roberts, R., Tang, J., Izard, R. M., Jackson, S., Allan, D., Rhodes, L. E., Fraser, W. D., Greeves, J. P., & Walsh, N. P. (2018). Influence of Vitamin D Supplementation by Sunlight or Oral D3 on Exercise Performance. Medicine and science in sports and exercise50(12), 2555–2564. https://doi.org/10.1249/MSS.0000000000001721
  6. Rebolledo BJ, Bernard JA, Werner BC, Finlay AK, Nwachukwu BU, Dare DM, Warren RF, Rodeo SA. The Association of Vitamin D Status in Lower Extremity Muscle Strains and Core Muscle Injuries at the National Football League Combine. Arthroscopy. 2018 Apr;34(4):1280-1285. doi: 10.1016/j.arthro.2017.10.005. Epub 2017 Dec 21. PMID: 29275983.
  7. Blue, M. N., Trexler, E. T., Hirsch, K. R., & Smith-Ryan, A. E. (2019). A profile of body composition, omega-3 and vitamin D in National Football League players. The Journal of sports medicine and physical fitness59(1), 87–93. https://doi.org/10.23736/S0022-4707.18.08122-7
  8. Bertisch, S. M., Sillau, S., de Boer, I. H., Szklo, M., & Redline, S. (2015). 25-Hydroxyvitamin D Concentration and Sleep Duration and Continuity: Multi-Ethnic Study of Atherosclerosis. Sleep38(8), 1305–1311. https://doi.org/10.5665/sleep.4914
  9. Backx, E. M., Tieland, M., Maase, K., Kies, A. K., Mensink, M., van Loon, L. J., & de Groot, L. C. (2016). The impact of 1-year vitamin D supplementation on vitamin D status in athletes: a dose-response study. European journal of clinical nutrition70(9), 1009–1014. https://doi.org/10.1038/ejcn.2016.133
  10. Goncalves, A., Roi, S., Nowicki, M., Dhaussy, A., Huertas, A., Amiot, M. J., & Reboul, E. (2015). Fat-soluble vitamin intestinal absorption: absorption sites in the intestine and interactions for absorption. Food chemistry172, 155–160. https://doi.org/10.1016/j.foodchem.2014.09.021
  11. van Ballegooijen, A. J., Pilz, S., Tomaschitz, A., Grübler, M. R., & Verheyen, N. (2017). The Synergistic Interplay between Vitamins D and K for Bone and Cardiovascular Health: A Narrative Review. International journal of endocrinology2017, 7454376. https://doi.org/10.1155/2017/7454376

Testosterone

  1. Hackney, A.C., Lane, A.R. Low testosterone in male endurance-trained distance runners: impact of years in training. Hormones 17, 137–139 (2018). https://doi.org/10.1007/s42000-018-0010-z
  2. Popovic, B., Popovic, D., Macut, D., Antic, I. B., Isailovic, T., Ognjanovic, S., Bogavac, T., Kovacevic, V. E., Ilic, D., Petrovic, M., & Damjanovic, S. (2019). Acute Response to Endurance Exercise Stress: Focus on Catabolic/anabolic Interplay Between Cortisol, Testosterone, and Sex Hormone Binding Globulin in Professional Athletes. Journal of medical biochemistry38(1), 6–12. https://doi.org/10.2478/jomb-2018-0016
  3. Hooper, D. R., Tenforde, A. S., & Hackney, A. C. (2018). Treating exercise-associated low testosterone and its related symptoms. The Physician and sportsmedicine46(4), 427–434. https://doi.org/10.1080/00913847.2018.1507234
  4. Antonio L, Wu FC, O’Neill TW, et al. Low Free Testosterone Is Associated with Hypogonadal Signs and Symptoms in Men with Normal Total Testosterone. J Clin Endocrinol Metab. 2016;101(7):2647-2657. doi:10.1210/jc.2015-4106
  5. Beggs, L. A., Yarrow, J. F., Conover, C. F., Meuleman, J. R., Beck, D. T., Morrow, M., Zou, B., Shuster, J. J., & Borst, S. E. (2014). Testosterone alters iron metabolism and stimulates red blood cell production independently of dihydrotestosterone. American journal of physiology. Endocrinology and metabolism307(5), E456–E461. https://doi.org/10.1152/ajpendo.00184.2014
  6. Carrero, J. J., Bárány, P., Yilmaz, M. I., Qureshi, A. R., Sonmez, A., Heimbürger, O., Ozgurtas, T., Yenicesu, M., Lindholm, B., & Stenvinkel, P. (2012). Testosterone deficiency is a cause of anaemia and reduced responsiveness to erythropoiesis-stimulating agents in men with chronic kidney disease. Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association – European Renal Association27(2), 709–715. https://doi.org/10.1093/ndt/gfr288
  7. Hackney AC. Hypogonadism in Exercising Males: Dysfunction or Adaptive-Regulatory Adjustment? Front Endocrinol (Lausanne). 2020 Jan 31;11:11. doi: 10.3389/fendo.2020.00011. PMID: 32082255; PMCID: PMC7005256.
  8. Alves, J., Toro, V., Barrientos, G., Bartolomé, I., Muñoz, D., & Maynar, M. (2020). Hormonal Changes in High-Level Aerobic Male Athletes during a Sports Season. International journal of environmental research and public health, 17(16), 5833. https://doi.org/10.3390/ijerph17165833
  9. Bachman, E., Travison, T. G., Basaria, S., Davda, M. N., Guo, W., Li, M., Connor Westfall, J., Bae, H., Gordeuk, V., & Bhasin, S. (2014). Testosterone induces erythrocytosis via increased erythropoietin and suppressed hepcidin: evidence for a new erythropoietin/hemoglobin set point. The journals of gerontology. Series A, Biological sciences and medical sciences69(6), 725–735. https://doi.org/10.1093/gerona/glt154

OTS/RED-S

  1. Urhausen, A., Gabriel, H. & Kindermann, W. Blood Hormones as Markers of Training Stress and Overtraining. Sports Med. 20, 251–276 (1995). https://doi.org/10.2165/00007256-199520040-00004
  2. Meeusen, R., Duclos, M., Foster, C., Fry, A., Gleeson, M., Nieman, D., Raglin, J., Rietjens, G., Steinacker, J., Urhausen, A., European College of Sport Science, & American College of Sports Medicine (2013). Prevention, diagnosis, and treatment of the overtraining syndrome: joint consensus statement of the European College of Sport Science and the American College of Sports Medicine. Medicine and science in sports and exercise45(1), 186–205. https://doi.org/10.1249/MSS.0b013e318279a10a
  3. De Souza, M. J., Koltun, K. J., & Williams, N. I. (2019). The Role of Energy Availability in Reproductive Function in the Female Athlete Triad and Extension of its Effects to Men: An Initial Working Model of a Similar Syndrome in Male Athletes. Sports medicine (Auckland, N.Z.)49(Suppl 2), 125–137. https://doi.org/10.1007/s40279-019-01217-3
  4. Mountjoy, M., Sundgot-Borgen, J. K., Burke, L. M., Ackerman, K. E., Blauwet, C., Constantini, N., Lebrun, C., Lundy, B., Melin, A. K., Meyer, N. L., Sherman, R. T., Tenforde, A. S., Klungland Torstveit, M., & Budgett, R. (2018). IOC consensus statement on relative energy deficiency in sport (RED-S): 2018 update. British journal of sports medicine52(11), 687–697. https://doi.org/10.1136/bjsports-2018-099193
  5. Keay, N. What’s so good about Menstrual Cycles? British Journal of Sport and Exercise Medicine 2019
  6. Keay, N. Of Mice and Men (and Women) British Journal of Sport and Exercise Medicine 2019

Cortisol

  1. Skoluda, N., Dettenborn, L., Stalder, T., & Kirschbaum, C. (2012). Elevated hair cortisol concentrations in endurance athletes. Psychoneuroendocrinology37(5), 611–617. https://doi.org/10.1016/j.psyneuen.2011.09.001
  2. Perna, F. M., & McDowell, S. L. (1995). Role of psychological stress in cortisol recovery from exhaustive exercise among elite athletes. International journal of behavioral medicine2(1), 13–26. https://doi.org/10.1207/s15327558ijbm0201_2
  3. Harte, J. L., & Eifert, G. H. (1995). The effects of running, environment, and attentional focus on athletes’ catecholamine and cortisol levels and mood. Psychophysiology32(1), 49–54. https://doi.org/10.1111/j.1469-8986.1995.tb03405.x
  4. Popovic, B., Popovic, D., Macut, D., Antic, I. B., Isailovic, T., Ognjanovic, S., Bogavac, T., Kovacevic, V. E., Ilic, D., Petrovic, M., & Damjanovic, S. (2019). Acute Response to Endurance Exercise Stress: Focus on Catabolic/anabolic Interplay Between Cortisol, Testosterone, and Sex Hormone Binding Globulin in Professional Athletes. Journal of medical biochemistry, 38(1), 6–12. https://doi.org/10.2478/jomb-2018-0016

DHEA/OTS

  1. Bouget, M., Rouveix, M., Michaux, O., Pequignot, J. M., & Filaire, E. (2006). Relationships among training stress, mood and dehydroepiandrosterone sulphate/cortisol ratio in female cyclists. Journal of sports sciences24(12), 1297–1302. https://doi.org/10.1080/02640410500497790
  2. Filaire, E., Duché, P., & Lac, G. (1998). Effects of amount of training on the saliva concentrations of cortisol, dehydroepiandrosterone and on the dehydroepiandrosterone: cortisol concentration ratio in women over 16 weeks of training. European journal of applied physiology and occupational physiology, 78(5), 466–471. https://doi.org/10.1007/s004210050447
  3. Urhausen, A., Gabriel, H., & Kindermann, W. (1995). Blood hormones as markers of training stress and overtraining. Sports medicine (Auckland, N.Z.)20(4), 251–276. https://doi.org/10.2165/00007256-199520040-00004

Testing Frequency

  1. Lee, E. C., Fragala, M. S., Kavouras, S. A., Queen, R. M., Pryor, J. L., & Casa, D. J. (2017). Biomarkers in Sports and Exercise: Tracking Health, Performance, and Recovery in Athletes. Journal of strength and conditioning research31(10), 2920–2937. https://doi.org/10.1519/JSC.0000000000002122

BUN/CR/eGFR

  1. Hong, C. Z., & Lien, I. N. (1984). Metabolic effects of exhaustive training of athletes. Archives of physical medicine and rehabilitation65(7), 362–365.
  2. Fragala, M. S., Bi, C., Chaump, M., Kaufman, H. W., & Kroll, M. H. (2017). Associations of aerobic and strength exercise with clinical laboratory test values. PloS one, 12(10), e0180840. https://doi.org/10.1371/journal.pone.0180840

Bilirubin

  1. Fallon KE, Sivyer G, Sivyer K, Dare A. The biochemistry of runners in a 1600 km ultramarathon. Br J Sports Med. 1999 Aug;33(4):264-9. doi: 10.1136/bjsm.33.4.264. PMID: 10450482; PMCID: PMC1756186.
  2. Fragala, M. S., Bi, C., Chaump, M., Kaufman, H. W., & Kroll, M. H. (2017). Associations of aerobic and strength exercise with clinical laboratory test values. PloS one, 12(10), e0180840. https://doi.org/10.1371/journal.pone.0180840
  3. Witek, K., Ścisłowska, J., Turowski, D., Lerczak, K., Lewandowska-Pachecka, S., & Pokrywka, A. (2017). Total bilirubin in athletes, determination of reference range. Biology of sport34(1), 45–48. https://doi.org/10.5114/biolsport.2017.63732

AST/ALT

  1. Fallon KE, Sivyer G, Sivyer K, Dare A. The biochemistry of runners in a 1600 km ultramarathon. Br J Sports Med. 1999 Aug;33(4):264-9. doi: 10.1136/bjsm.33.4.264. PMID: 10450482; PMCID: PMC1756186
  2. Pettersson, J., Hindorf, U., Persson, P., Bengtsson, T., Malmqvist, U., Werkström, V., & Ekelund, M. (2008). Muscular exercise can cause highly pathological liver function tests in healthy men. British journal of clinical pharmacology65(2), 253–259. https://doi.org/10.1111/j.1365-2125.2007.03001.x
  3. Oh, R. C., & Hustead, T. R. (2011). Causes and evaluation of mildly elevated liver transaminase levels. American family physician84(9), 1003–1008.
  4. Banfi, G., Colombini, A., Lombardi, G., & Lubkowska, A. (2012). Metabolic markers in sports medicine. Advances in clinical chemistry56, 1–54. https://doi.org/10.1016/b978-0-12-394317-0.00015-7
    Lippi, G., Schena, F., Montagnana, M., Salvagno, G. L., Banfi, G., & Guidi, G. C. (2011). Significant variation of traditional markers of liver injury after a half-marathon run. European journal of internal medicine, 22(5), e36–e38. https://doi.org/10.1016/j.ejim.2011.02.007
  5. Fragala, M. S., Bi, C., Chaump, M., Kaufman, H. W., & Kroll, M. H. (2017). Associations of aerobic and strength exercise with clinical laboratory test values. PloS one, 12(10), e0180840. https://doi.org/10.1371/journal.pone.0180840

TSH

  1. Perseghin, G., Lattuada, G., Ragogna, F., Alberti, G., La Torre, A., & Luzi, L. (2009). Free leptin index and thyroid function in male highly trained athletes. European journal of endocrinology161(6), 871–876. https://doi.org/10.1530/EJE-09-0569
  2. Zarzeczny, R., Pilis, W., Langfort, J., Kaciuba-Uściłko, H., & Nazar, K. (1996). Influence of thyroid hormones on exercise tolerance and lactate threshold in rats. Journal of physiology and pharmacology : an official journal of the Polish Physiological Society47(3), 503–513.
  3. Meyer, T., & Meister, S. (2011). Routine blood parameters in elite soccer players. International journal of sports medicine, 32(11), 875–881. https://doi.org/10.1055/s-0031-1280776Nicoll, J. X., Hatfield, D. L., Melanson, K. J., & Nasin, C. S. (2018). Thyroid hormones and commonly cited symptoms of overtraining in collegiate female endurance runners. European journal of applied physiology118(1), 65–73. https://doi.org/10.1007/s00421-017-3723-9

SHBG

  1. Popovic, B., Popovic, D., Macut, D., Antic, I. B., Isailovic, T., Ognjanovic, S., Bogavac, T., Kovacevic, V. E., Ilic, D., Petrovic, M., & Damjanovic, S. (2019). Acute Response to Endurance Exercise Stress: Focus on Catabolic/anabolic Interplay Between Cortisol, Testosterone, and Sex Hormone Binding Globulin in Professional Athletes. Journal of medical biochemistry38(1), 6–12. https://doi.org/10.2478/jomb-2018-0016
  2. Sönksen, P.H., Holt, R.I.G., Böhning, W. et al. Why do endocrine profiles in elite athletes differ between sports?. Clin Diabetes Endocrinol 4, 3 (2018). https://doi.org/10.1186/s40842-017-0050-3

Glucose

  1. Brun, J. F., Dumortier, M., Fedou, C., & Mercier, J. (2001). Exercise hypoglycemia in nondiabetic subjects. Diabetes & metabolism27(2 Pt 1), 92–106.
  2. Kuipers, H., Fransen, E. J., & Keizer, H. A. (1999). Pre-exercise ingestion of carbohydrate and transient hypoglycemia during exercise. International journal of sports medicine20(4), 227–231. https://doi.org/10.1055/s-2007-971122

ABT.she

Effects of Menstrual Cycle 

  1. The effect of the menstrual cycle on exercise metabolism: implications for exercise performance in eumenorrhoeic women. 2010
  2. Menstrual cycle phase and sex influence muscle glycogen utilization and glucose turnover during moderate-intensity endurance exercise. 2006
  3. Effects of menstrual cycle phase on athletic performance. 1995
  4. Menstrual cycle: no effect on exercise cardiorespiratory variables or blood lactate concentration. 2007
  5. Circadian rhythms, sleep, and the menstrual cycle. 2007
  6. Antioxidant protection during the menstrual cycle: the effects of estradiol on ascorbic-dehydroascorbic acid plasma levels and total antioxidant plasma status in eumenorrhoic women during the menstrual cycle. 2006
  7. Changes in bone resorption during the menstrual cycle.1999
  8. Menstrual cycle rhythmicity: metabolic patterns in healthy women. 2018
  9. Cyclic fluctuations in human serum lipid and apolipoprotein levels during the normal menstrual cycle: comparison with changes occurring during oral contraceptive therapy. 1991
  10. MRI reveals menstrually-related muscle edema that negatively affects athletic agility in young women. 2018
  11. Changes in macronutrient, micronutrient, and food group intakes throughout the menstrual cycle in healthy, premenopausal women. 2016 
  12. Effect of Menstrual Cycle Phases on Plasma Lipid and Lipoprotein Levels in Regularly Menstruating Women. 2017
  13. The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis 2020
  14. https://www.researchgate.net/publication/328294878_On_exercise_thermoregulation_in_females_interaction_of_endogenous_and_exogenous_ovarian_hormones 

Micronutrient Changes Across the Cycle 

  1. Iron regulation in athletes: exploring the menstrual cycle and effects of different exercise modalities on hepcidin production 2014
  2. Variations in iron-status measures during the menstrual cycle. 1993
  3. alpha-Tocopherol concentrations in plasma but not in lipoproteins fluctuate during the menstrual cycle in healthy premenopausal women. 1998
  4. Effect of menstrual cycle phase on the concentration of individual carotenoids in lipoproteins of premenopausal women: a controlled dietary study. 1998
  5. Analytical and biological variation of biomarkers of oxidative stress during the menstrual cycle. 2008
  6. vitamin D metabolite across the menstrual cycle: a systematic review 2019
  7. vitamin D and reproductive hormones across the menstrual cycle 2020
  8. folate, homocysteine and the ovarian cycle among healthy regularly menstruating women
  9. Changes in copper and zinc plasma concentrations during the normal menstrual cycle in women. 2010
  10. variations in plasma volume and micronutrient biomarkers across the menstrual cycle 2019 *it’s a dissertation, not a published manuscript but still useful

Minimizing PMS 

  1. A Pilot Randomized Treatment-Controlled Trial Comparing Vitamin B6 with Broad-Spectrum Micronutrients for Premenstrual Syndrome. 2020
  2. A lecithin phosphatidylserine and phosphatidic acid complex (PAS) reduces symptoms of the premenstrual syndrome (PMS): Results of a randomized, placebo-controlled, double-blind clinical trial. 2018
  3. *do not recommend women take St. John’s Wart for PMS management, shown to decrease ovarian follicle counts in a dose-dependant manner https://www.ncbi.nlm.nih.gov/pubmed/29755030
  4. Vitex agnus castus for premenstrual syndrome and premenstrual dysphoric disorder: a systematic review. 2017
  5. Micronutrients and the Premenstrual Syndrome: The Case for Calcium 2000
  6. The Potential for Dietary Supplements to Reduce Premenstrual Syndrome (PMS) Symptoms 2000 (spoiler alert, only Ca has strong evidence)
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  2. Simon Reinke et al., “Absolute and Functional Iron Deficiency in Professional Athletes during Training and Recovery.,” International Journal of Cardiology 156, no. 2 (April 19, 2012): 186–91, https://doi.org/10.1016/j.ijcard.2010.10.139.
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  14. David Montero et al., “Erythropoiesis with Endurance Training: Dynamics and Mechanisms.,” American Journal of Physiology. Regulatory, Integrative and Comparative Physiology312, no. 6 (June 1, 2017): R894–902, https://doi.org/10.1152/ajpregu.00012.2017.
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  16. Tamara Hew-Butler et al., “Exercise-Associated Hyponatremia: 2017 Update.,” Frontiers in Medicine 4 (2017): 21, https://doi.org/10.3389/fmed.2017.00021.
  17. Emmanuelle Varlet-Marie et al., “Exercise-Induced Changes in Hematocrit and Hematocrit/Viscosity Ratio in Male Rugby Players.,” Clinical Hemorheology and Microcirculation 64, no. 4 (2016): 817–26, https://doi.org/10.3233/CH-168042.
  18. James P. McClung, Erin Gaffney-Stomberg, and Jane J. Lee, “Female Athletes: A Population at Risk of Vitamin and Mineral Deficiencies Affecting Health and Performance.,” Journal of Trace Elements in Medicine and Biology : Organ of the Society for Minerals and Trace Elements (GMS) 28, no. 4 (October 2014): 388–92, https://doi.org/10.1016/j.jtemb.2014.06.022.
  19. J. A. Smith et al., “Greater Erythrocyte Deformability in World-Class Endurance Athletes.,” The American Journal of Physiology 276, no. 6 (June 1999): H2188-2193, https://doi.org/10.1152/ajpheart.1999.276.6.H2188.
  20. David Montero et al., “Haematological Rather than Skeletal Muscle Adaptations Contribute to the Increase in Peak Oxygen Uptake Induced by Moderate Endurance Training.,” The Journal of Physiology 593, no. 20 (October 15, 2015): 4677–88, https://doi.org/10.1113/JP270250.
  21. Michael R. Baria et al., “High Intensity Interval Exercise Increases Platelet and Transforming Growth Factor-Beta Yield in Platelet-Rich Plasma.,” PM & R : The Journal of Injury, Function, and Rehabilitation 12, no. 12 (December 2020): 1244–50, https://doi.org/10.1002/pmrj.12368.
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  23. Alexander T. Carswell et al., “Influence of Vitamin D Supplementation by Sunlight or Oral D3 on Exercise Performance.,” Medicine and Science in Sports and Exercise 50, no. 12 (December 2018): 2555–64, https://doi.org/10.1249/MSS.0000000000001721.
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