The ingredients in RunStrong have been subject to extensive research and testing. Below is a list of reputable studies detailing the effects of each of these ingredients in various types of sport and in regard to other health benefits.

L-Carnitine L-Tartrate / Carnipure®

1. L-Carnitine Tartrate Supplementation for 5 weeks Improves Exercise Recovery in Men and Women: A Randomized, Double-Blind, Placebo-Controlled Trial. https://doi.org/10.3390/nu13103432
2. Influence of L-carnitine administration on maximal physical exercise.  https://doi.org/10.1007/BF00236072
3. Supplementation of L-carnitine in athletes: does it make sense? https://doi.org/10.1016/j.nut.2004.04.003
4. The effects of acute L-carnitine supplementation on endurance performance of athletes. https://doi.org/10.1519/JSC.0b013e3182a76790
5. l-Carnitine Supplementation in Recovery after Exercise. https://doi.org/10.3390/nu10030349
6. L-Carnitine L-tartrate supplementation favorably affects markers of recovery from exercise stress. https://doi.org/10.1152/ajpendo.00277.2001
7. Responses of criterion variables to different supplemental doses of L-carnitine L-tartrate. https://doi.org/10.1519/00124278-200702000-00046
8. Effects of nine weeks L-Carnitine supplementation on exercise performance, anaerobic power, and exercise-induced oxidative stress in resistance-trained males.  https://doi.org/10.20463/jenb.2018.0026
9. Chronic oral ingestion of L-carnitine and carbohydrate increases muscle carnitine content and alters muscle fuel metabolism during exercise in humans.  https://doi.org/10.1113/jphysiol.2010.201343
10. Effects of L-carnitine on the pyruvate dehydrogenase complex and carnitine palmitoyl transferase activities in muscle of endurance athletes.  https://doi.org/10.1016/0014-5793(94)80246-7
11. Respiratory chain enzymes in muscle of endurance athletes: effect of L-carnitine. https://doi.org/10.1016/0006-291x(92)92355-2
12. The effects of acute L-carnitine supplementation on endurance performance of athletes. https://doi.org/10.1519/JSC.0b013e3182a76790
13. A Dose-Dependent Effect of Carnipure Tartrate Supplementation on Endurance Capacity, Recovery, and Body Composition in an Exercise Rat Model. https://doi.org/10.3390/nu12051519
14. Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis. https://doi.org/10.1016/j.clnesp.2020.03.008
15. An acute increase in skeletal muscle carnitine content alters fuel metabolism in resting human skeletal muscle. https://doi.org/10.1210/jc.2006-1584
16. New insights concerning the role of carnitine in the regulation of fuel metabolism in skeletal muscle. https://doi.org/10.1113/jphysiol.2006.125799
17. Skeletal muscle carnitine loading increases energy expenditure, modulates fuel metabolism gene networks and prevents body fat accumulation in humans. https://doi.org/10.1113/jphysiol.2013.255364
18. The Effects Of L-carnitine And Exercise On Health Risk Factors In Obese High-school Girls. doi: 10.1249/01.MSS.0000385004.59061.93
19. The effects of L-carnitine L-tartrate supplementation on hormonal responses to resistance exercise and recovery.  https://doi.org/10.1519/1533-4287(2003)017<0455:teolls>2.0.co;2
20. Effects of prolonged L-carnitine administration on delayed muscle pain and CK release after eccentric effort. https://doi.org/10.1055/s-2007-972854
21. l-Carnitine l-tartrate supplementation favorably affects biochemical markers of recovery from physical exertion in middle-aged men and women.  https://doi.org/10.1016/j.metabol.2009.11.012
22. Carnitine in muscle, serum, and urine of nonprofessional athletes: effects of physical exercise, training, and L-carnitine administration. https://doi.org/10.1002/mus.880140703

1. Curcumin supplementation likely attenuates delayed onset muscle soreness (DOMS). https://doi.org/10.1007/s00421-015-3152-6
2. Modulation of Exercise-Induced Muscle Damage, Inflammation, and Oxidative Markers by Curcumin Supplementation in a Physically Active Population: A Systematic Review. https://doi.org/10.3390/nu12020501
3. Effects of oral curcumin ingested before or after eccentric exercise on markers of muscle damage and inflammation.  https://doi.org/10.1111/sms.13373
4. The effect of curcumin supplementation on recovery following exercise-induced muscle damage and delayed-onset muscle soreness: A systematic review and meta-analysis of randomized controlled trials.  https://doi.org/10.1002/ptr.6912
5. Effects of curcumin supplementation on sport and physical exercise: a systematic review. https://doi.org/10.1080/10408398.2020.1749025
6. Curcumin effects on inflammation and performance recovery following eccentric exercise-induced muscle damage. https://doi.org/10.1152/ajpregu.00858.2006
7. Curcumin: A Review of Its Effects on Human Health. https://doi.org/10.3390/foods6100092
8. Effects of curcumin supplementation on sport and physical exercise: a systematic review. https://doi.org/10.1080/10408398.2020.1749025
9. Antioxidant and anti-inflammatory properties of curcumin.  https://doi.org/10.1007/978-0-387-46401-5_3
10. Curcumin, inflammation, ageing and age-related diseases. Immunity & ageing https://doi.org/10.1186/1742-4933-7-1
11. Safety and efficacy of curcumin versus diclofenac in knee osteoarthritis: a randomized open-label parallel-arm study. https://doi.org/10.1186/s13063-019-3327-2
12. The Effects of Eight Weeks Interval Training and Curcumin Consumption on TNF-α and BDNF Levels in Men with Metabolic Syndrome. http://jarums.arums.ac.ir/article-1-1451-en.html
13. Nonsteroidal anti-inflammatory agents differ in their ability to suppress NF-kappaB activation, inhibition of expression of cyclooxygenase-2 and cyclin D1, and abrogation of tumor cell proliferation. https://doi.org/10.1038/sj.onc.1208169
14. Turmeric and Its Major Compound Curcumin on Health: Bioactive Effects and Safety Profiles for Food, Pharmaceutical, Biotechnological and Medicinal Applications.  https://doi.org/10.3389/fphar.2020.01021
15. Curcumin ingestion and exercise training improve vascular endothelial function in postmenopausal women. https://doi.org/10.1016/j.nutres.2012.09.002
16. Oxidative stress: role of physical exercise and antioxidant nutraceuticals in adulthood and aging. https://doi.org/10.18632/oncotarget.24729
17. Dietary Supplements for Health, Adaptation, and Recovery in Athletes. http://journals.humankinetics.com/view/journals/ijsnem/28/2/article-p188.xml
18. A randomized, pilot study to assess the efficacy and safety of curcumin in patients with active rheumatoid arthritis. https://doi.org/10.1002/ptr.4639
19. Reflections about Osteoarthritis and Curcuma longa.  https://doi.org/10.4103/phrev.phrev_54_16
20. Evaluation of the protective effects of curcuminoid (curcumin and bisdemethoxycurcumin)-loaded liposomes against bone turnover in a cell-based model of osteoarthritis. https://doi.org/10.2147/DDDT.S78277
21. Efficacy of Turmeric Extracts and Curcumin for Alleviating the Symptoms of Joint Arthritis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. https://doi.org/10.1089/jmf.2016.3705
22. Curcumin and obesity. https://doi.org/10.1002/biof.1074
23. Turmeric extract and its active compound, curcumin, protect against chronic CCl4-induced liver damage by enhancing antioxidation. BMC complementary and alternative medicine. https://doi.org/10.1186/s12906-016-1307-6
24. Curcumin supplementation likely attenuates delayed onset muscle soreness (DOMS). https://doi.org/10.1007/s00421-015-3152-6
25. Therapeutic effects of turmeric or curcumin extract on pain and function for individuals with knee osteoarthritis: a systematic review. https://bmjopensem.bmj.com/content/7/1/e000935
26. Curcumin Improves Delayed Onset Muscle Soreness And Postexercise Lactate Accumulation. https://doi.org/10.1080/19390211.2020.1796885
27. Reduced inflammatory and muscle damage biomarkers following oral supplementation with bioavailable curcumin. https://doi.org/10.1016/j.bbacli.2016.02.003
28. Potential role of bioavailable curcumin in weight loss and omental adipose tissue decrease: preliminary data of a randomized, controlled trial in overweight people with metabolic syndrome. Preliminary study. https://pubmed.ncbi.nlm.nih.gov/26592847
29. Curcumin limits weight gain, adipose tissue growth, and glucose intolerance following the cessation of exercise and caloric restriction in rats. https://pubmed.ncbi.nlm.nih.gov/28839007
30. Curcumin rescues high fat diet-induced obesity and insulin sensitivity in mice through regulating SREBP pathway. https://pubmed.ncbi.nlm.nih.gov/27208389

1. Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers. https://doi.org/10.1055/s-2006-957450
2. Curcumin: A Review of Its Effects on Human Health. Foods https://doi.org/10.3390/foods6100092
3. Iron and Physical Activity: Bioavailability Enhancers, Properties of Black Pepper (Bioperine®) and Potential Applications. https://doi.org/10.3390/nu12061886
4. Piperine and Its Role in Chronic Diseases. https://doi.org/10.1007/978-3-319-41334-1_8
5. Piper nigrum and piperine: an update. Phytotherapy research. https://doi.org/10.1002/ptr.4972
6. Anti-inflammatory and antiarthritic effects of piperine in human interleukin 1beta-stimulated fibroblast-like synoviocytes and in rat arthritis models. https://doi.org/10.1186/ar2662

1. Is iron treatment beneficial in, iron-deficient but non-anaemic (IDNA) endurance athletes? A systematic review and meta-analysis. https://doi.org/10.1136/bjsports-2014-093624
2. Iron and Physical Activity: Bioavailability Enhancers, Properties of Black Pepper (Bioperine®) and Potential Applications. https://doi.org/10.3390/nu12061886
3. Efficacy of iron supplementation on fatigue and physical capacity in non-anaemic iron-deficient adults: a systematic review of randomised controlled trials. https://doi.org/10.1136/bmjopen-2017-019240
4. Iron Bisglycinate Chelate and Polymaltose Iron for the Treatment of Iron Deficiency Anemia: A Pilot Randomized Trial. https://doi.org/10.2174/1573396314666181002170040
5. Iron considerations for the athlete: a narrative review. https://doi.org/10.1007/s00421-019-04157-y
6. Effects of iron repletion on blood volume and performance capacity in young athletes. https://doi.org/10.1097/00005768-200105000-00010
7. Recent Advances in Iron Metabolism: Relevance for Health, Exercise, and Performance. https://doi.org/10.1249/MSS.0000000000000593
8. Foot-strike haemolysis in an ultramarathon runner. https://doi.org/10.1136/bcr-2017-220661
9. Runner's anemia. https://doi.org/10.1001/jama.286.6.714
10. Footstrike is the major cause of hemolysis during running.  https://doi.org/10.1152/japplphysiol.00631.2001
11. Sport-related hematuria: a review. https://doi.org/10.1097/00042752-199704000-00008
12. Iron deficiency in sports - definition, influence on performance and therapy. https://doi.org/10.4414/smw.2015.14196
13. Iron supplementation benefits physical performance in women of reproductive age: a systematic review and meta-analysis. https://doi.org/10.3945/jn.113.189589
14. Treatment of iron deficiency anemia induces weight loss and improves metabolic parameters. https://pubmed.ncbi.nlm.nih.gov/24770833

1. Dietary Supplements for Health, Adaptation, and Recovery in Athletes.http://journals.humankinetics.com/view/journals/ijsnem/28/2/article-p188.xml 
2. The Effect of Abnormal Vitamin D Levels in Athletes. https://doi.org/10.7812/TPP/17-216
3. Sports Health Benefits of Vitamin D. https://doi.org/10.1177/1941738112461621
4. The effects of indoor and outdoor sports participation and seasonal changes on vitamin D levels in athletes. https://doi.org/10.1177/2050312119837480
5. Role of Vitamin D in Athletes and Their Performance: Current Concepts and New Trends. https://doi.org/10.3390/nu12020579
6. Vitamin D and the Immune System. https://doi.org/10.2310/JIM.0b013e31821b8755
7. Vitamin D and bone health: potential mechanisms. https://doi.org/10.3390/nu2070693
8. Evaluating the relationship of calcium and vitamin D in the prevention of stress fracture injuries in the young athlete: a review of the literature. https://doi.org/10.1016/j.pmrj.2010.05.006
9. Short and long-term variations in serum calciotropic hormones after a single very large dose of ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3) in the elderly. https://doi.org/10.1210/jc.2008-0350
10. Vitamin D and the immune system. https://doi.org/10.2310/JIM.0b013e31821b8755
11. Vitamin D and adipogenesis: new molecular insights. https://pubmed.ncbi.nlm.nih.gov/18254883
12. Vitamin D decreases adipocyte lipid storage and increases NAD-SIRT1 pathway in 3T3-L1 adipocytes. https://pubmed.ncbi.nlm.nih.gov/26899162
13. Optimal vitamin D spurs serotonin: 1,25-dihydroxyvitamin D represses serotonin reuptake transport (SERT) and degradation (MAO-A) gene expression in cultured rat serotonergic neuronal cell lines. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6042449/