ISO Fit is a product from Austrian based company Natural Power. The product description stats that this product is designed for athletes in pre competition or in competition to avoid muscle cramps and power loss. This review will aim to understand how these ingredients can achieve these claims.

Dextrose

Dextrose is a fast absorbing carbohydrate that gives a quick release of energy. It is usually found in supplements as its properties mix very well with other substances.

Sodium chloride

Sodium chloride is otherwise known as salt. It is theorised that sodium chloride can help prevent cramps as the key mechanism in muscle contraction is the flooding of the action potential in the muscle membrane, and so if there is a sodium deficiency it may cause the muscle to cramp (1).

Magnesium gluconate

Magnesium gluconate does not induce any nutritional benefits. The main reason for this substance being in the supplement is that it is a lubricant for the machinery that manufactures the product.

Calcium lactate

Calcium lactate has been found to treat and prevent calcium deficiencies as it helps aid bone formation and density. Research has not found this substance to be effective, (2), however more studies are needed to determine this.

Ascorbic acid (vitamin C)

Vitamin C is known to be a powerful antioxidant (3). Studies have suggested that it can increase endothelial nitric oxide by protecting it from oxidation and increase synthesis, another function that Vitamin C has suggested includes reducing blood pressure (4), however the only proven function of vitamin C is the prevention of scurvy (5).

Nicotinamide (niacin)

Niacin is otherwise known as vitamin B3 and in an antioxidant. Research studies have shown that niacin supplementation increases growth hormones in response to anaerobic exercise (6) as well as a reduction in fasting triglycerides (7). An increase in fasting insulin has been found due to a decrease in insulin sensitivity (8). Further research is needed for this supplement in order to understand the mechanisms.

DL-alpha-tocopherol acetate 50% (vitamin E)

Dl-alpha tocopheryl acetate is otherwise known as vitamin E and is an antioxidant (9). This means that it protects the muscles from free radicals, which causes muscle soreness and damage to the muscle tissue and fat cells (10). Dl-alpha tocopheryl acetate can counteract these free radicals before damaging these parts of the body which can allow exercise to be prolonged (11).

Calcium D-pantothenate (pantothenic acid)

Calcium D-pantothenate (pantothenic acid) is otherwise known as vitamin B5 and is water soluble. This ingredient helps keep a healthy digestive tract (12) and uses vitamin B2 (13). Pantothenic acid has pantethine which has been found to lower cholesterol (14).

Pyridoxine hydrochloride (Vitamin B6)

The active form of vitamin B6 is known as P-L-P (15), which is stimulated by exercise (16). During exercise the body relies on the liver to produce glucose via glycogenolysis, for which vitamin b6 is essential for, and is an integral part of the glycogen phosphorylase enzyme and thus will provide energy to the bodies’ muscles (17).

Riboflavin (Vitamin B2)

Riboflavin is a nutrient that has been found to help in fat metabolism via the electron-transport chain (18) and an antioxidant (19). It is also one of many nutrients that helps in the production of red blood cells. Levels of riboflavin has been found to diminish during exhaustive exercise (20).

Thiamine Mononitrate (Vitamin B1)

Thiamine is also known as vitamin B1 (21) is an essential role in carbohydrate metabolism and oxidation (22). The reported effect that have been found includes, a decrease in heart rate, blood glucose and lactate concentrations (23).

Folic Acid

Folic acid is also known as folate is a water soluble mineral that, along with other nutrients is necessary for red blood cell production (24). It can also help regulate nitric oxide levels in the blood (25).

Biotin

Biotin can also be know as vitamin B7 or Vitamin H. it has been found that it can contribute to metabolism and cell development (26) as well as providing energy during exercise (27).

Cyanocobalamin 0.1% (vitamin B12)

Research studies on vitamin B12 have found that it is required for red blood cell production (28), Protein synthesis and the repair and maintenance of tissue cells. (29).

Calcium citrate

Calcium citrate is used as a preservative, a food additive that enhances the flavour and regulates acidity.

Magnesium Stearate

Magnesium stearate does not induce any nutritional benefits. The main reason for this substance being in the supplement is that it is a lubricant for the machinery that manufactures the product.

Calcium carbonate

Calcium carbonate is used as an acidity regulator, anticaking agent, stabiliser or colour.

Maltodextrin

Maltodextrin is a polysaccharide which is a complex carbohydrate. This ingredient is water soluble and unlike other carbohydrates, is easily digestible (30) and can give a quick release of energy without any spikes of glycaemia (31).

Zinc gluconate

Zinc gluconate is used to help aid in the growth and development of body tissue (32) as well as a variety of biological processes including wound healing and muscle cramps (33). Zinc supplementation has also been found to improve muscle strength and endurance (34)

Ferric pyrophosphate

Ferric pyrophosphate is a water – insoluble iron compound which is used to fortify ingredients (35).

Citric acid

The main function of citric acid is the reduction of physical fatigue (36). The reason for this is due to citric acid being a major component of the tricarboxylic acid (TCA) cycle. TCA cycle is the process of converting carbohydrates, fats and proteins into carbon dioxide and water (37). By increasing citric acid it activates the TCA cycle and in turn speeds up ATP production thus replenishing energy.

Natural pineapple aroma

Natural pineapple aroma is used to enhance the flavour of the product.

Acesulfame K

Acesulfame K is a sweetener that is calorie free. This ingredient is used in many products and is used to make the product taste sweeter and does not have any nutritional benefit.  

Sucralose

Sucralose is a sweetener that is calorie free. This ingredient is used in many products and is used to make the product taste sweeter and does not have any nutritional benefit.

Riboflavin Dye

Riboflavin is a nutrient that has been found to help in fat metabolism via the electron-transport chain (38) and an antioxidant (39). It is also one of many nutrients that helps in the production of red blood cells. Levels of riboflavin has been found to diminish during exhaustive exercise (40).

The wide variety of ingredients in this product enables this product to maintain muscle mass and aid in recovery. In addition to this it also contains antioxidant properties. This supplement is recommended to be taken post workout. This product has no banned substances when referring to the WADA prohibited list when observing the label/ ingredients posted on the website.

*NOTE – This product has not been tested in a laboratory and may contain other substances that may not appear on the label abel

1 – McCance, R. A. (1936). Experimental sodium chloride deficiency in man.Proceedings of the Royal Society of London. Series B, Biological Sciences,119(814), 245-268.

2 – Young, G., & Jewell, D. (2002). Interventions for leg cramps in pregnancy. The Cochrane Library.

3 – Kalt, W., Forney, C. F., Martin, A., & Prior, R. L. (1999). Antioxidant capacity, vitamin C, phenolics, and anthocyanins after fresh storage of small fruits.Journal of Agricultural and Food Chemistry, 47(11), 4638-4644.

4 – Huang, A., Vita, J. A., Venema, R. C., & Keaney, J. F. (2000). Ascorbic acid enhances endothelial nitric-oxide synthase activity by increasing intracellular tetrahydrobiopterin. Journal of biological chemistry, 275(23), 17399-17406.

5 – Padayatty, S. J., Katz, A., Wang, Y., Eck, P., Kwon, O., Lee, J. H., … & Levine, M. (2003). Vitamin C as an antioxidant: evaluation of its role in disease prevention. Journal of the American College of Nutrition, 22(1), 18-35.

6 – Stokes, K. A., Tyler, C., & Gilbert, K. L. (2008). The growth hormone response to repeated bouts of sprint exercise with and without suppression of lipolysis in men. Journal of Applied Physiology, 104(3), 724-728.

7  – Plaisance, E. P., Mestek, M. L., Mahurin, A. J., Taylor, J. K., Moncada-Jimenez, J., & Grandjean, P. W. (2008). Postprandial triglyceride responses to aerobic exercise and extended-release niacin. The American journal of clinical nutrition, 88(1), 30-37.

8 – Vega, G. L., Cater, N. B., Meguro, S., & Grundy, S. M. (2005). Influence of extended-release nicotinic acid on nonesterified fatty acid flux in the metabolic syndrome with atherogenic dyslipidemia. The American journal of cardiology, 95(11), 1309-1313.

9 – Jakemanl, P., & Maxwell, S. (1993). Effect of antioxidant vitamin supplementation on muscle function after eccentric exercise. European journal of applied physiology and occupational physiology, 67(5), 426-430.

10 – Davies, K. J., Quintanilha, A. T., Brooks, G. A., & Packer, L. (1982). Free radicals and tissue damage produced by exercise. Biochemical and biophysical research communications, 107(4), 1198-1205.

11 – McCay, P. B. (1985). Vitamin E: interactions with free radicals and ascorbate.Annual review of nutrition, 5(1), 323-340.

12 – Millman, P. L. (1989). U.S. Patent No. 4,871,550. Washington, DC: U.S. Patent and Trademark Office.

13 – Blake, C. J. (2007). Analytical procedures for water-soluble vitamins in foods and dietary supplements: a review. Analytical and bioanalytical chemistry,389(1), 63-76.

14 – Hendler SS, Rorvik DR, eds. PDR for Nutritional Supplements. Montvale: Medical Economics Company, Inc; 2001

15 – Ubbink, J. B., Vermaak, W. J., van der Merwe, A., & Becker, P. J. (1993). Vitamin B-12, vitamin B-6, and folate nutritional status in men with hyperhomocysteinemia. The American journal of clinical nutrition, 57(1), 47-53.

16 – Manore, M. M. (2000). Effect of physical activity on thiamine, riboflavin, and vitamin B-6 requirements. The American journal of clinical nutrition, 72(2), 598s-606s.

17 – Manore, M. N., Leklem, J. E., & Walter, M. C. (1987). Vitamin B-6 metabolism as affected by exercise in trained and untrained women fed diets differing in carbohydrate and vitamin B-6 content. The American journal of clinical nutrition,46(6), 995-1004.

18 – Powers, H. J. (2003). Riboflavin (vitamin B-2) and health. The American journal of clinical nutrition, 77(6), 1352-1360.

19 – Sugiyama, M. (1992). Role of physiological antioxidants in chromium (VI)-induced cellular injury. Free Radical Biology and Medicine, 12(5), 397-407.

20 – Belko, A. Z., Obarzanek, E., Roach, R., Rotter, M., Urban, G., Weinberg, S., & Roe, D. A. (1984). Effects of aerobic exercise and weight loss on riboflavin requirements of moderately obese, marginally deficient young women. The American journal of clinical nutrition, 40(3), 553-561.

21 – Webster, M. J., Scheett, T. P., Doyle, M. R., & Branz, M. (1997). The effect of a thiamin derivative on exercise performance. European journal of applied physiology and occupational physiology, 75(6), 520-524.

22 – Davis, R. E., & Icke, G. C. (1983). Clinical chemistry of thiamin. Advances in clinical chemistry, 23, 93.

23 – Knippel, M., Mauri, L., Belluschi, R., Bana, G., Galli, C., Pusterla, G. L., . & Troina, E. (1986). The action of thiamin on the production of lactic acid in cyclists. Med Sport, 39(1), 11.

24 – Choumenkovitch, S. F., Jacques, P. F., Nadeau, M. R., Wilson, P. W., Rosenberg, I. H., & Selhub, J. (2001). Folic acid fortification increases red blood cell folate concentrations in the Framingham study. The Journal of nutrition,131(12), 3277-3280.

25 – Stroes, E. S. G., Van Faassen, E. E., Yo, M., Martasek, P., Boer, P., Govers, R., & Rabelink, T. J. (2000). Folic acid reverts dysfunction of endothelial nitric oxide synthase. Circulation research, 86(11), 1129-1134.

26 – Barone, S. (1988). Vitamins and athletes. In Drugs, Athletes, and Physical Performance (pp. 1-9). Springer US.

27 – Lukaski HC. Vitamin and mineral status: effects on physical performance. Nutrition. 2004;20:632-44

28 – d’Onofrio, G., Chirillo, R., Zini, G., Caenaro, G., Tommasi, M., & Micciulli, G. (1995). Simultaneous measurement of reticulocyte and red blood cell indices in healthy subjects and patients with microcytic and macrocytic anemia. Blood,85(3), 818-823.

29 – Fenech, M. (2001). The role of folic acid and vitamin B12 in genomic stability of human cells. Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, 475(1), 57-67.

30 – Haralampu, S. G. (2000). Resistant starch—a review of the physical properties and biological impact of RS< sub> 3</sub>. Carbohydrate polymers, 41(3), 285-292.

31 – Roberts, M., Lockwood, C., Dalbo, V. J., Tucker, P., Frye, A., Polk, R., … & Kerksick, C. (2009). Ingestion of a high molecular weight modified waxy maize starch alters metabolic responses to prolonged exercise in trained cyclists. In FASEB abstract.

32 – Hashemipour, M., Kelishadi, R., Shapouri, J., Sarrafzadegan, N., Amini, M., Tavakoli, N., … & Poursafa, P. (2009). Effect of zinc supplementation on insulin resistance and components of the metabolic syndrome in prepubertal obese children. Hormones (Athens), 8(4), 279-285.

33 – Prasad, A. S. (1991). Discovery of human zinc deficiency and studies in an experimental human model. The American journal of clinical nutrition, 53(2), 403-412.

34 – Kugelmas, M. (2000). Preliminary observation: oral zinc sulfate replacement is effective in treating muscle cramps in cirrhotic patients. Journal of the American College of Nutrition, 19(1), 13-15.

35 – Fidler, M. C., Walczyk, T., Davidsson, L., Zeder, C., Sakaguchi, N., Juneja, L. R., & Hurrell, R. F. (2004). A micronised, dispersible ferric pyrophosphate with high relative bioavailability in man. British Journal of Nutrition, 91(01), 107-112.

36 – Sugino, T., Aoyagi, S., Shirai, T., Kajimoto, Y., & Kajimoto, O. (2007). Effects of citric acid and L-carnitine on physical fatigue. Journal of clinical biochemistry and nutrition, 41(3), 224.

37 – Baldwin, J. E., & Krebs, H. (1981). The evolution of metabolic cycles.

38 – Powers, H. J. (2003). Riboflavin (vitamin B-2) and health. The American journal of clinical nutrition, 77(6), 1352-1360.

39 – Sugiyama, M. (1992). Role of physiological antioxidants in chromium (VI)-induced cellular injury. Free Radical Biology and Medicine, 12(5), 397-407.

40 – Belko, A. Z., Obarzanek, E., Roach, R., Rotter, M., Urban, G., Weinberg, S., & Roe, D. A. (1984). Effects of aerobic exercise and weight loss on riboflavin requirements of moderately obese, marginally deficient young women. The American journal of clinical nutrition, 40(3), 553-561.