Fit Protein is a product from Austrian based company Natural Power. The description of this product states that it supports fat metabolism and can give firmer muscles. This review will delve into the research that has looked into these ingredients to understand how this product can achieve the outcomes described.

Whey Protein Concentrate / Soy Isolate

Whey protein, soy and sodium caseinate helps aid muscle protein synthesis when combined with resistance training (1, 2). Other key features include increasing muscle mass (3), an increase in lean body mass (4) and greater recovery from exercise (5). Longer periods of supplementation have shown greater gains in fat free mass (6).

Muscle protein synthesis is increased due to high concentration of Leucine (BCAA) which is a signalling molecule needed to increase muscle protein synthesis (7). Consumption of protein helps increase muscle mass due to a greater amount of peripheral nitrogen retention whereas soy protein has been found to have a greater effect on splanchnic protein synthesis (8).

The reason for greater recovery of exercise can be due to a post exercise insulin response (9, 10) which means glycogen resynthesis occurs rapidly so exercise can be prolonged, with greater training volume increased hypertrophy and decreased muscle damage.

L-glycine

Glycine is one of the components of creatine which helps increase muscle growth and energy during exercise (11). When metabolised it acts as an amino acid and regulates blood sugar levels which can also control that amount of sugar released into the blood (12).

Wheat gluten

Wheat gluten is the main protein of wheat. A desired property of gluten is its ability to bind fat and water while at the same time increasing the protein content (13).

Natural strawberry flavour

Natural strawberry flavour is used to enhance the flavour of this sport supplement.

L-carnitine

L-Carnitine is a dipeptide made from the essential amino acids lysine and methionine. L-Carnitine plays an important role in fat metabolism by allowing long chained fatty acids to pass through the mitochondrial membrane (14, 15).

Guar gum

Guar gum is a dietary fibre that has been reported to decrease plasma cholesterol concentration (16) and increased satiety (17). However a meta-analysis found that although this product is safe no benefit has been found compared to a placebo (18).

Xanthan gum

Xanthan Gum are water soluble dietary fibres, which have been reported to reduce total cholesterol; however there seems to be insufficient evidence to confirm this theory. (19)

Beetroot – Flavour

This ingredient has no nutritional benefit as it is used as a flavour enhancer.

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 (20).

Citric acid

The main function of citric acid is the reduction of physical fatigue (21). 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 (22). By increasing citric acid it activates the TCA cycle and in turn speeds up ATP production thus replenishing energy.

Ascorbic acid

Vitamin C is known to be a powerful antioxidant (23). 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 (24), however the only proven function of vitamin C is the prevention of scurvy (25).

Vitamin E (DL-alpha tocopherol acetate 50%)

Dl-alpha tocopheryl acetate is otherwise known as vitamin E and is an antioxidant (26). This means that it protects the muscles from free radicals, which causes muscle soreness and damage to the muscle tissue and fat cells (27). Dl-alpha tocopheryl acetate can counteract these free radicals before damaging these parts of the body which can allow exercise to be prolonged (28).

Niacin (nicotinamide)

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 (29) as well as a reduction in fasting triglycerides (30). An increase in fasting insulin has been found due to a decrease in insulin sensitivity (31). Further research is needed for this supplement in order to understand the mechanisms.

Calcium D-pantothenate

Calcium D-pantothenate (pantothenic acid) is otherwise known as vitamin B5 and is water soluble. This ingredient helps keep a healthy digestive tract (32) and uses vitamin B2 (33). Pantothenic acid has pantethine which has been found to lower cholesterol (34).

Vitamin B6 (pyridoxine hydrochloride)

The active form of vitamin B6 is known as P-L-P (35), which is stimulated by exercise (36). 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 (37).

Vitamin B1 (thiamine mononitrate)

Thiamine is also known as vitamin B1 (38) is an essential role in carbohydrate metabolism and oxidation (39). The reported effect that have been found includes, a decrease in heart rate, blood glucose and lactate concentrations (40).

Vitamin B2 (riboflavin)

Riboflavin is a nutrient that has been found to help in fat metabolism via the electron-transport chain (41) and an antioxidant (42). 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 (43).

Vitamin B12 (cyanocobalamin 0.1%)

Research studies on vitamin B12 have found that it is required for red blood cell production (44), Protein synthesis and the repair and maintenance of tissue cells. (45).

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 (46). It can also help regulate nitric oxide levels in the blood (47).

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 (48) as well as providing energy during exercise (49).

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 an artificial 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.

The vast amounts of ingredients within this product can enable fat metabolism and give firmer muscles, in addition to this it also has antioxidant properties. This product is recommended to be taken post-workout and in the evenings. 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

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