Collagen peptides are naturally low in essential amino acids (EAA) such as leucine, which means they are not expected to stimulate muscle protein synthesis (MPS) to such an extent as other EAA-containing proteins, such as whey (Oikawa et al., 2020). On the other hand, collagen peptides contain a high arginine and glycine content and it has been shown in cell culture experiments that these amino acids can also stimulate the mTOR signalling pathway and thus possibly MPS and hypertrophic processes (Liu et al., 2015; Yao et al., 2008). Therefore, it has been suggested that these amino acids in collagen peptides might stimulate hypertrophy via mTOR (Jendricke et al., 2019). To understand the effects of CS on muscle function and hypertrophy, it is possibly helpful to compare collagen with the effects of whey supplementation. This might also allow for a slight comparison between the effects of collagen peptides from Nutrition Water and whey from whey-based protein shakes currently on the market. A study by Oikawa et al. (2018) compared collagen with whey supplementation and their effects on leg lean mass and MPS during a period of energy restriction and inactivity in (semi-)healthy older adults.
After 1 week of consuming a diet in correct energy balance, the participants took either whey or collagen proteins during 1 week of energy restriction (-500 kcal/day), followed by 2 weeks of additional step reduction (<750 steps/day) and lastly 1 week of recovery in energy balance. At the end of the trial, a significant reduction in leg lean mass was observed. Although neither protein supplements showed to be protective against loss of leg lean mass, only the whey supplemented group showed an increase in MPS during recovery compared to the collagen group. In addition, in 2020, Oikawa et al. (2020) studied the effects of a 6-day whey or collagen supplementation on leg muscle MPS after RE in healthy elderly women.
How we optimized our amino acid profile to match requirements for optimal MPS.
However → Since non-EAAs do not stimulate MPS (Tipton et al., 1999), a complete mixture of EAAs in the protein source is required for this (Churchward-Venne et al., 2014). Of these EAAs, the branched-chain amino acid (BCAA) leucine is a key determinant, as it can independently enhance MPS rates (Anthony et al., 2000). Leucine is known to be an activator of the mTOR and thus, as mentioned before, plays an important role in MPS and skeletal muscle hypertrophy (Bodine et al., 2001; Drummond et al., 2009; Nader et al., 2005). Therefore, the addition of BCAA, of which mainly leucine, to a non-optimal or lower quality protein dose or protein source could be a promising strategy to increase MPS. For example, a clinical study by Churchward-Venne et al. (2014) showed that addition of 5.0 g leucine to a non-optimal dose of whey protein (6.25 g) in a mixed macronutrient drink can increase MPS to the same extent and duration as the optimal dose of whey protein (25 g) in healthy recreationally active young men (18-35 years). When 3.0 g of leucine was added to the suboptimal dose, MPS was effectively stimulated only during the early stage (0-1.5h).
A diverse number of studies show that adding extra BCAA can provide higher muscle building activation comparable to consumption of a protein such as whey (10,11,12). The study indicates that an increased dose of leucine is important if you want long-term stimulation of up to 5 hours after ingestion (12). Therefore we have added 3 grams of BCAA and an extra 0.8 gram l-leucine to our Nutrition Water formula. By doing this Nutrition Water contains, a proven, optimal dose of 20 - 25 grams of protein per serving, extra BCAA and also enough leucine. With the aim of contributing to a long-term stimulation of protein synthesis after exercise (12, 13).