Low-molecular peptides of collagen origin are of crucial importance for the body metabolism. This work aims to substantiate the use of the hydrolysates of collagen-containing fish raw materials (scale) for protein sports nutrition. Sublimated low-molecular weight peptide water-soluble and dried water-insoluble protein-mineral supplements from the sardine scale were obtained by enzymatic thermal hydrolysis. The biopotential of scale and auxiliary food additives (apple pomace, flaxseed cake, pine nuts) was investigated using standard methods. The protein content and amino acid composition of the peptide supplement and the mineral composition of the protein-mineral supplement were analysed; their high biopotential according to the above criteria was shown. The peptide supplement contains all essential amino acids having a biological value of 59.9%. The protein-mineral supplement contains no tryptophan but a high amount of calcium (22.2 g/100 g) and phosphorus (12.0 g/100 g). The high content of functional food ingredients (protein, pectin, cellulose, polyphenols, minerals, vitamin C) in auxiliary vegetable raw materials was shown. The shape of a sports nutrition product (chocolate glazed protein bar) was substantiated. The basic recipe of a 60 g protein bar having the required protein content, a given structure and high consumer properties was established. Having a protein content of 23.5%, the bar provides a 24.1% calorific value, which corresponds to the "protein-rich food" for sports nutrition according to GOST 34006-2016. The biological protein value in the bar increased relative to the peptide supplement by 12% and amounted to 71.38%. The developed protein sports nutrition bar is dietary balanced by the content of amino acids (isoleucine, leucine, valine, methionine and cystine, phenylalanine and tyrosine, tryptophan, lysine, threonine, alanine, arginine, histidine, glycine, carnosine, taurine, ornithine, citrulline), fibre, polyphenols, calcium and phosphorus and is recommended for athletes and people having an active lifestyle.