glukosamine is a component found in meat and is given to hard working horses and dogs. even people who train hard will add glukosamine. this component helps lubing the joints making them work properly. it also helps the body to rebuild bones, muscles, cartilage, tendons and leading-strings. glukosamine is recommended for working dogs and old dogs, but we do add glukosamine in our puppies food aswell to lower the risk for hd/ad. i do not know if whey proteine really is the same thing. whey proteine is rather a proteine source, but since it is vegetable-based i don't think that it is optimale. dogs are predators with a digesting system made for meat based food. dogs usually cannot digest vegetable-based protein (soya, whey, corn, etc) as good as meat based proteines. we feed certain amino acids prior and after work out for building up and maintaining muscle tissue and to avoid the body breaking down muscle tissue because of hard work out, but that is not a substitute for glukosamine.