To get a glow on a shaved body, or preferably...natural coat...I feed ground flax, kelp, beet pulp, good quality feed and hay. Nothing will put a real true shine on the bod like good food, and conditioning.
As for the enhancers, there are dozens upon dozens on the market, and I have tried most...but cannot do without simple mineral oil and show sheen. I use mineral oil on the hooves, mane, tail, and face...as well as carrying a lightly oil-spritzed rag to run over the horses shoulder, hip and gaskin as I enter the ring.