You can absolutely use herbal powders in workout shakes. They provide a great way to add medicinal potency and micronutrients to your smoothies and shakes. Our All-natural pre- and post-workout mix is a great example of a vegan powder including a carefully chosen blend of herbs (that promote muscle recovery pre- and post-workout) that was designed to be added to protein shakes, as a natural alternative to synthetic or dairy-based powders.