It is a common misconception that only bodybuilders need protein shakes/ supplements because protein shakes are only good for building mass and muscle bulk. In fact, this couldn’t be farther from the truth, dietary protein is needed by everybody and so it is crucial that we get adequate amounts to meet requirements. Bodybuilders often turn to a protein shake to help them meet their elevated protein requirements, whilst endurance athletes all too often neglect the muscle rehab and replenishment phase of training. Maybe this is through fear of gaining too much bulk, or because they place more emphasis on replenishing carbs. Whatever the reason may be, its miss placed. ENDURANCE ATHLETES MUST REPLENISH PROTEIN!
A low carb, low calorie protein that delivers at least 70% whey protein per 100g is ideal, and will not increase overall bulk unless you resistance train by lifting heavy weights etc. Instead, the protein will serve to fix the micro tears in your skeletal muscle caused by the heavy impact nature of running, and to a lesser extent, cycling or swimming.