While most of us experience a blood blister sometime in our life, it’s worth explaining the sports medicine behind them. Blood Blisters and regular blisters occur when friction tears the top layers of skin, leaving a bubble between the healing layers of skins. While there is not much you can do to remedy an already formed blister (sorry!), you can take preventative measures by ensuring your footwear is properly fitted and that you always wear a good pair of socks. If a blister does appear, you will want to take precautions to make sure it heals properly. Applying a Band-Aid or gel can help reduce further friction.