Dean Karnazes’ Shoelaces

Origin
Dean Karnazes is an American ultramarathon runner who has run various endurance events across the world, including 50 marathons in 50 states in 50 consecutive days. Tests have shown that he is able to reduce the amount of lactic acid that builds up in the body, which causes fatigue and exhaustion. Several runners have criticized him for being more of a good headliner rather than a good runner.

Effects
They make lactic acid that normally builds up in the muscles dissipate over time and maintain a constant level. This will allows the user to perform feats of endurance without strain or risk of fatigue. However, some bystanders will not react positively to this and decide these acts are not of training but tricks.