Tim S. Grover is an American author, entrepreneur, and motivational speaker. He is best known for his books "Relentless: From Good to Great to Unstoppable" and "Jump Attack: The Formula for Explosive Athletic Performance". He is the founder of Attack Athletics, a performance training facility in Chicago, and the CEO of TMG, a sports performance and leadership training company. Grover is a sought-after speaker and consultant, having worked with some of the world's top athletes, including Michael Jordan, Kobe Bryant, Dwayne Wade, and many others.