I want to try 20 Second Fitness risk free for 90 days!

About Spencer Larson


Spencer Larson is the spokesperson and creator of 20 Second Fitness which is the result of years of personal struggle to keep the weight off and stay fit and athletic.


Spencer tried to stay ahead of his family’s history of slow metabolisms and weight gain by constantly working out or competing in organized sports. Marriage and a family slowed his life down a bit and the weight roller coaster began. His desire to race triathlons and compete was dwindling as he realized he might not be able to lose the 20 to 30 pounds he needed to race competitively. He was starting to believe the “bad genes” and “age” excuses.


A conversation with Dr. Charles Mok led him to see the value in maximum effort interval training. Spencer took these philosophies and created 20 Second Fitness.


About Dr. Charles Mok


Dr. Mok is a triple board certified physician and the owner of one of the busiest medical spas in America. He sees thousands of patients each year who are struggling to lose weight. The number one excuse he hears from his patients about exercise is, “I don’t have time for an hour a day.” To overcome this excuse, he and Spencer developed 20 Second Fitness to be as quick and efficient as possible.


At 47, he is one of the fittest doctors in America.