Professional athletes are typically risk takers by nature. They would not be in the positions that they are in life if they were not. You have to be some sort of risk taker to believe that you can overcome the long odds against you and make it as a professional athlete. Taking risks has its place in your financial life but only after you have structured your portfolio with guaranteed investments.
Individuals whose incomes are in the highest brackets should look to guaranteed investments with low tax consequences. There is no use paying all of your money to Uncle Sam. Municipal bonds are good low risk safe investments for athletes. Municipal bonds can have higher yields than many corporate bonds because they are free from state income taxes. They also are typically guaranteed by the state or local government. As long as you don't live in a bankrupt city, your investment should be fine.
One of the ways that you can make more money investing is by risking less of it.