The San Francisco 49ers offseason workout program gets going on Monday, with the arrival of some portion of the team. The program is voluntary, but numerous players have a financial incentive to be on hand for the program.
Aside from base salaries, signing bonuses, and incentives, many contract in the NFL include workout bonuses. These cover attendance at the annual offseason workout program that runs from April to June. Colin Kaepernick is the most notable this year due to the trade rumors, with a $400,000 bonus paid out if he attends 90 percent of the program. I don't know if there is a uniform attendance percentage for payment.