Instructions
Choose "Wii Fit" exercises and activities that are available and play them. Each time you complete an exercise or activity, the amount of time you spend participating is added to your "Wii Fit Bank" as "Wii Fit Credits."
Continue exercising with "Wii Fit" until you accumulate 1 hour and 40 minutes of credits. After achieving this, "Rhythm Boxing" is unlocked in the aerobics section of the game. Only a three-minute routine is available at first.
By successfully completing the three-minute version of "Rhythm Boxing" three to five times, you can unlock the six-minute variation.
Continue playing either the three-minute or six-minute modes of "Rhythm Boxing" to unlock a third mode that lasts for ten minutes. The ten-minute mode requires you to successfully complete either of the unlocked versions five or six times.