Decathlete

Hop scotch race:
Sweep the D-pad in counter-clockwise Full-Circle starting at Up, then press X as the course number is announced in the 100 meter event.

Rolling race:
Sweep the D-pad in clockwise Full-Circle starting at Up, then press X as the course number is announced in the 100 meter event.

Alternate high jumps:
Select the height of the bar, then press Left or Right before beginning your attempt.
This allows selection of three different jump styles and camera views.

Alternate shot put view:
Press Left or Right after your throw.

Alternate shot put throw:
Sweep the D-pad in a Full-Circle when the power meter reaches the far left.
You character will spin as in the discus throw.
Release the ball after the spin.

Control the blimp:
Press R on controller two to control the blimp's circular motion when it appears.

Extra player:
Get over 8000 points in arcade mode.
Hold X over a mode option in the main menu.