Trainer

The Trainers are characters in the Wii Fit series who serve as the player's trainer in Yoga and Strength Training activities. The player can choose their preference between the Female Trainer or Male Trainer, though they may occasionally fill in for each other on some sessions. In Wii Fit and Wii Fit Plus, both trainers wear different-colored clothing depending on the type of activity, matching the color of their studio (blue for Yoga, green for Strength Training, and yellow for either when accessed through My Wii Fit Plus). In Wii Fit U, the designs of the Trainers have been updated along with the overall presentation of their activities, having more detailed faces and always wearing green.

Personality
Though the two trainers share largely the same writing, and there is little necessity for them to have defined personalities, it is clear that they have a passion for the work they do, and are very supportive of the player in their pursuit of fitness. Although they mostly maintain a calm disposition, they are shown to have a friendly competitive side as well, in exercises such as the Jackknife Challenge.

In the Super Smash Bros. series, the trainers are depicted in a somewhat comedic light. When showing off the Wii Fit Trainer's moveset in a video for E3 2013, Masahiro Sakurai described her as "a health nut" who uses moves that she thinks will contribute to her health. . Almost all of their animations, not just attacks, incorporate exercise, such as doing push-ups when crouching, stretching their back when standing against a ledge, and sleeping in a spinal twist position. In the opening cutscene of Adventure Mode: World of Light in Super Smash Bros. Ultimate, the Female Trainer appears aloof to the situation at hand, performing the Tree pose before being engulfed in Galeem's light.

Super Smash Bros. series
Starting with Super Smash Bros. for Nintendo 3DS and Wii U, the Trainers appear as a playable fighter under the name Wii Fit Trainer, which has since been used in other crossover appearances. Most of their attacks and other animations reference the activities they instruct in their home series, while two of their Special Moves utilize equipment used by Mii characters in Balance Games and several of their standard moves being yoga poses. Their design is largely based on how they appeared in Wii Fit Plus (with alternate colors representing those seen with Strength Training and My Wii Fit Plus), but their faces were updated in Super Smash Bros. Ultimate to appear more detailed similarly to in Wii Fit U, a change made at the request of the Wii Fit development team.

Super Mario Maker
In Super Mario Maker, the Female Trainer appears as one of many unlockable costumes to use with the Mystery Mushroom. She stands and runs while holding the Dancer pose, and her voice is heard when she jumps. She also appears as part of the Wii Balance Board's costume, standing on him in the Dancer pose for the "taunt" the costume performs when holding up on the + Control Pad.

amiibo website
''This female trainer helps you in the Wii Fit™ series, instructing you during fitness exercises. She often advises you to maintain your center-of-balance, helping you tone up and burn calories. Recently, she has also shown herself as a capable close-quarters fighter.''

Super Smash Bros. for Nintendo 3DS & Wii U trophies
Wii Fit Trainer: ''The female trainer who helps you in the Wii Fit series. She favors a fighting style composed of yoga poses. This makes her a capable close-quarters fighter, but she has ranged attacks as well. She also has a move called Deep Breathing, which can heal you and increase attack power if timed right.''

Wii Fit Trainer (Alt.): ''The male trainer from the Wii Fit series, his neutral special Sun Salutation charges up a ball of light that, when launched, will heal him a bit. His Jackknife pose is excellent for toning the abdominal muscles, but in Smash Bros. the Wii Fit Trainer uses it as an air attack. Timed right, the attack can hit twice!''

Wii Fit U Trainer: ''The Wii Fit Trainer has the most impressive balancing skills we've ever seen! Many people probably started yoga to achieve this perfection. However, these abilities aren't developed overnight; it takes lots and lots of yoga practice. We won't judge if you'd rather take it easy—we aren't exactly writing this from the gym.''

Trivia

 * The files of Wii Fit contain an unused, unfinished model for a realistically-colored Female Trainer.
 * In the Wii Fit games, the trainers can sometimes run a bit late for their sessions, appearing within a slight delay from the environment loading and saying that they think they stayed up too late the night before. This is followed by a reminder of the importance of sleep for a healthy lifestyle.