The 100m Dash (or simply 100m, also known as the 100m Sprint in Mario & Sonic at the London 2012 Olympic Games) is an Athletics event in both the Wii and Nintendo DS versions of the game Mario & Sonic at the Olympic Games, and both the Wii and Nintendo 3DS versions of Mario & Sonic at the London 2012 Olympic Games. It is one of the first events of the game, and can be found in the "Track" section of the "Athletics" category. The goal of the event is to reach the finish line first. The longer version of this event is 400m, and the 110m Hurdles event acts very similarly to 100m. The 100m Freestyle has very similar controls to 100m. This event mainly requires speed.
 Wii Version
This event can be played with either the Wii Remote and Nunchuk together, or the Wii Remote by itself. When READY appears, the player needs to hold the Button down to build up energy. If the button is released and the Wii Remote is flicked down at the same time when GO appears, the player will get a speed boost called a Start Dash. This boost is crucial in winning the game. However, doing it too early will result in a foul, causing the event to start over. After leaving the starting line, the player has to alternately shake the Wii Remote and Wii Nunchuk fast to run. Speed is gained the faster the two controllers are shaken. If the speed meter gets into the red, the player will start to run extra fast, with a small blue veil trailing behind them. The track is relatively short, however, so the race does not last too long. The controls when only using the Wii Remote are the exact same as with the Nunchuk, but the player has to shake the Wii Remote by itself, instead of the Remote and Nunchuk together. The first player across the finish line wins!
 DS Version
The features of the event are very similar to the Wii version. Pressing down on the touch screen with the Stylus during the start of the event builds up the characters starting energy. Running is controlled by swiping the stylus left and right across the touch screen. The faster the swiping the fast the character runs. Near the end of the course, an "!" will appear above the controlled racer signaling the player to swipe the stylus upwards. This action makes the characters take a short leap shaving off a few milliseconds off their time.
 Wii Version
Mario's sixth event in the Wii version of Mario & Sonic at the Olympic Games is 100m Dash. To win it Mario must simply finish before his rival does. In other words Mario must cross the finish line before his rival crosses it. His rival is SEGA's Sonic the Hedgehog.
Amy Rose's third event in the Wii version is 100m Dash. It is simply a regular race with a twist at the start. This mission is similar to the event in that she must come in first to win but the difference from the event, the twist, is that she must begin the race with a perfect start. Basically, the player must hold be and let go at exactly the right moment for her to zoom forwards at the beginning of the race.
Sonic the Hedgehog's sixth event is in the Wii version is also 100m Dash. It is practically the same as Amy's third event. To win, sonic must complete the race in first and get a perfect start. The only difference is that here, he must start on exactly the same moment as "GO" appears to cross the finish line before his opponents; otherwise, he will lose.
Shadow the Hedgehog's sixth event in the Wii version is 100m Dash. It is exactly the same as Mario's sixth event. To win it, Shadow must simply finish before his rival does. In other words, Shadow must cross the finish line before his rival crosses it. His rival is Sonic the Hedgehog.
 DS Version
Vector the Crocodile's first event in the DS version of Mario & Sonic at the Olympic Games is 100m dash. To win it Vector must finish the race within fifty seconds, if it takes him longer he will fail. Another difference is that instead of crossing the finish line first, he must cross the finish line in second place, right after the first place person in under fifty seconds.
Blaze the Cat's fourth event in the DS version is 100m dash. To win it she must not cross the finish line first, second, third, fourth or in any specified position at all! All she must do is finish within .5 seconds of her rival, that means .5 seconds before or .5 seconds after. Her rival is Princess Peach so she must keep Peach in her sights at all times and finish extremely close to her.
Sonic the Hedgehog's first mission in the DS version is 100m dash. It involves him coming in first, the only difference being how he starts. He must start the race by using a good start. The start must be at the same moment or a few milliseconds after the judge calls "GO". If it is not during that time limit or if Sonic does not win the race, he will not complete the mission.
Shadow the Hedgehog's first event in the DS version is 100m dash. The rule of this event is not to come in any specified place but instead to simply keep ahead of another player.
Wario's first mission in the DS version is 100m dash. The mission is a regular race and, just like in Vector's race, he must not cross the finish line first, he must cross it second. The only hitch other than coming in second and not first is that he must finish the race with a lunge which means the player must slide the stylus to the side of the screen when the exclamation mark ("!") appears above his head.
Mario's sixth, final and hardest mission in the DS version is to beat the master of speed, the chaos emerald-using, crime-fighting, speedy, blue hedgehog; SEGA's mascot, Sonic the Hedgehog! Mario must race Sonic to the finish line and cross the finish line before Sonic does. To do this Mario will have to get almost perfect because Sonic is in top condition which means he will run much faster than usual.
Wii Version: Kick off from the starting block and sprint along the 100-meter stretch to the finish line in as short a time as possible to win. Make sure you wait for the starting signal, as kicking off too early will result in a false start.
DS Version: Take an early lead with a start dash at the beginning of the race, then slide the stylus left and right to sprint all the way across the finish line