10 differences between indoor and outdoor athletics tracks

From the width of the lanes to events hosted on them, indoor and outdoor athletics tracks have specific factors make the difference in a competition.

At the end of an intense season of indoor athletics, athletes prepare for the outdoor events. Here are the key differences between indoor and outdoor athletics tracks:

• Weather conditions don’t affect indoor events, where competitions are held under controlled conditions, eliminating the uncertainty of the weather.
• Indoor tracks are 200 meters long, while outdoor tracks are 400 meters long, so during indoor meets, the athletes run the same distance with twice as many curves.
• Indoor and outdoor events do not include the same activities. Races are hosted in both settings (although some of the races are different lengths). But throwing events cannot take place indoors for safety reasons, because there’s not enough room for the javelin, discus and hammer events.
• The width of the lanes is also different: Indoor lanes range from 0.90 to 1.10 meters wide. (At the Birmingham Arena, where the most recent IAAF World Championships was held, the width is 0.95 meters). Outdoor lanes are 1.22 meters wide.
• All outdoor tracks have an aluminum curb positioned above the internal white line of the first lane. The development of 400 m is calculated at 30 cm beyond the aluminum curb. Curbing is currently not required for indoor tracks, although it is recommended in the IAAF’s regulations. (Indoor tracks with curbing are generally more recent.) Therefore, on some indoor tracks, the internal perimeter is 30 centimeters and on others it’s 20 centimeters, because until recently, none were equipped with curbing.
• On outdoor tracks, athletes run on a flat surface, whereas on indoor tracks, not only is the radius of the curves much smaller, but there’s also a slight incline.
• To aid the runners, curves on indoor tracks are often (but not always) clothoidal (meaning that they have different radiuses, normally three). All tracks for high-level competitions have clothoidal curves. Outdoor tracks generally have curves with only a single radius, although some with multiple radiuses do exist.
• Many athletes train on outdoor tracks, simply because they are more common. Those who specialize in indoor disciplines try to train on indoor tracks, but such tracks are relatively rare in Europe.
• For indoor races over 400 meters, the athlete must also train and prepare a strategy for the lane change, which occurs during the second lap when all the athletes converge on the innermost lanes. (For the 400 meters on outdoor tracks, each athlete remains in his or her own lane throughout the race.)