Javelin equipment

The Javelin
The size, shape, minimum weight, and center of gravity of the javelin implement itself are all defined by IAAF rules. In international competition, men throw a javelin between 2.6 and 2.7 meters in length and (at least) 800 grams in weight, and women throw a javelin between 2.2 and 2.3 meters in length and (at least) 600 grams in weight. The javelin is equipped with a grip, approximately 150 mm wide, made of cord and located at the javelin's center of gravity (0.9 to 1.06 meters or 0.8 to 0.92 meters from the tip of the javelin for men's and women's implements, respectively).
Javelin shoes have to be strong and supple in the sole, subject to the strain of spinning, with robust, semi-rounded edges for easy turning and greater spin speed. Although lightweight, they have to bear the weight of extra-large sized athletes, hence the strings are often supported by extra strapping (velcro or similar).