He said inclusion of a clause that prohibits athletes from competing in races 60 days before or after an appearance in a John Hancock event was intended to insure top performances.

The rules prohibit athletes from entering into agreements with agents before their college eligibility expires and the taking of such money.

Many states in the South had laws prohibiting black athletes from competing alongside whites.

The league prohibits athletes from becoming eligible for the N.F.L. draft until they have been out of high school for at least three years.

In order to prevent SIS, guidelines have been established to prohibit athletes from returning to a game prematurely.

In Connecticut, the high school sports governing board prohibits athletes from playing on traveling club teams in the same season they play the sport in high school.

Jake Featherston attempted to prohibit athletes from Haiti and Liberia from participating, but was overruled by the International Olympic Committee.

Because of South Africa's policy of apartheid, the I.A.A.F., which expelled South Africa in 1976, prohibits athletes who compete there from competing anywhere else.

Hmm," (July 26): It would be unfair to prohibit athletes from simulating a natural environment other than where they live, thus denying them physiological benefits available to other athletes.

NCAA rules prohibit athletes from allowing their name or image to be used to promote an off-campus business or for-profit entity.