Landmark study indicates Semenya has advantage

IAAF says research justifies decision to bar Olympic champ

LONDON - The governing body of world athletics on Wednesday welcomed the results of a new study showing high testosterone helps women run better, saying it justifies the decision to bar Olympic champion Caster Semenya from key races.

In a study published in the British Journal of Sports Medicine, Swedish researchers found women with higher testosterone can run longer and have more lean muscle mass.