Zeinab  Al-`Alawani, Instructor of Fiqh and Islamic Studies, Graduate School of Islamic and Social Sciences, states the following: “According to ihram dress requirement, pilgrims should take off their sandals when entering the mosque and while performing tawaf and sa`i between safa and marwa. In the other manasik (rituals) such as throwing the pebbles, it is not permissible to wear such any shoes that cover the heels. So if the tennis shoes do not cover the heels, it is OK; what matters is that the shoes meet the requirement, and not the design of the shoes.”