What is the ruling on delaying prayer for someone who is studying or exercising, and the prayer times coincide with the beginning or middle of their classes or training sessions?

It is not permissible to delay prayer beyond its prescribed time. If you are not missing the prayer time entirely, but rather missing the virtue of praying at the beginning of the time because you leave the class half an hour after the Adhan, then there is no harm in continuing your studies. You are not obligated to leave the class as long as you will pray within its designated time. Be keen on praying in congregation at the mosque, or with some of your brothers if you do not find a mosque, for the Prophet, peace and blessings be upon him, said: "Prayer in congregation is twenty-seven times superior to prayer offered individually." If there is no harm in leaving the class, we advise you to go out and pray in the mosque at the beginning of its time. As for playing sports, it is not a necessity for which you should abandon congregational prayer at the beginning of its time. Be keen on performing the congregational prayer at the beginning of its time in the mosque whenever possible. If that is difficult, then be keen on praying in congregation with your brothers within the time. Beware of letting the prayer go beyond its time, for the sin of that is greater than the sin of adultery, theft, drinking alcohol, and taking a life, by the consensus of Muslims.