He is a sportsman – can he take hormones at suhoor time?
Question

I play sports and I take an injection into a vein after breaking my fast, but the problem is that it is a hormone injection that circulates in the blood during the time of the fast. Does that affect my fast?.
Praise be to Allah.We hope that you are playing this sport according to the conditions set out in sharee’ah, because these games are based on showing the ‘awrah in front of spectators, let alone taking harmful things to strengthen the body as they claim. 
Vitamins and hormones, and food and drink in general, should be consumed during the night. If the effects last all day whilst fasting, that is something that is permissible. What is forbidden is to do that during the day from dawn until sunset. Allah says (interpretation of the meaning): 
“and eat and drink until the white thread (light) of dawn appears to you distinct from the black thread (darkness of night), then complete your Sawm (fast) till the nightfall” [Al-Baqarah 2:187]
Islam encourages us to eat sahoor, which is to be delayed until the end of the night, because that helps the fasting person to fast. 
It was narrated that Anas ibn Malik (may Allah have mercy on him) said: The Prophet (peace and blessings of Allah be upon him) said: “Eat sahoor for in sahoor there is blessing.” Narrated by al-Bukhari, 1823; Muslim, 1095. 
Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) was asked: 
What is meant by the blessings of sahoor that is mentioned in the hadith? 
He replied: 
What is meant by the blessing of sahoor is spiritual blessing and physical blessing. The spiritual blessing includes following the command and example of the Messenger (peace and blessings of Allah be upon him). The physical blessing includes nourishing the body and strengthening it for the fast. 
Majmoo’ Fatawa al-Shaykh Ibn ‘Uthyameen, 19 Shawwal, no. 339. 
For more information please see this answer . 
It remains for us to mention another matter that has to do with the hormones that are taken for these sports, which is to enquire whether any harm is caused by them. If it is proven that they are harmful, then it is not permissible to take them. 
It was narrated from ‘Ubaadah ibn al-Saamit that the Messenger of Allah (peace and blessings of Allah be upon him) ruled that there should be neither harming nor reciprocating harm. Narrated by Ibn Maajah, 2340. 
Al-Nawawi said: It is a hasan hadith with several isnaads that strengthen one another.
 It was classed as saheeh by Shaykh al-Albani in Irwa’ al-Ghaleel, 896. 
And Allah knows best.