Exercising Before Shacharit (Morning Prayers)
I have a busy morning schedule and get up very early to exercise. Is there a problem with doing this before morning prayers?
The Aish Rabbi Replies
If you have a choice, it’s not the ideal. Preferably, morning prayers should be almost the first thing we do in the morning. The Talmud (Brachot 10b) strongly criticizes people who eat before morning prayers (based on I Kings 14:9, understood figuratively by the Sages to be saying “You have cast Me behind your arrogance” – you first care for yourselves and only then turn to Me.) (Water is fine, as well as coffee or tea for people who need it to wake up.) Likewise, we may not deal with work-related matters or any involved matter before praying. God must come first.
However, if exercise is a health-related need for you and there is no other time you can realistically do it, then it would be alright. Since it is a health need, it is not a form of honoring yourself over God, but ensuring your body is fit to serve its Creator. (In fact, the same is true of eating for someone who is too weak to wait until after Shacharit. See this past response regarding eating on Shabbat morning.)
Note that often in the winter dawn is quite late. If you begin exercising more than 30 minutes before dawn, then it is fine (according to all) to begin, and to continue until dawn.
(Sources: Talmud Brachot 10b, 14a, Shulchan Aruch O.C. 89:3-5, Mishna Berurah 17, Laws of Daily Living, Vol I (ArtScroll), p. 158 with footnote 48.)