translation:
Father in heaven, I am doing this for you..
With great difficulty  am giving up on my dream and I am canceling my participation in the competition in Spain.
The reason is that the competition was mean to be held on Shabbos which connects to Shvuos on Motzei Shabbos. That is where something started to arouse in me, as someone Shomer Shabbat, I already felt my conscience about competing on Shabbos and Shvuos which is the time of the giving of the Torah, despite the fact that I had planned on competing on Shabbos, I began to find all sorts of reasons, I planned to stay in a hotel near the competition so I would not need to travel in a car to get there on Shabbos, and I would not actually desecrate the Shabbos in any way with my actions, even though competing on Shabbos is a desecration,  but the honor and glory of the competition blinded me...
But what stopped me is the Shvuos holiday. I will not stand on the stage in briefs at the time of the giving of the Torah, when the Jewish people received the Torah.
Thank you, Father in Heaven for opening my eyes.
I know that my reward in heaven is definitely humongous for giving up something I wanted so much after so many years of hard work..

This was written by Israeli bodybuilder Mordy Harosh from Jerusalem. Relevant background is that Harosh used to be Haredi, but is no longer - I saw descriptions of him as no longer being frum but in his post he says he is generally shomer shabbos.