I played rugby regularly for 13 years. Still play occasionally. I think creatine helps some with lifting in line outs, driving in the pack/scrum downs, sprinting (fast twitch muscle activity).
But wont help if its just a one time use before a match. It would be best to use it leading up to the match during regular lifting and training sessions.
Id often cycle on it during the season and off during the off season.

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