This tip requires more research to definitively argue that it will decrease injury rates in all collision sports. Regardless, it is a change that I believe would lower injury rates in the sports, especially over long seasons. Avoid more than one game per week in collision sports.
Researchers studied European professional soccer players, looking specifically for differences in injuries between players who played two matches per week compared to athletes who played in only one match per week. The soccer players who competed in two matches per week had injury rates over six times higher than the players who played one match per week. Plus knee, ankle and thigh injuries were all much more common among the two-match players.
I suspect that this trend would hold true for most collision sports – football, rugby, lacrosse, soccer and more. Multiple games in one week can take a toll on the players physically. Extended over many weeks over a long season, serious injuries could occur.
I realize the scheduling difficulties, travel and field availability that many teams and leagues have. I think adjusting schedules in any way possible to better spread out games and tournaments would decrease injuries. Making this change to prevent players from competing in more than one game per week might also allow athletes to play who might otherwise sit out with a relatively minor injury. Team performance and overall quality of competition would likely improve as well.