I think that more sports should consider having a shirtless uniform, or at least making it optional. In writing this, I'm really hoping to reach some of the promoters and organizers and encourage them to think about whether their sport really needs a shirt or jersey as a requisite uniform component. Whether it's a national or international organization, or just a small local league, it's worth considering a less restrictive uniform requirement.
Now some sports governance bodies have some truly assinine uniform regulations, and I think if you are busy
regulating the stitching on participants' undergarments you need to stop and think about what purpose the uniform really
practically serves for your sport.
That said, running is actually a prime candidate for a shirtless uniform. It's already wide-spread practice to train shirtless.
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Many other sports are also commonly practiced shirtless. Any sport that is commonly practiced shirtless should consider an official uniform that doesn't require a shirt or jersey. Team colors and even player numbers can be displayed on shorts.
For instance, basketball:
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baseball:
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soccer:
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And even tennis, although it has traditionally been rather stuffy about uniform in formal tournaments:
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While some sports, like football, call for upper-body protective gear, why not forgo the shirts when playing two-hand touch or flag football?
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Gymnastics is another excellent example of a sport commonly practiced shirtless.
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It's also noteworthy that it is not uncommon in sports that require a shirt or jersey as part of the standard uniform to see players on the sidelines without them. Why should this be accepted, but not for them to play without them on the field?
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So, if you are involved in organizing a sports league or event, or writing the regulations for a sports governance body, why not consider a shirtless uniform, or at least making the jersey optional? A little bit of freedom for the players does no one any harm.