# Sports and birth date **URL:** \ **Category:** Factual Questions\ **Created:** [October 16, 2024, 10:05am UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859 "2024-10-16T10:05:44Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Danger\_Man](https://avatars.discourse-cdn.com/v4/letter/d/6de8d8/32.png) [@Danger\_Man](https://boards.straightdope.com/u/Danger_Man)\ **Post date:** [October 16, 2024, 10:05am UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/1 "2024-10-16T10:05:44Z")
I have read articles about how being born early in the year is an advantage when it comes to sport. The theory is that you gain an early advantage that compounds as you get older. > **[How to build a champion: Be born at the right time](https://www.bbc.co.uk/sport/olympics/18891749.amp)** > > The Open University find some unusual factors that make an Olympic champion. But then I read another article about how in Sweden, as soccer players get older, the ones born later in the year are overrepresented. It cites something called the underdog-theory, says that the ones born later have to work harder and ones they get older they have more skills. Of the ones with the most national matches for Sweden, 9 out of 10 are born in the second half of the year. (News article in Norwegian) > **[Svensk varsko til norsk idrett: – Ikke gjør som oss](https://www.vg.no/sport/i/AvGXV3/svensk-varsko-til-norsk-idrett-ikke-gjoer-som-oss)** > > En ny bok advarer mot svenske tilstander i norsk idrett. Det er dårlig nytt. So which one is correct? Are there other factors at play here? ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [October 16, 2024, 12:31pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/2 "2024-10-16T12:31:24Z")
This was IIRC part of the Freakonomics study. In assorted sports (Hockey was a good example) where players start young and the development is intense for the best because of the money involved in pro sports, the child of 6 in a particluar sports category enojys a massive advantage in terms of size, cognotive development, previous unorganized practive, if they are 6yrs 11mo versus barely 6 years. Then the better players get the attention and experience. The younger ones in the category nevr catch up. In the example cited, the National Hockey League, the cut-off for hockey tiers tended to be a birthday of Jan 1st or later and the majority of players were born January to March. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [October 16, 2024, 12:43pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/3 "2024-10-16T12:43:18Z")
But there are other cutoff dates that may influence other sports. The first article cited in the OP discusses Sept 1 as a cutoff date for the school year, so sports where the early development happens in schools have more participants from the last four months of the year. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 16, 2024, 12:47pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/4 "2024-10-16T12:47:28Z")
Said another way, one of the confounders is going to be what are the within-year cutoff(s) to form age group(s) for the particular youth sport league(s) of the sport(s) you’re studying in the particular country(ies) you’re studying in the year(s) when the athlete(s) you’re studying were of the age(s) to be affected by those cutoff(s)? For the people who eventually become pro’s it’s not as simple as cutoffs for grade school. Not even wholly within the USA where “grade school” itself is at least a mostly-uniform concept. I think the front-of-year vs. back-of-year rubric can probably be used to predict high school football stars vs duds. As a naturally small man who came from being a naturally small boy and oh by the way one of the youngest in his grade, that was sure the way to bet with me. Lotta kids with even remotely pro potential have a lot more than their grade position and intramural school sports to dfrive their prep.rots ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 16, 2024, 12:50pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/5 "2024-10-16T12:50:28Z")
Here are three older threads on what amounts to the same conversation: whether & how much advantage there is to being relatively older or younger within your school class at various ages: 2013: > [@Redshirting Kids for Kindergarten](https://boards.straightdope.com/t/redshirting-kids-for-kindergarten/670392): > > Hi fellow Dopers. So I came across this article: [http://www.nytimes.com/2007/06/03/magazine/03kindergarten-t.html?pagewanted=all&\_r=1&](http://www.nytimes.com/2007/06/03/magazine/03kindergarten-t.html?pagewanted=all&_r=1&) That seems to advocate holding kids back a year before they start kindergarten. My son is almost 2.5 years old. He will be three right smack in the middle of April. In Illinois, you need to be five before you can start kindergarten so little Lochdale would be 5 plus a few months when he would be eligible to start kindergarten. If we were to wait a year the… 2015: > [@Thoughts on Redshirting - Kindergarten](https://boards.straightdope.com/t/thoughts-on-redshirting-kindergarten/728885): > > So this has been asked before, that is, the pros and cons of Red Shirting a child so that they start Kindergarten a year later then they otherwise could start. Seeing how kids are starting school again I thought I would ask again for Dopers opinions and experiences with Red Shirting. By way of background, my son is 4 (born late April, 2011). He is fairly speech delayed and has been in speech therapy now for two years. So he is going into five day pre-K in two weeks. My thoughts are that we … 2016 ref the high school-to-college transition: > [@Why redshirt when taking a gap year more practical?](https://boards.straightdope.com/t/why-redshirt-when-taking-a-gap-year-more-practical/743632): > > So I’ve noticed that a lot of parents said there sole reason for redshirting their fall child was that they didn’t want them to go to college at 17. But if that’s the only reason, why not have them take a gap year instead? I understand there are other reasons for redshirting, but to do it solely because you don’t want your kid starting college at 17 is just silly. It’s 13 years away. And besides, how do you even know they’ll want to go college? Most people don’t these days. You should make a dec… ---
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [October 16, 2024, 1:02pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/6 "2024-10-16T13:02:34Z")
> [@md-2000](#): > > In the example cited, the National Hockey League, the cut-off for hockey tiers tended to be a birthday of Jan 1st or later and the majority of players were born January to March. Not arguing against the empirical findings there, per se (which I am familiar with), but often future pro hockey superstars are so good that they even dominate against kids significantly older than they are, often much older, and end up playing in older leagues than what their birthday/year would indicate. You’d think that would wash out the calender/monthly effect cited; maybe when very young some get discouraged before they can learn all the basic skills. I am checking the top all-time NHL leaders in adjusted points, and Mario Lemieux is the only guy born in Oct/Nov/Dec (Oct 5), but I believe he was a big kid from an early age. Patrick Kane, 1st Nov. baby (19th); Alex Delvecchio, Dec 4th (he’s still alive @ age 91 note); Ray Bourque, Dec 28. I found a few more December guys, but the Oct/Nov ones, thru #50, remain just Mario and Kane. ---
**Author:** ![Jas09](https://avatars.discourse-cdn.com/v4/letter/j/d07c76/32.png) [@Jas09](https://boards.straightdope.com/u/Jas09)\ **Post date:** [October 16, 2024, 1:05pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/7 "2024-10-16T13:05:52Z")
> [@Danger\_Man](#): > > But then I read another article about how in Sweden, as soccer players get older, the ones born later in the year are overrepresented. This doesn’t seem to match the research a quick Google search shows. Unfortunately I can’t read the Norwegian article. Here is a study showing the Swedish National team players, at least around 2000, were strongly biased towards being born in the first quarter of the year, and that this effect extends all the way back to the youth systems. [https://www.idrottsforum.org/articles/peterson/peterson040831\_eng.pdf](https://www.idrottsforum.org/articles/peterson/peterson040831_eng.pdf) (PDF) This presentation from US Soccer shows that the relative age effect applies pretty universally in soccer: [https://www.usyouthsoccer.org/wp-content/uploads/sites/160/2023/09/Relative-Age-Effect-in-Elite-Youth-Soccer.pdf](https://www.usyouthsoccer.org/wp-content/uploads/sites/160/2023/09/Relative-Age-Effect-in-Elite-Youth-Soccer.pdf) (PDF) ---
**Author:** ![Jas09](https://avatars.discourse-cdn.com/v4/letter/j/d07c76/32.png) [@Jas09](https://boards.straightdope.com/u/Jas09)\ **Post date:** [October 16, 2024, 1:13pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/8 "2024-10-16T13:13:23Z")
> [@dtilque](#): > > But there are other cutoff dates that may influence other sports. Yes, this is critical. In the US, at least, soccer and hockey seem to work entirely on birth year. So if you are born in Dec 2014, the “youngest” group you can participate in is typically labeled 2014B or 2014G. You can always play with older kids, but never younger. So a December-born boy or girl will always be playing with many kids that are almost an entire year older than them, or are so talented that they are playing “up a year”. Baseball is different. Little League uses August 1, I think. But my local league uses May 1. I’ve seen other variations as well. So it’s possible that being born late in the year is better for baseball. The biggest long-term effect with RAE is that once a kid is identified as “talented” at 10-13 years old they get more and more training, which only increases the skill gap. And often that “talented” identification is actually just more advanced physical development due to being older than his/her peers. ---
**Author:** ![Danger\_Man](https://avatars.discourse-cdn.com/v4/letter/d/6de8d8/32.png) [@Danger\_Man](https://boards.straightdope.com/u/Danger_Man)\ **Post date:** [October 16, 2024, 1:50pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/9 "2024-10-16T13:50:05Z")
Reading the Wikipedia article ([Relative age effect - Wikipedia](https://en.m.wikipedia.org/wiki/Relative_age_effect)), I did see the underdog effect mentioned, and this study: [Examining relative age effects on performance achievement and participation rates in Masters athletes - PubMed](https://pubmed.ncbi.nlm.nih.gov/17786690/) ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [October 16, 2024, 2:45pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/10 "2024-10-16T14:45:26Z")
The sport I’m most familiar with, tennis, is year-round, at least in SoCal. Age eligibility is determined on a per-month basis. In the entire month of your birthday, you are considered to be your new age. So, if you turn 15 on Halloween, you are 15 the entire month of October for purposes of playing rated tennis. If tournament or league play crosses multiple months, eligibility is determined at the beginning of play, not the end. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [October 16, 2024, 7:28pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/11 "2024-10-16T19:28:08Z")
This is a known issue in early education with Leo Children as they were traditionally the youngest in class and the difference between a 6y0m child vs a 6y11m child is huge in learning. Side note: when I taught AP Statistics I found a professional study that the students could understand and used it to teach then how to read/write statistics in research. I was observed by the principal who thought the lesson was phenomenal and a good understanding of what the students needed since all of them were headed for college. I mean it was the best observation I have ever had as a teacher. But then the principal with an ink-still-wet Ph.D. pointed out that he was a Leo child and he had a doctorate and during the lesson I did not point out explicitly that Leo children can be successful and so he fired me. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 16, 2024, 10:10pm UTC](https://boards.straightdope.com/t/sports-and-birth-date/1008859/12 "2024-10-16T22:10:14Z")
Screw those old Leo kids. What about us Virgo children who were/are younger yet? Not every state uses the same cut off.