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NFL players: height and weight over time

noahveltman.com

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Re: NFL players: height and weight over time

#21
post #15
post #6

Craig M. Booth has done some very nice visualizations on this subject [1]. I found this chart comparing height/weight of 2013 rosters by position [2] particularly interesting and this set [3] covers a question that anyone who has read Outliers has probably wondered about. 1: http://www.craigmbooth.com/category/nfl/ 2: http://www.craigmbooth.com/height-and-weight-of-every-active... 3: http://www.sportsballweekly.com/t…

Ugh, on [3], watch out for the non-zero axes. NHL and NBA start their axes at 0, while the others do not. Very tricky, and very deceiving. I think NFL would look very similar to NBA if plotted the same way (they're both within ~10-15% of the expected value).

My guess with NBA players would be that the proportional increase in their heights would be higher.

Does anyone know changes to average weight/height for the population in the US?

Re: NFL players: height and weight over time

#22
What's interesting is before the 1970's it appears as though there is just one group of players, at which point they become three. Then, over the following 40 years these groups seems to just get heavier - most likely a response by teams to maintain heavier players than their opponents in certain positions.

While the general growth over time makes sense, I wonder what caused the shift specifically in the 70's.

Re: NFL players: height and weight over time

#24
I'd be interested in a similar chart for rugby union where my guess is that the increase in height and weight has happened more quickly. It's just a hunch but I am guessing that overall size in rugby has increased dramatically since the sport went professional in 1995.

Re: NFL players: height and weight over time

#25
post #10

I wonder if this has compounded the TBI and concussion issue over the years. I think sports medicine in general has gotten much better and the average player is probably bigger and stronger and thus able to hit harder than 20+ years ago...

Malcolm Gladwell has looked at this issue[1]. He sees football as being analogous to dogfighting. Popular at the time and with fans, but the science behind it is scary.

I've experienced a severe traumatic brain injury (sTBI), meaning I've seen many brain doctors. I have seen a neuro-omptomolgist (brain-eye doctor) who sees a football player who can't even add up his checkbook (meaning he can't add, not this his checkbook is too complex). I had a therapist who dated a college football player and eventually saw him as more of a patient than a boyfriend.

A concussion is now defined as seeing bright spots[2] and is classified as a mild TBI. The results from concussions are cumulative[3], and football is one of the sports most prone to concussion[3]. A football block is defined as being good if you see bright spots or having a concussion, and players often play through this[4].

I'll never let my children play football.

[1]:http://www.newyorker.com/reporting/2009/10/19/091019fa_fact_...

[2]:https://en.wikipedia.org/wiki/Concussion

[3]:http://www.sciencedirect.com/science/article/pii/S0140673675...

[4]:http://well.blogs.nytimes.com/2013/11/05/dont-tell-coach-pla...

Re: NFL players: height and weight over time

#26
post #12

Earlier quoted context omitted.

William "The Fridge" Perry was probably the inspiration for the absolutely huge linesmen of today. That separation started a little bit after his seasons with The Bears. http://en.wikipedia.org/wiki/William_Perry_(American_footbal...

Probably not as much as you think, because he really wasn't that good of a football player and made his name as a situational fullback. The Cowboys offensive lines of the early 90s are probably the blueprint for the current NFL offensive lines. Those guys were freaking enormous compared to the average line, and it's the main reason why Emmitt Smith is a household name.

No question those guys were bigger. Mark Tuinei was 6'5", 310 lbs. Larry Allen was (at the time) 6'3" 325 lbs.

Tuinei was a contemporary with Perry in the mid-late 80's, but Allen wasn't drafted until the mid-90's.

I still say that Perry was an inspiration. :)

edit Fix team name. Ooops.

Re: NFL players: height and weight over time

#28
post #13

What sort of method would be used to cluster those, statistically speaking? Like, given a data set like that, how would you determine if the distribution is multi-modal or unimodal?

Mean shift clustering, for one. This short PDF provides better insight than wikipedia. Does NOT require you to specify the number of clusters like in K-means:

http://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/TUZE...

http://en.wikipedia.org/wiki/Mean-shift

Example python code using scikit-learn: http://scikit-learn.org/stable/auto_examples/cluster/plot_me...

Re: NFL players: height and weight over time

#29

What's interesting is before the 1970's it appears as though there is just one group of players, at which point they become three. Then, over the following 40 years these groups seems to just get heavier - most likely a response by teams to maintain heavier players than their opponents in certain positions. While the general growth over time makes sense, I wonder what caused the shift specifically in the 70's.

So, weight training and anabolic steroids really take off in this time period. The added strength probably means players can still move that massive body weight at the same speeds (or, in most cases, much, much faster) than someone who doesn't add bulk muscle as modern NFL players do.

NFL players are absolutely, positively freakishly fast for their size.

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