Do Older Quarterbacks Wilt In December and January?

Well argued Bill.

I'd argue also that many quarterbacks who play beyond 35 have proved themselves more physically durable than others. 35+ year old quarterbacks are mostly physical anomalies themselves, i.e. Vinnie, Brett, Flutie. Plus, I'd say that many 35+ QBs, while not necessarily physical freaks like Vinnie or Brett, have not been subjected to first-string QB abuse their entire career. Flutie, Kerry Collins, Kurt Warner, etc all spent time either away from NFL football (or football altogether) or were bench jockeys for a substantial portion of their career. Riding the pine certainly helps to preserve you and prolong your career.

Interesting subject matter.

...still probably worth a more thoughtful look, though:

1) Is 35 the right age? For positions dependent on power and speed as their primary athletic attributes it may be earlier. QB is about throwing ability (what's the rule of thumb for pitchers in baseball?) and judgment / game-management. For modern athletes, that age cutoff might be a couple of years higher at 37 or 38 before there's a real effect.

2) As you rightly point out, there's a winnowing process, and anyone playing anyRothing in the NFL well into their 30's is pretty good at what they do. Therefore, maybe you need a longitudinal study against the same population of quarterbacks. Take the population of 35+ quarterbacks performance at 35+ and compare it to when they were younger. What does that tell you?

Not so much looking to criticise the study, as I think the results are about right. Purely as a matter of interest ... what are the sample sizes?

I'm struggling to think of too many regular starting QBs over 35 in recent years ... Rich Gannon, Brett Favre er ... um ... even Steve McNair doesn't qualify.

But I guess back in the late 1990s - Jim Kelly, Dan Marino, John Elway, Steve Young, Doug Flutie must make up a bulk of the reps ... with the latter two getting significant backup reps more recently ...

Was there a youth-movement effect earlier this decade?

What if, instead of age, you look at seasons played? As Joe T. pointed out, a lot of QB's playing at age 35+ took some years off before then. If we're worrying if old bones and joints feel the cold more, maybe the question is not how old they are, but how much punishment they've taken.

I'm wondering if there's some warm weather or dome effects going on here. Is there any way to break it down by location of the game as well? (Generalizations like New England is always cold/San Diego is always warm are probably fine.)

Not sure how you'd reliably measure mileage. There's precious little data on QB hits and hurries the farther back we go and even for sacks, pre 1980 or so... nothing reliable.

Which QBs have played every game this year? Do they all have the same mileage from those 16 games? I'd argue no. Manning, with only 12 sacks, has been pounded. Ben R,with 99 sacks against him, has been pounded more. With a super running game and solid OL, I assume Eli has not taken too much of a beating. Brady, who only played one quarter of one game suffered an injury that might, to some, mean his year was pretty low on the pounding scale... of course it could also negatively affect every throw he makes from now til the end of his career as well. Time will tell

Might as well go with age--at least it's objective and measurable. And as we see, doesn't matter all that much. An NFL QB is an NFL QB. There are probably more stiffs in the 22-28 age range (backups thrust into the limelight for their one chance to do well) than there are guys at 35 (if you're a 13-year veteran QB, you clearly do not suck. You might not be what you once were, but you are better than most first-time starters who were backups the week before. The old guys usually have *something* whether it's craftiness, a cannon arm, quick release, etc. even if other aspects of their game have faded.)

Don't really young QBs also conventionally struggle in the postseason? If you look at that chart, it would seem to bear out that the postseason is least hard on guys in their late 20s, which is what one would expect if there were a "rookie wall" and a "veteran wall," no? This would seem to say that Rivers and Roethlisberger would seem to be in good shape on this particular metric.

What, if any, impact would "meaningless" Week 17 games have? Or would the number of meaningless games for the old QB's teams vs meaningless for their opponents cancel out? Perhaps the last week of the season should be removed?

I think that there is a conceptual problem with this study.

You are assuming that late season older QB's are the same people as early season old QBs, and that might not be the case.

So, yes it is true that older QB who start early in the season are likely pretty good. But what about veteran backups for injured projected starters? If you Flacco or Ryan had gotten hurt, who would have started for these teams in December? Heck, look at Vince Young and Kerry Collins. Is Collins really that good? No, of course not. He's a competent veteran backup.

Competent veteran backups are old, almost by definition.

And so, you've answered the question about the groups (old QBs, young QBs), but not whether individual old or young QBs get better/worse in the cold.

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So, how to fix this?

1) Well, you still want a good sample size, and so you still want individual game ratings. Fine.

2) You need to somehow correct for whether each game is better or worse that THAT QB did the rest of the season. That's pretty easy. Use the difference between their season's rating and their game rating as you individual data points.

3) Run the same averages.

This would tell you whether individual QBs get better or worse, on average, grouped by age. QBs who only played part of the season (e.g. Vince Young) would not affect the numbers. It would automatically remove the impact of late season "let's see what he's got" starts for young QBs, or late season replacements by veterans who didn't start at all early in the season.

You'll see any trends clearly, if they exist. If you run columns for each month, you'll be able to see if the youngest (i.e. <25) QBs actually improve, or where the big jump or The Wall is.

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You could also easily run this by years experience (easy to get), which might get you some different stuff. Heck, you might be able to run it by games experience, but that might be harder. (Obviously, I am thinking more about young QB development here.)

Another relatively easy one might be to look at what start it is of the year for that QB. That is, address the "wisdom" of the idea "he can fill in for a couple of weeks, but that's about it." Do younger QBs hit a wall at a certain start in the season? Do older QBs wear out around week 13?

It would be harder to add game time temperature, but that IS possible. That's really the question, isn't it? Comparing younger QBs performance in cold weather games to their performance in warm weather games, and comparing that comparison to older (or just old) QB's comparison.

comparison comparison comparison

So, if you want to do the article, try different versions of the question.
IV variants #1 : Age, experience, games started (career), game started (season).
IV variants #2: Month, week, start # (in-season)
DV correction: rating(week) - rating(season) -------------- instead of rating(week)

Am I reading this right? Drop-off of old QBs = 2.6% vs 2.5% for younger QBs. That's a differential of 0.1% .. is that even statistically relevant? IMHO - I just don't see any performance difference in the 2 groups.

Actually, if you look at the original breakdown, it looks like there is a "sweet spot" of age between 27 and 30 where there is no drop off in production. All the other age brackets show a 2.5% to 3.5% decline.

One could argue that in their prime years, QBs do not see a decline, but in any other age range, they do.

A couple of years ago I did a study on the careers of all Hall of Fame and probable future Hall of Fame QBs who entered the league after WWII. One of the things I was interested in was how age affects the quality of the QB. Since all of the guys in the study are among the elite, there is no bias for better QBs playing at a greater age just because they win that right be being great earlier.

My findings were that passer rating, completion percentage, and yards per attempt remain virtually unchanged for as long as an elite QB cares to play. However, after 16 seasons in the league (age 37 or so), total yardage and TDs per attempt begin to drop and really drop by season 18. I think the reasons for these observations are that older QBs are very savy, having seen virtually everything a defense can throw at them, but on the other hand the wear and tear on the arm and shoulder after 16 seasons in the NFL take a toll. Older QBs are generally smart enough to limit mistakes, but stamina has become an issue, which would indicate a tendency to fade a bit late in the season.

Is the study supposed to show the effects of a long season ? In which case shouldn't the study only consider QBs with 10+ passes in all 16 games.
Also, the data presented indicates that quarterbacks do indeed tend to wilt in the late season as they get older. Once a QB gets to age 27 they show a definite decline as they get older.
The more interesting question seems to be "Why do young QBs also fall off over the long season ?"