Dynasty fantasy football: Age tendencies of the top running backs
We know that running backs don’t age well. In fantasy football, investing in an aging running back is always a questionable decision. In dynasty, it’s even more fraught with peril. It means younger backs go at a premium, but it also means that, if you find the aging running back who can maintain his production, you can find a short-term bargain.
Thursday, we looked at age data for quarterbacks since 2007 to glean some helpful tidbits for dynasty leagues. Today, we’re running the same research for running backs, with the primary change being that we’re looking at the top-24 backs each year instead of the top-12.
How old are the best running backs? When should you stop looking at them as an investment? Let’s take a look.
(All ages are the player’s age as of Dec. 31 of the given season.)
The average top-24 running backs over the last 12 seasons is 25.7 years old, almost four years shy of the average top quarterbacks in the same span. There are two things that are even more interesting (at least to me):
- The top-12 have been younger than RBs 13-24 in nine of the last 12 years — including each of the last five — and the gap has been more than a year in the top-12’s favor each of the last two years.
- Our average age of the top-24 is going down. The age peaked at 27.1 years in 2013, but has steadily fallen since, down to a 12-year low of 23.5 years in 2018. That includes a whopping 13 first-time entries in the top-24 last year, the most in our sample.
The average age is only one small piece of data, though. Better to look at how it breaks down by age.
It’s not a perfect bell curve, but it’s not that far off, either. As a cohort, running backs peak early, stay good for a while, and then deteriorate quickly around the late 20s and 30s until there are only the Adrian Petersons, Darren Sproleses, and Frank Gores left.
When do they first develop?
As indicated above, guys who might one day reach the top-24 do it early, with 77% of the 101 backs who ever reached the top-24 first doing so by age 25, and 95% doing so by age 28. The only running backs in our sample to reach the top-24 for the first time by age 29 or later were:
- Kenny Watson (RB13) in 2007 at age 29;
- Justin Forsett (RB9) in 2014 at age 29;
- James Starks (RB20) in 2015 at age 29;
- LeGarrette Blount (RB9) in 2016 at age 30;
- Kevin Faulk (RB21) in 2008 at age 32
There were 18 more backs who made the list for the first time at ages 26-28. In other words, if a back hasn’t made the top-24 in PPR by the end of his 25th year, there’s a really good chance he’s never getting there.
In the study on quarterbacks, guys who reached the upper echelon at a super young age were inconsistent. Those who first got there at 22 or 24 years old went on to have more top-12 seasons in only about 20% of the years they were on active rosters, while 23-year-olds were up around 60%. Ultimately, the samples are so small that we can’t say much, except that it’s inconsistent.
For running backs? Things are far more predictable.
A running back who reached the top-24 as a 21-year-old is pretty obviously something special, and the particular specialness fades as the first-timer ages. (The little spike at 28 years old is only six backs over a total of 25 seasons.)
Now, that’s just first-timers who ever went on to do it again, so it’s limited. So to continue, I looked at all seasons. If a back finished in the top-24 as a 24-year-old and had 10 more seasons after that, his percentage of seasons as a top-24 back after that counted. If the same back did it again at 26, his percentage out of his eight remaining seasons was counted.
Here, more than anything else, we see how important it is to reach the top-24 threshold early in a career. Backs who did it at 21 and/or 22 did it again in more than 50% of their remaining seasons (before even considering the fact that four such backs in 2018) with a pretty steady fall to 33-year-olds, who went on to only reach the top-24 in one of five seasons from Fred Jackson (0-for-1), Darren Sproles (0-for-2), and Frank Gore (1-for-2).
At quarterback, guys who reached the top-12 early had a lower percentage. There were flashes in the pan who got extended play just to see if they could recapture the magic. But at running back, it starts hot and cools off. There are two reasons for this. First, backs who get serious play early usually do so because teams are pretty sure of their skill to begin with. And second, as has been shown time and again, the single greatest indicator of running back fantasy success is opportunity. Quarterbacks have more of a performance threshold to cross, but for a running back, if you get snaps, get touches, you’ll get fantasy points.
A staggering 13 different running backs had their first top-24 fantasy season in 2018. The oldest was James White, at 26, while the youngest was 21-year-old Saquon Barkley. Only White and T.J. Yeldon, at 25, clocked in at over 24, while six of the backs were 23 or younger.
Whether they’ll all continue on this road obviously remains to be seen, but the only backs on the list who might be long shots to return are Yeldon, maybe White, and maybe Kenyan Drake. Otherwise … well, it’s a good time to be a young running back.
Who could get there
Remember like five words ago, when I said it’s a good time to be a young running back? Well, the list of backs who could still reach the top-24 who haven’t yet includes (in addition to the impending rookies) Dalvin Cook, Austin Ekeler, Kerryon Johnson, Sony Michel, Royce Freeman, Kenneth Dixon, and more. Dixon, who just turned 25 in January, is the oldest of that group. With Adrian Peterson and Frank Gore nearing the end of their runs, the door is wide open for a massive crop of backs.
Drafting in a dynasty startup for 2019? The running backs you want probably won’t be a surprise. Saquon Barkley is coming off an RB1 season as a 21-year-old. Christian McCaffrey has been top-10 his first two years and will be 23 this season. Alvin Kamara. Ezekiel Elliott. Even Todd Gurley will be only 25 this season and has been top-24 four seasons in a row.
The moral of the story at the running back position? Youth will be served, always, and there’s a lot of youth in 2019.