ShaHBucks said:
Biabreakable said:
ShaHBucks said:
Hopefully I can be a voice of reason here. I kind of agree with everbody to some extent. 5'8-10, 200 +/- pounds used to be the normal for RBs awhile ago. In 2009 Sankey would have the profile of a 1st round pick, like Donald Brown. That isn't the case today because these small/speed backs are a dime a dozen and flop more often. The NFL is getting bigger. The guys that are 20-40+ pounds who run 4.5 are in demand because a lot of the smaller backs get hurt too often and can only run off tackle. Therefore, they get drafted as role players of get buried behind bigger backs like Jonathan Franklin was last year. Either that or you're a role player like Gio.
Sankey might be different though. He gets an upgrade for his strength. 26 reps on the bench for someone his size is impressive. There isn't too many backs (215 pounds or less) that has his speed-agility-strength combo. That doesn't mean he's guaranteed success. Guys his size are not taking a ton of carries because they can't move piles. Guys his size are not dominating the NFL right now unless they run in the 4.2-3 40x. LeSean McCoy is the outliner. We have to see where he lands to dictate who he'll be statistically. My only fear is he yeilds goal line touches to someone and isn't really a workhorse.
What evidence do you have to suggest the NFL is going bigger now as compared to 2009?
From my perspective the NFL has always seemed to prefer bigger players but those players tend to have shorter careers and do not sustain their performance as long as the smaller RB do.
To say that a smaller RB can only run outside is not correct either. Too many examples of this not being the case.
Look it up. The training and nutrition programs player are on from HS to the pros get better over time with science. Just following recent trends, bigger backs or 4.3ish runners are what works right now.Give me "too many" examples of recently drafted small RBs who are workhorses, taking goal-line carries and pushing piles today.
I have looked it up. Every season I look it up. Your assessment is incorrect.
You made the statement. It is not on me to prove it wrong but on you to back your statement up with some facts. Something you repeatedly seem unwilling to do. That bothers me.
Draft probabilities by position
Some interesting excerpts from this article-
• Smaller Running Backs (210 pound or less)
• Larger Running Backs (over 210 pounds)
I am not sure why this cut off is at 210lbs. I am noticing the same thing from similar discussion with EBF.
What is so special about 210bs?
Selections 1-13
• Average % of five-year starters: 71.3%
• Among playing positions with at least 10 players drafted with these selections during the study period, the probability of drafting a five-year starter ranged from 60% to 95%
• Least risky: Offensive linemen (95%, or 20 of the 21 offensive linemen selected from 1994 through 2008 became five-year starters)
•
Most risky: Large running backs (60.0% five-year starters), but quarterbacks (64.0%) and wide receivers (61.5%) were close.
Selections 14-24
• Average % of five-year starters: 63%
• Among playing positions with at least 10 players drafted with these selections during the study period, the probability of drafting a five-year starter ranged from 36% to 71%
• Quarterbacks, small running backs, tight ends, safeties and inside linebackers had too few selections to consider as part of the discussion
• Least risky: Offensive lineman with 71% of draftees becoming five-year starters
•
Most risky: Large running backs with 36% of draftees becoming five-year starters
This is why I tend to downgrade larger RB because they carry more risk of shortened careers than smaller quicker RB.
What I didn't know is that small RB drafted after pick 24 carry just as much if not more risk than the big RB.
Selections 25-46
• Most risky: Small running backs (16.7%), large running backs (23.5%)
Selections 47-73
• Most risky: Quarterbacks (8%), small and large running backs (combined percentage of 11%)
Small and Big RB are lumped together here as such a small percentage of either have 5 year careers.
Observations:
• Not many small running backs are taken with early selections
• There is a low likelihood of grabbing a starter at any point in the draft but players in this group often return kicks
• The probability of drafting a five-year starter is lower than the average for each draft choice range.
Observations:
• Drafting running backs is a risky propositions and the percentage of five-year starters is below the average in every data choice range
• Only two of the 92 large running backs selected after the 114th pick ended up as a five-year starter
• The probability of having a five-year career is considerably lower for large running backs than the average of all positions.
Jonathan Bales
Exploring Running Back Size
Wednesday, April 02, 2014
http://www.rotoworld...-back-size?pg=1
Jonathan Bales is the author of the Fantasy Football for Smart People book series. He recently launched RotoAcademy - a fantasy football training school.
I was having a conversation with my dad the other day and I asked him to name the top four wide receivers in football with whom he’d want to start a team. He said
Calvin Johnson,
Josh Gordon,
Dez Bryant and
A.J. Green. I agree with three, subbing in
Demaryius Thomas for Green (although it’s close).
Then I asked him to name the top four running backs with whom he’d start a team.
LeSean McCoy was an immediate choice. He contemplated
Jamaal Charles and
Adrian Peterson, but in running back years, they’re basically dead.
Matt Forte was on his list, as was
Marshawn Lynch -
Marshawn Lynch! - and
Le’Veon Bell.
If that list sounds ridiculous to you, it’s because 1) it kind of is and 2) it’s really, really hard to figure out which running backs are the best ones. We can immediately identify the top wide receivers in the NFL, but that task is exponentially more difficult for running backs. If we’re incorporating age into our assessment - which we should since it matters in both real life and fantasy - who the hell are our starting four? I’d likely still throw Charles and perhaps AP in there with McCoy, but I seriously have no idea who is the fourth-best back in the NFL.
In short, we know that
Julio Jones and
Dez Bryant and those studs are better than second-tier receivers like
Jordy Nelson and
Eric Decker, who are in turn better than guys like
Brandon LaFell. But outside of a couple obvious talents at running back, can we really know that the consensus No. 25 running back is any worse than the No. 5 player at the position? How good is a player like
C.J. Spiller? I legitimately considered putting him in my top four, but I have a feeling that most people might not have him in their top 15 or 20.
When it comes down to it, running backs are just so dependent on their teammates for success that it’s really difficult to isolate their play and figure out how good they are. They’re difficult to project out of college and their NFL stats are only loosely tied to their actual talent.
That’s one reason I’ve been going against the grain in advocating a late-round running back strategy as of late, but it’s not like we can just draft only rookies at the position (maybe). Running back is still very important in the fantasy realm, so what can we make of the position?
Running backs are always going to be dependent on heavy usage for substantial production, but we still need to figure out some way to predict which ones are going to be useful when they get opportunities.
Running Back Size
Heading into this analysis, my hypothesis was that shorter, heavier running backs would have more success than taller, lighter ones. I was really interested in the height data because I’ve had a suspicion that shorter backs are generally better; they’re usually more agile, quicker and have a low center-of-gravity which is crucial at the position.
Related to both height and weight is body-mass index (BMI). Using BMI to judge overall health is absolutely asinine - pretty much every NFL player falls into the ‘obese’ category - but it’s still a good measure of how much bulk a running back possesses; a 5’10” back who weighs 210 pounds is bulkier and has a higher BMI than a 5’10” back who weighs only 190 pounds. The taller a player, the more difficult it is for him to have a high BMI. So I’m really looking to test three things - height, weight and body mass - and how they affect NFL performance.
The first thing I did was test the correlation between those three traits and a trio of stats - carries, yards-per-carry and touchdowns - for all backs since 2000 with at least 300 yards rushing. Here are those r-values. (see link for graphs)
The initial numbers suggest that height doesn’t affect NFL performance all that much for running backs (more on that later). Taller backs get a few more carries than shorter ones, they have a few more touchdowns, but they’re generally a bit less efficient in terms of YPC.
Meanwhile, take a look at weight and BMI. Neither affects workload very much - meaning we’ve already determined we can’t use running back size to predict rushing attempts - and they’re both weakly correlated to touchdowns. We’d expect bigger, heavier backs to score more touchdowns just because they see more goal line attempts, though.
But take a look at the effect of weight/BMI on rushing efficiency. They’re pretty strongly negatively correlated, meaning as weight increases, rushing efficiency decreases. This was at first a surprise to me because we wouldn’t expect heavier backs to be worse.
I overlooked an important fact, though; generally, heavier backs are slower than light ones, and speed is incredibly important to running backs. I’ve shown that the 40-yard dash matters more for backs than for any other position. Here’s a refresher that breaks down running back
approximate value according to combine 40 times.
I value speed in running backs even more than other stat geeks; if a running back doesn’t run sub-4.55 (regardless of his weight), there’s very little chance I’ll draft him. If he’s very light, his little frame better be accompanied by blazing speed.
The fact that heavy running backs are much worse than lighter ones isn’t surprising when you consider the differences in speed. So does extra weight hurt a running back? No, with two caveats: 1) he isn’t just eating Wendy’s and the “extra” weight is lean muscle and 2) his speed remains unchanged. I’ll take a 220-pound back with 4.45 speed over a 200-pound back with the same speed all day. Weight is good, it’s just not as important as straight-line speed.
Now, let’s get back to height…
Height and Running Back Success
The correlations suggested that, as a general rule-of-thumb, taller might not be worse for backs, but there’s another way to analyze the data - sorting it into buckets. I like to do this because it helps see how performance changes at certain thresholds. And when we do that with height, we see a different story for running backs.
I sorted all of the data into quantiles for height, weight and BMI.
We see a steady decline in YPC with weight; the lightest quarter of all backs has been the most efficient, followed by the 26th-50th percentile, and so on. The BMI effect is similar, with a very rapid decline after the bottom quarter.
Very quickly, I want to mention that there’s probably a little bit of a selection bias here with lighter backs getting a higher quality of carries. When a running back gets a carry on third-and-10, he usually gains a decent number of yards, and he’s also usually a fairly light third-down back. However, such carries are pretty uncommon and the results are very strong, suggesting that the real culprit is simply heavy backs being slower.
I’m going to bold this sentence and say it again: the best running backs are fast.
Now, look at height. Remember that the correlations showed that height might not matter too much for running backs, but what we really see is that the bottom 75 percent of running backs in terms of height perform right around the same in terms of efficiency. Meanwhile, the top 25 percent - the tallest quarter of running backs - have rushed for fewer than 4.0 YPC since 2000. That’s horrific.
To me, this is clear evidence that height doesn’t matter all that much for running backs … to a point. And that point is right around 73 inches, or 6’1”.
Now let me just address the criticism sure to come to everyone’s minds: BUT ADRIAN PETERSON IS 6’1”! Yes, that’s true. As is the fact that
Arian Foster ran a 4.68 in the 40-yard dash,
Jerry Rice was also quite slow,
Warren Sapp dominated inside despite shorter-than-average arms and lots of other cases of players becoming exceptions to the rule.
My goal isn’t to get every prediction correct, but just to tilt the odds a little bit. And the numbers suggest that, as a general rule-of-thumb, we should prefer shorter backs over those who stand well above 6’0”. That doesn’t mean we need to avoid every tall running back. In the case of
Adrian Peterson, it’s kind of difficult to hate a 217-pound back with 4.40 speed. But if another back were similar to Peterson - 217 pounds with 4.40 speed and a comparable skill set - but he checked in at 5’10”, we’d be smart to favor the shorter back.
All other things equal, we should seek running backs 6’0” or shorter.