There are a lot of stats out there that purport to give you an edge in your fantasy leagues. With more and more fantasy analysis out on the internet and more and more people looking for new ways to judge players, it becomes difficult to sort through how much certain statistics really matter in judging a player's fantasy impact. Advanced stats are great in many cases, but sometimes...well, sometimes they don't seem to jive at all with the eye test. One of those stats is the rushing efficiency stat from the NFL's Next Gen stat tracking program. Here's how the NFL defines that statistic:

Efficiency (EFF)Rushing efficiency is calculated by taking the total distance a player traveled on rushing plays as a ball carrier according to Next Gen Stats (measured in yards) per rushing yards gained. The lower the number, the more of a North/South runner.

So, essentially, the statistic wants to show which running backs use their carries efficiently--who gets the most rushing yards while running for the least distance. In theory, backs will stay fresher if they're more efficient because they'll expend less energy while rushing. By this logic, fantasy owners would love to have efficient backs because they'll be able to take on a higher workload. Does it actually work that way, though?

Get any full-season NFL Premium Pass. Exclusive access to our Premium articles, rankings, player projections, 15 in-season lineup tools and daily Premium DFS research/tools including our Lineup Optimizer, Research Station and so much more! Sign Up Now!

Efficiency Numbers

Let's take a look at last season's leaders in the category:

Now let's take a look at the bottom ten players in the category:

Now, right off the bat you might notice a few things. First, Alvin Kamara ranked as the most efficient running back and Tarik Cohen ranked as the least efficient. These two things seem to line up pretty well with what we know about the two backs: Kamara succeeded as a rookie because of his quick burst and ability to get up field, whereas Cohen struggled at times because he had to run sideways to avoid contact.

But, let's dive a little deeper. Here are where all 20 of these running backs finished in standard scoring leagues last season:

Top 10 Efficient Backs

Now, take some of these with a grain of salt. Darkwa, Morris, Drake, and Williams didn't start the year at the top of their team's depth charts. The backs who finished both top ten in this metric and as top 12 running backs--Kamara, Lewis, Ingram, and Hunt--show some of the usefulness of this statistic, and players who received some mid-season hype--Darkwa, Morris, Drake, and Williams--rank highly here too, supporting the idea that...uhh...what idea does this support? Efficient running backs are good to own? But didn't just three of the overall top 10 backs make this list? That means this measure doesn't accurately predict who will be among the best backs in a given year.

What use does this list have, then? It might be useful in predicting which back-up running backs will move into larger roles as the season goes along, but it isn't going to help you figure out how they'll perform once they're in that role. Darkwa finished third in this metric, but he didn't display much consistency on a game-to-game basis. You could have looked at the efficiency numbers, made a move for Darkwa, and been rewarded with his 20-carry, 154-yard and a touchdown performance in Week 17, if you were still playing fantasy at that point. You also could have been sorely disappointed by a six-carry, 10-yard Week 16 or a nine-carry, seven-yard Week 15 game (though he did at least find the end zone in that one).

Bottom 10 Efficient Backs

Okay, now we're getting somewhere! Only one top 10 fantasy back, Jordan Howard, ranked among the 10 least efficient backs. A lot of his fantasy value was based on his volume, as the Bears were forced to run the ball over and over and over and over during quarterback Mitch Trubisky's rookie season. The only other top 20 back was McCaffrey, who should have a strong 2018 season. But the other eight? All outside the top 20, and seven of them finishing as the RB40 or worse.

There were some injury issues with some of these players, but we can still extrapolate this information to come to a conclusion: the least efficient running backs aren't successful fantasy backs unless there are specific circumstances that lead to their lack of efficiency. Think Howard running into crowded boxes. Think McCaffrey being known for his East-West running.

Conclusions

I don't want to toss this metric out the window completely. As we move down the list of efficient backs, we tend to see the level of play by these backs decrease. But, it isn't a neat and orderly progression. Talent and situation rule the day as always. Still, we can conclude that fantasy owners should be suspicious of backs who rank poorly in this statistic. Maybe running back efficiency can't tell us which top running backs will perform better--if you need to make a decision between Alvin Kamara and Le'Veon Bell next year, this isn't the statistic to use to make that decision. But if you need more reasons to not trust Doug Martin no matter where he lands or to just NOT DRAFT AMEER ABDULLAH AGAIN, this can help you confirm those suspicions.

Still, it can't be the final piece of evidence you use to make a decision. Jordan Howard wasn't efficient, but it doesn't make him a bad draft pick in 2018. Always consider "why" a player was an inefficient runner. Consider what teams did to address offensive line issues and how coaching and scheme changes will impact these players next season.

More Year In Review Columns