Barry Sanders and Emmitt Smith are arguably two of the greatest running backs of all time. They dominated the 90s with their running styles and were both eventually enshrined in the NFL Hall of Fame. Fans and media folk have often debated “Who was better as a running back”. It is a bit of a tough question to answer. First, stating the obvious, Emmitt played an extra 5 years than Barry. Emmitt played 15 seasons while Barry retired after just ten seasons, most people feeling he cut his career short. Secondly, Emmitt was on some exceptional Cowboys teams and had a supporting cast of great offensive linemen, a solid blocking fullback, and a hall of fame quarterback with great receivers, which set him up for opportunities that weren’t always present for Barry (the Lions only finished first in the, what was then referred to as the NFC Central, twice during Barry’s ten year career).
But what if Barry had played the extra 5 years that Emmitt did? Barry ended his career with 15,269 yards to Emmitt’s 18,355 career yards. How many more could Barry have gotten?
Side Note: I removed receiving yards from this analysis as I only wanted to look at rushing yards. Barry had 2,921 career receiver yards while Emmitt had 3,224 career receiving yards, most of those coming in his first nine seasons with the Cowboys.
First, let’s look at some visualizations of the career both of these superstars had. We will look at their yards per season, their average yards per attempt each season, and their average yards per game each season.
Looking at the graphs, it seems like Barry was a more consistent runner than Emmitt and, after the age of 27, Emmitt’s production began to dip a little bit, while Barry stayed relatively consistent. During Barry’s 10 year career, he averaged 4.98 +/- 0.6 yards per attempt, 99.9 +/- 14.2 yards per game, and 1,526.9 +/- 270.8 yards per season. Looking at the first 10 years of Emmitt’s career, he averaged 4.3 +/- .46 yards per attempt, 90.3 +/- 17.6 yards per game, and 1,396.3 +/- 267 yards per season.
In the last 5 years of his career, Emmit averaged 3.62 +/- 0.5 yards per attempt, 59.42 +/- 19.9 yards per game, and 878.4 +/- 362.6 yards per season. It is important to remember that Emmitt missed six games during the 2003 season due to a fractured shoulder blade, causing him to only get 90 attempts that year (a far cry from his average of 269 attempts per year that he got during that time period, after removing the 2003 season from the data set).
So, how much better would Barry have been had he played the same amount of games that Emmitt played – what amounts to 73 extra career games (since Emmitt missed 6 games in 2003, 2 in 2001, and 1 in 2004)?
In baseball, Sabermetricians will sometimes use the Equivalence Coefficient (EC) as a means of projecting out performance in specific metrics given an equivalent scenario.
First, we determine that, had Barry been given 73 extra games in his career, he would have had approximately 1461 total attempts (based off his previous career numbers). This allows us to calculate Barry’s EC:
1+(1461/3061)*1.00 = 1.477295
By multiplying this coefficient by Barry’s career total yards, 15,269 yards, we project that, given 73 extra games (or 1461 extra attempts) Barry would have rushed for a career total of 22,557 yards (4202 yards more than Emmitt).
Of course this assumes that during these extra 73 games Barry is 100% of the player he was in the past. Oftentimes, people will talk about the the magic age of 27 representing a “cliff” for running backs where their performance begins to drastically decline (it seems like Emmitt may have started to decline around this age). Looking at Barry’s charts above, it certainly doesn’t look like he was showing signs of decreased performance at the age of 27 and there is no reason to believe that he wasn’t going to be the same player in those next 73 games that he was in the previous 153 games. However, let’s assume that perhaps Barry is not the same player in those next 73 games. Looking at Emmitt’s production in his final 4 seasons (I took out the injury plagued 2003 season where he only had 90 attempts in 10 games), Emmitt saw a 16% decrease in average yards per season, a 6% decrease in average yards per attempt, and a 15% decrease in average yards per game. So, let’s say, hypothetically, that during the next 73 games, Barry would be 10% less of the player that he was in the first 10 years of his career (a 10% decline in his overall performance). If this is the case, Barry’s new EC is calculated to be 1.429566 and his projected total for career yards would have been 21,828. That is 3,473 more yards than Emmitt Smith had in his career.
What does it all mean?
It is fun to play with projections like this. This doesn’t necessarily mean that Barry was a better running back (remember, I didn’t factor in receiving yards) but it certainly does show the incredible skills that Barry had and what he was able to accomplish in a career that he ended too soon (in the opinion of many). From a sports science/strength & conditioning perspective, projecting out performance allows us to understand the potential that our athletes have and what their projected performance may look like given a decrease in their overall output. This is important in a team sport as the chaotic nature of performance is difficult to tie back to the S&C coach (it certainly is not as easy to make the connection as it is with an individual athlete sport, such as track and field, swimming, or cycling). With this information we can begin to grasp the value that our programs may have on prolonging an athlete’s career by keeping them healthy and on the field/court where they can perform at the highest level, helping them to maintain their performance without seeing as large a decline with age as other athletes may see.