Observations from around the league
Seattle
Eddie Lacy appears healthy, but the injury/ surgery to his ankle appears to have sapped him of his previous burst. He still runs “heavy” and may be difficult to tackle, but his speed/ elusiveness appear diminished.
Thomas Rawls was clearly favoring one side over the other during his brief preseason action, and didn’t appear healthy. I didn’t study him closely, but at this point it’s an open question whether he can stay healthy with a heavy workload.
Chris Carson appears both healthy and explosive. His posterior efficiency is noteworthy- both lumbar and thoracic areas show strong posterior independence and fluidity. Carson does show certain notable anterior lumbar/ thoracic inefficiencies, but it is becoming increasingly apparent that posterior efficiency trumps anterior efficiency for RBs.
Carson therefore seems likely to be featured on Seattle’s offense at some point this season. He shows reliable hands, and explosive running. In addition, in preseason week 3, he seemed to show good recognition/ chemistry with Russell Wilson.
Last year, Russell Wilson appeared poised to continue his dominance from late-2015. However, he suffered an injury in week 1 which severely affected his mobility and throwing mechanics. This year, he appears fully-healthy and ready to pick up where he left off in 2015.
Tennessee
Eric Decker appeared far from healthy in preseason. His recovery from shoulder/ hip surgeries was not yet complete, and it is difficult to evaluate Decker’s timetable. It’s also possible he may not fully recover from his recent injuries/ surgeries.
Rishard Matthews therefore seems likely to remain the offensive focal point at WR for the time being. In what is becoming a theme of this article, posterior efficiency seems to be the greatest predictor of continued health/success at the offensive positions QB, RB, and WR. And Matthews shows high levels of posterior lumbar/ thoracic efficiency (coupled with noticeable anterior inefficiencies).
Chicago
Jordan Howard shows (guess!) high levels of posterior efficiency, coupled with some anterior inefficiencies. He looks likely to continue running very effectively.
Kendall Wright appeared to be Mike Glennon’s preferred target in preseason. He shows high levels of anterior thoracic/ lumbar efficiency, and is running routes with speed and precision.
Dallas
Dak Prescott appears to have added an accurate deep-ball to his throwing repertoire. Given that his high level of posterior-thoracic efficiency allows a very consistent throwing trajectory (constrained only by the patterns of anterior inefficiency that he continues to mold to his advantage), Prescott may actually increase his statistical output with a wider variety of throws at his disposal. At the very least, a sophomore slump seems unlikely (barring future injury).
San Die, I mean Los Angeles Chargers
Travis Benjamin was one of the top deep-threat WRs in the league for the first half of 2015. He then suffered shoulder and hamstring injuries in 2015/16, which significant reduced his speed/ route-running ability.
Surrounded by other high-quality WRs and with an accurate QB in Rivers, Benjamin appeared fully healthy in preseason, running at top speed, and ready to resume his early 2015 form. I expect him to be running loose in many secondaries for as long as he stays healthy (which may not be long, given his still-tight posterior shoulders/ hips).
Rookie RBs
Dalvin Cook shows very high levels of anterior lumbar efficiency. His posterior system is developed along the core, but does not show much overall independence. He appears very quick to follow his blocks and able to squeeze through small holes. And he shows high levels of thoracic efficiency, with excellent hands. But his somewhat lacking posterior efficiency translates as an inability to run through the defense- I don’t think he will post an elite yards-after-contact average.
Christian McCaffrey shows some of the highest levels of anterior lumbar efficiency I’ve studied, and also shows very high levels of cervical/ thoracic efficiency. His one relatively-inefficient area appears to be his posterior lumbar area. He therefore projects as an extremely capable athlete, albeit one who won’t be breaking many tackles (just eluding them).
Leonard Fournette shows very high levels of lateral posterior lumbar efficiency, with his medial posterior lumbar system appearing slightly compromised. His anterior lumbar system appears a bit under-developed. Fournette therefore shows strong leg-drive, but a tendency to crash into tackles, rather than bounce off of them. His thoracic efficiency is not particularly high- he seems unlikely to contribute heavily as a receiver. Overall, he appears likely to have a successful early-career, which may become compromised by his tendency to take big hits.
Chris Carson may be this year’s David Johnson- a relatively unheralded back coming out of college, who becomes a high-level featured-back by the end of the season. His significantly-efficient posterior lumbar system (both medial and lateral) is genuinely noteworthy. And posterior lumbar efficiency appears to be the single most likely biomechanical predictor of success at the RB position.