This is one of my favorite times of the year regarding football. The college football playoffs have concluded, a new champion has been crowned, and new recruits are being signed. In the NFL, the Super Bowl has been played and a new Super Bowl Champion has been crowned. All attention now turns to the NFL Combine and the upcoming NFL Draft. As with the past NFL Combines, body composition will be assessed using dual X-ray absorptiometry (DXA). Players will be scanned and at the end of each day all the scans are analyzed, and reports are generated by position for each of the 32 teams. Pundits predict what players each team will draft.
 
Although the Dexalytics site (https://www.dexalytics.com/news/) contains several blogs on a variety of issues pertaining to DXA, as well as specific topics regarding athletes and a number of sports, there are over 20 blogs pertaining directly to football.  If you are interested in body composition and football, be it college or professional, I suggest you check out these blogs. Since 20 blogs may be a lot for you to read, I have compiled a list of my 5 favorite blogs specific to football on Dexalytics. These blogs provide a great starting point to learn a little about body composition and football.  

1. The Muscle-to-Bone Ratio in NFL Players Compared to Healthy Aged Matched Controls-Part I
The muscle-to-bone ratio (MBR) has become a topic of interest in the world of both collegiate and professional football. Several football teams are starting to use MBR to make decisions regarding the optimal weight an athlete should weigh. This blog explores total as well as regional measures of MBR determined using dual X-ray absorptiometry (DXA) in NFL players (n=346) and compares these results to a group of healthy aged-matched males (n=228).

2. The Muscle-to-Bone Ratio in NFL Players By Position-Part II 
This is a follow up to first blog on muscle-to-bone ratio (MBR) that compared total as well as regional measures of MBR in NFL players to a healthy male control group. While this second blog examines total as well as regional MBR in the NFL players by position. The NFL players were into one of nine position categories: defensive backs (DB: n=64), defensive lineman (DL: n=47), linebackers (LB: n=48), offensive lineman (OL: n=38), quarterbacks (QB: n=21), running backs (RB: n=29), tight ends (TE: n=27) and wide receivers (WR: n=55). Punters and place kickers were combined into one category named punters/kickers (PK: n=17). Although no differences in total MBR were noted across position leg MBR varied among NFL players by position. It is possible that regional differences in MBR in the NFL players may be related to the demands of that position.

3. Normative Data In College and NFL Football Athletes Using DXA (Offense)
The blog was based on two scientific papers examining body composition in 467 NCAA Division 1 collegiate football players and 342 NFL football players. This blog compares body composition between collegiate and professional offensive players. It is the only place that really compares collegiate and NFL players by offensive positions.

4. Normative Data in College and NFL Football Athletes Using DXA (Defense)
This is a companion to the previous blog, but instead of looking at offensive players, this blog focuses on defensive players. This is a great blog if you are interested in the defensive aspect of collegiate and professional football athletes and the only place where you can compare these two groups of football players directly.

5. Changes in Body Composition Over A Collegiate Football Career
This blog examined data from over 700 NCAA Division 1 collegiate football players, who were scanned over the course of their collegiate football careers.  A total of over 2,500 scans were used in this analysis. This blog reported that over the span of 4 years the percent body fat increased in players from years 18-19 years of age, but after that remained relatively constant.  Lean muscle mass on the other hand tended to increase each year.

As I indicated above, these blogs provide a great introduction to body composition and football. If you want to delve father into the science these blogs are based upon, the scientific papers are referenced below. They will provide you with the science that went into these blogs as well as Dexalytics.

References
Dengel DR, Evanoff NG: Positional differences in muscle-to-bone ratio in National Football League players. International Journal of Sports Medicine 44:720-727, 2023.

Wichmann TK, Wolfson J, Roelofs EJ, Bosch TA, Bach CW, Oliver JM, Carbuhn A, Stanforth PR, Dengel DR: Longitudinal assessment of NCAA division I football body composition by season and player age. Journal of Strength and Conditioning Research 36(6):1682-1690, 2022.

Bosch TA, Carbuhn A, Stanforth PR, Oliver JM, Keller KA, Dengel DR: Body composition and bone mineral density of division 1 collegiate football players: a consortium of college athlete research study. Journal of Strength and Conditioning Research 33(5):1339-1346, 2019. 

Bosch TA, Burruss TP, Weir NL, Fielding KA, Engel BE, Weston TD, Dengel DR: Abdominal body composition difference in NFL football players. Journal of Strength and Conditioning Research 28(12):3313-3319, 2014.

Dengel DR, Bosch TA, Burruss TP, Fielding KA, Engel BE, Weir NL, Weston TD: Body composition of National Football League players. Journal of Strength and Conditioning Research 28(1):1-6, 2014.

About the Author
Donald Dengel, Ph.D., is a Professor in the School of Kinesiology at the University of Minnesota and is a co-founder of Dexalytics. He serves as the Director of the Laboratory of Integrative Human Physiology, which provides clinical vascular, metabolic, exercise and body composition testing for researchers across the University of Minnesota.