As a former 190 pound offensive lineman I continue to be amazed at the growth in size at these positions over the last Forty years. When I played (actually sat on the bench in college ? President of Splinter & Nail Society of Elite Benchwarmers, Fresno State Class of 68) someone that was over 260 was considered huge. The blocking rules were different then, you could not extend your arms away from your body. This demanded more precise positioning and quickness, so size was not as important. Now that the athletes can extend their arms the premium is on size, just getting in the way is enough. The bigger the better, the more space the player occupies. Another change is in the substitution rules, in the mid 1960?s substitution was changed from limited substitution where most player had to play both ways ? offense and defense to limited substitution where the player only played offense or defense. This allowed more specialization and demanded less fitness. As this began to take effect the players grew. Today for most offensive linemen, the greatest distance they have to run is on and off the field (slowly)!
The actual weights of the offensive linemen certainly show that the trend is not being reversed. At the NFL Combine from 1989 to 2005 the weight of the linemen has increased significantly, centers went from an average of 275 to 309, guards from 285 to 316 and tackles from 289 to 318. It is interesting to note that their results on the 225 maximum repetition bench press have not increased commensurate with the increase in body weight. The centers went from 23 reps in 1989 to 26 reps in 2005, guards from 22 reps to 27 reps and offensive tackles from 20 to 22. When you express that as relative strength the centers went from 11.96 in 1989 to 11.88 in 2005, guards from 12.95 to 11.70 and offensive tackles unchanged at 14.45.
The question that many people have raised is the long term health effect of carrying the extra weight? The jury is out, but there have been some alarming trends begin to appear. The mortality rate for former NFL payers is higher than the normal population. In my opinion this is a time bomb waiting to go off. The other aspect of this is the effect the added weight has on the joints, especially if the player is unable or unwilling to lose weight after their career is over.