I put this as a diary b/c it is so incredibly long but anyways. I spent the morning expanding the research from any back that's carried to ball 370 times or more to any back that's carried the rock 330 times or more. I also looked up postseason stats and included those for these backs. With that being said, there could be other backs that for example carried the ball 310 times in the regular season and 60 times in the postseason that will not be on this list. The bottom line that I looked at was 330 regular season carries. Expanding the minimum carries more than doubled the `sample size' (49 guys). I'll go ahead and tell you that when I list the number of carries for a back the number of postseason carries is included if in fact there were any for that particular year.
There are some guys that we have to exclude either because there isn't enough history yet or off the field pot problems. Here are the guys that I'm excluding and why:
Stephen Jackson - 346 carries in '06 (his third season), even though he is already injured this year
Willie Parker - 337 carries in '06 (his third season)
Larry Johnson - 336 carries in '05 and 429 carries in '06 (his third and fourth seasons respectively)
Ricky Williams - 383 carries in '02 and 392 carries in '03 (his fourth and fifth seasons respectively)
Rudi Johnson - 361 carries in `04, 350 carries in '05, and 341 in '06 (his 3rd - 5th seasons)
**I will point out on LJ and Ricky that even though they were able to have back to back seasons with that many carries, their yards per carry average fell by .9 and 1.3 respectively. But there isn't enough history for either player to know whether those were just down years or a trend.
Now I'll go one by one and see if the remaining 45 guys are `myth busters' or fell victim to the curse.
Earl Campbell - he's somewhere in the middle as he averaged 385 carries over his first four seasons (1978-1981) but would never again play as a starter for a full season or have a yards per carry average over 4.0.
Wilbert Montgomery - carried the ball 377 times in his third season (1979) but only play one full season over the next six seasons and only break 1,000 yards once more. He played in 12 games the following year (1980).
Otis Anderson - carried the ball 331 times his rookie year (1979) and would break the 300 carry mark and have another 349 carry year in his 12th year (1989). He also had 5 seasons that he played in 9 games or less.
George Rogers - rushed 378 times his rookie year (1981) and 369 times in his 5th season (1986). In the years immediately following those two seasons he combined to play in 17 games and rush 285 times.
Tony Dorsett - had 342 carries in his fifth season (1981) and only played in 9 games the following year. He next three seasons following the 1982 would be productive but he wouldn't carry the ball more than 305 times again.
Eric Dickerson - absolute beast. Enough said? His first four seasons (83-86) he averaged 400 carries a year and only missed two games. He would have one off year (87) then have another 388 carry season.
Curt Warner - he ran the ball 398 times his rookie season (83) and would play in one game the following season. He had four more healthy years but would only break the 300 carry mark once (1986).
William Andrews - had 331 carries in his 5th year (83) then had a serious knee injury that sidelined him until the 1986 season. He would play in 15 games that year and have 52 carries but that would be his final season.
John Riggins -- carried the ball an amazing 462 and 348 times in his 12th year and 13th years (83-84). He would only play one more year but he was pretty old for a running back anyways.
James Wilder - had 407 and 365 carries in his 4th and 5th seasons (84-85) but would never again play a full season or have more than 190 carries.
Walter Payton - he was a beast as well, with 5 seasons with over 330 carries. That combined with the fact that he only had two seasons in which he missed more than 3 games is pretty amazing.
Marcus Allen - in his fourth season he had 402 carries (1985), but he would never again carry the ball more than 259 times and would never break 1,000 yards again.
Gerald Riggs - in his 4th and 5th seasons (85-86) he had 397 and 343 carries but he would never again carry the ball more than 203 times or play a full season again until 1991.
Joe Morris - had 334 and 414 carries in his 4th and 5th seasons (85-86) but would miss 5 games the next year and would never average over 3.5 yards per carry again.
Herschel Walker - had 361 carries in his third year (1988) and would stay remarkably healthy for a running back missing only one game over the next 9 years but would only carry the ball more than 200 times twice.
Christian Okoye - after a 370 carry season in his third year (1989) he never would carry the ball more than 258 times again.
Dalton Hilliard - during the 1989 season (his 4th) he'd carry the ball 344 times but would only play in 16 games over the next two years and would never again top 118 carries
Barry Foster - after a 410 carry season in his third season (1992) he'd play in 20 games the next two seasons and then be out of the league.
Barry Sanders - Another great, he had 4 seasons over 330 carries and another 3 seasons over 300 carries. Oh yea and he'd only miss 7 games in 10 years.
Emmitt Smith - yet another great, he had 6 straight seasons over 335 carries and 8 seasons out of 9.
Thurman Thomas - 4 straight seasons with over 340 carries and over 300 carries 6 seasons out of 7 years.
Natrone Means - after a 400 carry season in his 2nd year (1994) he would never again play a full season or top 244 carries.
Chris Warren - he had one year with 333 carries in 1994 (4th season) and would have 310 carries the following year but wouldn't top 203 carries again in the next six seasons.
Terry Allen - had back to back seasons with 338 and 347 carries in his fourth and fifth years (95-96) but would miss twelve games over the next two seasons and wouldn't ever carry it more than 254 times again.
Errict Rhett - he had one 332 carry season in his second year (1995) but would miss 12 games over the next two seasons but wouldn't top 236 carries again.
Ricky Watters - He had 3 seasons with over 344 carries and didn't have any real drop off in the following seasons.
Jerome Bettis - he had back to back seasons with 358 and 423 carries in his 5th and 6th seasons (96-97) and would stay remarkably healthy over the next 8 seasons missing just 14 games over that time.
Jamal Anderson and Terrell Davis - these guys I'm lumping together because they both had over 470 carries in 1998 and they would both be out of the league three years later.
Eddie George - he had seven seasons with over 330 carries. He was a true workhorse.
Edgerrin James - after back to back seasons with 389 carries or more in his first two seasons he tore his ACL in his third season. He regained form though and has had another 4 seasons with at least 337 carries.
James Stewart - after a 339 carry season in his 6th season (2000) he only played two more years and wouldn't 231 carries again.
Corey Dillon - he's only had two seasons with over 340 carries and they were both well into his career (his 5th and 8th season).
LT - he's already had five seasons, out of six (not counting this year), in which he topped 339 carries and three in which he topped 370.
Stephen Davis - he had four seasons over 330 carries but was injured nearly ever other year.
Deuce McAllister - he's had one year with over 350 carries, his 3rd (2003), but has bounced back and forth between injuries since.
Travis Henry - had back to back seasons with 325 and 331 carries in his second and third seasons (02-03) but then lost his job so he's a hard guy to judge.
Ahman Green - has missed 14 games over the three years since a 403 carry season in 2003.
Tiki Barber - had back to back 370 and 353 carry seasons (05-06) before retiring, although he was showing no signs of slowing down.
Clinton Portis - had back to back seasons of 343 and 385 carries in his 3rd and 4th seasons (04-05) before several injuries limited him to 8 games in 06.
Jamal Lewis - after a 412 carry season his rookie year (2000) he missed all of the 2001 season after sustaining a preseason knee injury. Then after a 401 carry season in 2003 he missed four games and his yard per carry average fell by 1.0 in the 2004 season.
Curtis Martin - another model of health, he had 6 seasons with at least 349 carries and another two seasons with at least 300, not bad out of 11 seasons.
Shaun Alexander - after three straight seasons with over 346 carries, including a 430 carry season last year, he missed 6 games in 2006 and only averaged 3.6 yards per carry.
Sorry b/c that was incredibly long and I won't waste everyone time trying to wrap up. But those are the facts behind this 'theory' though so take it for what it's worth. Nothing is absolute but I feel like there is some correlation between a high number of carries (upper 300's) some detriment to a running back's career.