Not sure if you are referencing anything specifically but some notable ones like Revis, Holmes, Ray Lewis all have nothing to do with conditioning.
If you want to knock training staffs and conditioning than you can cite some "soft tissue" injuries like hamstring and groin pulls. I know they have increased for the Jets this year but that could very well be an anomaly. I would need to see data for the entire league to see if injuries are trending upwards.
We also forget that this league has a 100% injury rate. If you play long enough, you will get injured. Advances in medicine and nutrition have helped prolong careers.