Instead of vast maneuver grounds and lots of instructors and equipment, soldiers can train with small but high-tech gear such as Dismounted Soldier Training System, or they can practice techniques, such as squad tactics or IED recognition, using a training game on a laptop or even smartphones.

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But there are also some 400 plaintiffs who never played a single down in a professional game, but participated in training camps or served time on a practice squad.

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