Continuity mistake: When the guys are at the bar before going to the awards show, we see Marshall raise his beer to his mouth twice from different angles, without ever lowering it. Also, the amount of beer in his glass changes instantly between the shots. (00:03:30)
Continuity mistake: When Ted is talking about getting a blessing from a pimp, Barney's drink just disappears from the table. (00:03:35)
Continuity mistake: When Ted and Marshall are watching Sandy Rivers read the paper on TV, the items besides the TV on the TV table switch according to the angle.
Answer: After running the marathon for Marshall with no training, he's allowed to ride the subway for free. While sat on the train, the muscles in his legs start to seize up after the marathon to the point it is painful to move his legs. This is why he can't move them. It's the same reason your body aches after a good session at the gym the day before.
Ssiscool ★