Continuity mistake: At the bowling alley after Jim bowls and walks back to the group and talks to them, we see a young man in the background with a grey top about to bowl. Then there is a quick shot that cuts to Adam and, then the shot cuts back to Jim and the guy in the background is about to bowl again.
Continuity mistake: When Martin gets covered in ketchup the position is constantly changing. (00:02:00)
Answer: It's not explained fully, but its shown that he is quite sick as he has been taking many dollops and that they were liquid (sorry for the graphic description but its explained in the show). Given those circumstances we can safely assume that Wilson has got some severe problems.
Ssiscool ★