Most of the time, bettingline shifts mean that a lot of money is coming in on one side of the action.
American football, such as the National Football League (NFL) and college football (NCAA) is unique compared to the other do-called big four sports, like the Major League Baseball (MLB), the National Basketball Association (NBA), and the National Hockey League (NHL).
Those sports may play everyday (MLB) or three-four times a week (NBA, NHL), so there is not as much time for the betting lines to move.
That is not the case with football. Teams play once a week most of the time, with an occasional Thursday game.
Once the opening lines, like the money line, point spread (a forecast of the number of points by which a stronger team is expected to defeat a weaker one), and over/under totals (the expected total amount of points of both teams combined) are set, the lines then move according to the wagers placed by bettor.
How betting lines move depending on wagers
Here is one example of the betting line shift in American football from the 2018 NFL season. In week four, the Cincinnati Bengals traveled to face the Atlanta Falcons, and both teams’ offenses came in hot to start the campaign.
The over/under total opened at 48 points.
Bettors all over the world poured money in on the over 48, so the line moved up to 49, then 50, then finally to 51, a line shift of three points, which is pretty large in the NFL The bettors turned out to be right on the money that day, as the two teams combined for 73 points, in a 37-36 win for the Bengals.
In fact, the over of 51 was covered in the first half, with the halftime score 28-24.
Super Bowl 53 had a major line shift right after the line opened with the Los Angeles Rams as a -1 favorite.
Within days, the line had shifted to -2.5 to the New England Patriots. New England ended up winning 13-3, covering the line.