this piece was sent to us by Frank Cooney of The Sports Xchange
, best known among CHFF readers for his singular vote for Brett Favre as the NFL's 2007 MVP. The piece is reprinted here with his permission.)
By Frank Cooney
Changes in procedure and equipment are being cited as possible explanations for conspicuous changes in vertical jump results at February's National Invitational Camp at Indianapolis, NFLDraftScout.com
Numerous teams questioned the results at this year's Combine, where the average vertical jump of more than 300 players was only 29.9 inches, compared to an average of 33.2 inches over the previous nine years based on unofficial data kept by NFLDraftScout.com.
"I don't believe in coincidences, so the changes in results are probably attributable to a new method and a new machine," said one NFL general manager.
A representative of National Football Scouting, which runs the Combine, confirmed those changes but declined to further comment.
Most NFL teams have reconciled the data and are able to make necessary evaluations for their own use. However, officials at National Scouting have sent a memo to all teams, saying "We are continuing to research the circumstances surrounding the results and will update everyone as soon as we have finished this investigation."
The vertical jump is considered an important measurement by many NFL scouts who believe it best demonstrates a player's natural ability to make an explosive move. So the lower numbers at the Combine this year were an immediate concern by many coaches and scouts.
Curiosity was further aroused when players showed significant increases in the vertical jumps at their Pro Day workouts compared to those at Indianapolis. In a sampling of 20 players, there was an average increase of more than five inches at the Pro Day drills.
However, results of Pro Day data should be devalued relative to those at the Combine, where the environment is the same for all athletes and professionals from National Scouting strictly enforce procedures in all events to assure consistency.
Ironically, it is that desire to assure consistent, reliable results which may have led to the notable changes in vertical jump results over the past two years. And NFL teams themselves may have precipitated the change.
Starting last year, the pre-jump measurement -- which determines the baseline from which to calculate the vertical jump -- was changed from a two-hand reach to a one-hand reach against a wall. The change was made to comply with the results of a consensus vote of NFL teams.
Logically, a one-hand reach should establish a higher baseline and therefore diminish the difference between that and the highest point of the jump. Raising two arms simultaneously almost always results in a lower reach. The two-hand measurement was done into the Vertec machine, which is specifically designed for this event.
Also, a new Vertec machine was used this year because the old one was "on its last legs," according to one report.
So, with that new procedure in place last year and a new machine added this year, it would be inappropriate to compare vertical jump results from either of the last two years to any previous combine.
However, when that change was made in 2007, there was only a slight change in results compared to previous years. Unofficially, the average vertical jump last year was 32.9 inches compared to 33.2 the previous eight years.
But the questions really began this year, when the average fell below 30 inches. The most obvious answer, in addition to the new method, was that that this year a new Vertec machine was used.
Annual Combine Vertical Jump results*
Year -- Avg.
1999 -- 32.3
2000 -- 32.5
2001 -- 34.4
2002 -- 33.6
2003 -- 32.8
2004 -- 32.6
2005 -- 34.0
2006 -- 34.0
2007 -- 32.9
2008 -- 29.9