I’m clueless about professional sports, but my sources tell me that except for the undecided (again) Brett Favre, the nucleus of the Vikings team should stay pretty much intact next year.

That's very good news for Vikings fans — at least, according to a recent European study, described earlier this month in Miller-McCune magazine, on the impact of player stability on team performance.

The study (which is unpublished and which I could locate only in this HTML version) found that among professional soccer teams in two major European leagues (the English Premier League and Italy’s Serie A), those with the most stable roster of players performed much better over a period of nine years than rival teams with the highest player turnover.

The findings held up even when the researchers controlled for such variables as club wealth, past team performance and player age.

“Everyone wants to sign the big-name stars, the top players,” Mark Van Vugt, PhD, the study’s lead author and a psychology professor at VU University Amsterdam in the Netherlands, told Miller-McCune magazine. “But change does not come without risk. It seems intuitive, but now we know that team stability is a very important predictor of success in sports.”

Benefits: team coordination and motivation
How, exactly, does team stability help? Again, the answer seems intuitive (even if team owners frequently ignore it):

“In [soccer] (and presumably in other highly interactive team sports),” wrote Van Vugt in his study, “the task of winning matches is so complex that there is no rule book depicting every possible situation and instruction of what to do. The only way for teams to improve is by training and playing together so that they can perfectly synchronize their activities on the field.”

There are also some motivational advantages to team stability. “To weigh team interests above personal interests requires that people adopt a long-term perspective on their team membership,” Van Vugt wrote. Laboratory studies have shown, he added, that once teams of people realize they are breaking up, loyalty and cohesiveness begin to crumble.

What about the coach?
So, bringing in new people to “shake up” a sports team or to add new talent may not be the best strategy after all.

That goes for sacking the coach as well as for trading the players. Van Vugt’s study found that manager stability, like player stability, has a positive, although weaker, effect on team performance.

“The positive association between manager stability and team performance “is remarkable because common wisdom suggests that teams change managers when things are not going well,” Van Vugt wrote. “Due to the ‘law of averages,’ teams should normally be expected to do better after a managerial change, regardless of the quality of the new management. Yet, our data suggest that a management change reinforces a downward spiral with teams in the long-run doing even worse than before.”

Not just on the sports field?
In an e-mail I received from Van Vugt early this morning, he said the results of his study "are certainly applicable to other team sports, especially those sports that require much coordination between players, such as basketball and volleyball. Not so much to sports that require less team interaction, such as baseball and obviously golf (the Ryder cup) or tennis (the Davis cup)."

His e-mail failed to mention American football, but that sport would seem to fall into the "requires coordination between players" category.

But even if you're not a heartbroken Vikings fan, this study offers something to think about.  For it suggests that fostering stability in other “teams” of people — in the workplace, classroom, or community, for example — may also produce better results when the “rosters” are kept stable.

And, indeed, Van Vugt cites another study involving an entirely different kind of team — musical string quartets. That research, he says, found that quartets with the least turnover of members tend to sell more CDs and attract larger audiences at live performances than those who tend to change their members.

So, take heart, Vikings fans. There’s always next year, as they (annoyingly) say. We'll just have to hope that Favre returns — or, at least, that most of the Vikings' roster stays intact.