Peak performance is more readily understood in other sports. In baseball it has nudged younger recently, but still it is probably a 3 year window from 26-29. In basketball peak is probably a year younger at 25-28. For soccer there have only been rough estimates, more a guideline than a formal study. There is also some evidence that the further forward on the pitch a player plays the younger their peak. Simon Kuper recently used a small sample to show that peak for soccer players is similar to that of other sports.
Generally the offensive players are more athletic, speed based roles, while defenders and center defensive mids are more about their head. If we posit that the window for defenders is slightly older at 26-29 and for offensive players at 25-28, with keepers being 28-31 we have an estimate that passes the eye test, if not one that can be rigorously studied at this time.
This peak period is when that individual player will be at their top performance. It also happens to be when they are most likely to be perform at a high level and be underpaid, since most sports are set-up to pay for past performance not future.
While Chris Henderson said that Seattle may have to break up its team without a major trophy in our interview last week, there isn't a lot of age on the squad. Even if Mauro Rosales makes the team Seattle will only have 3 starters on the wrong side of their peak. In the attack Seattle averages 25.69 years old (with Blaise Nkufo being the old man), in defense Seattle is 26.64 while the keepers are 31 on average. Overall Seattle has nine players post peak this year. Two of them are certainly going to be done at the end of the year - Kasey Keller and Blaise Nkufo. That's a decent foundation, in fact next season, none of the peak players move to their past peak period.
But it isn't as good as a team that Steve Davis is pegging as the model on pitch club in MLS right now - Real Salt Lake. Seattle does have one more win than RSL in the past two campaigns, but the Utah club has four less losses (really the difference is CCL performances, one team had two Open Cup runs the other better in MLS Cup Playoffs). RSL has three players post-peak, and one is an MVP candidate - Javier Morales. Robbie Russell and Andy Williams both get regular time, but aren't locks for the First XI. They are built for a multi-year run even more than Seattle.
If we look at a few of the other MLS Cup contenders though they are in worse situations than Seattle. The Los Angeles Galaxy are blatantly past their peak. While their three DPs are all great players, they are all overvalued financially, and two of them are well past their prime. But the fun doesn't stop with David Beckham, Juan Pablo Angel and Landon Donovan. They have five other players who are past their peak and we're not talking role players, but players who will get time.
FC Dallas has only five guys past their peak. This time the MVP candidate that appears is David Ferreira. They too have an older keeper and some older defenders, but more like RSL their depth is young. Rounding out the contenders are the New York Red Bulls, who should probably be the Grey Bulls with 10 players on their roster past peak. First teamers, second teamers, bench warmers - the team is littered with them.
Sure, Seattle has some age on the team, particularly at Target Forward (Nkufo, Nate Jaqua, Pat Noonan) and at Fullback (Leo Gonzalez, Zach Scott). It wouldn't surprise many if two or fewer of those players were on the squad in 2012. The core is within its peak window and signed for several years. This isn't a make or break season, but instead a season to capture peak performances and simply continue to retool the 20% every off-season.