How Will Prince Fielder Age?

While the upcoming Free Agent crop isn’t the deepest in recent memory, there are a few sexy names at the top of the list. One of those names is of course Milwaukee Brewers first baseman Prince Fielder. Looking at his stats, we see a player who has accumulated 15.3 WAR over the last three seasons and is a perennial threat to launch 40 home runs and get on base over 40% of the time. However, due to his less than slim body type, it is not prudent to assume that he will age like most other Major League players.

In order to attempt to predict what Fielder will do over the life of his next contract, we should compare him to players with similar body types. Jeff Zimmerman has put together a list of 205 players who weigh more than 3.25 lbs per inch of height in order to construct an aging curve. To put that in perspective, a 6’0″ tall player would have to weigh a minimum of 234 lbs in order to be included in the sample.

Below is a graph that shows the aging curve of the heavy players we identified, and the curve for average sized players. Across the x-axis is age, and the y-axis runs (batting, positional, UZR), with 0 being the peak year. The y-axis shows how many runs below the peak year they are at a given age.

Two things immediately jump out from this graph:

1)   Heavy players peak a few years earlier than average players

2)   Heavy players fall off the map once they are on the wrong side of 30

The second piece of information is what is of interest to us regarding Fielder. As a 27 year-old free agent he has passed his peak years according to this curve – what we want to know is how is he going to perform over the life of his next contract.

We can play around with different numbers of years on the contract, but let’s start with 7 as that seems to be the magic number recently (Sabathia, Zito, Werth, Wells).

I have put together four tables that chart expected performance based on the two aging curves. In the top two, the chart on the left models a 27 year-old average player, while the chart on the right is a 27 year-old heavy player. Both players are considered to have true talent levels of 5.5 WAR at age 27, which was Fielder’s WAR total last season. The bottom two tables are for those of you who feel that Fielder played above his true talent level last year and in reality is a 4.5 win player. Considering his age 27 season was the second best of his career and doesn’t fit the curve very well, this is a prudent assumption. For all tables, I assumed $5 million per win in 2012, and 5% inflation thereafter.

According to these aging curves, to treat Prince like an average player would cost a team over $17 million on a 7-year deal. This may not seem like a huge amount relative to the Major League payroll, but I am sure every Amateur or Latin Scouting Director would love to have that amount added to their budget.

As we can see from these two charts, the major disparity in value occurs in the last two years of the contract when the heavy player regresses badly in his early 30’s. Given this information, it would be prudent to try and sign Fielder to a 5-year deal. Unfortunately, that is generally not the way the market operates, as most General Managers can’t plan to be around seven years from now, and are more concerned with production in the immediate future. There is no denying that Fielder would boost almost any teams offence over the next several seasons.

Another factor to consider is defense. Fielder’s UZR numbers are already well below average (-36.4 runs in his six full seasons), and it is entirely possible that he could be a full-time DH before he turns 30. Locking a big money player into the DH spot can severely cripple a franchises financial and roster flexibility.

One thing we should note, and is often the case when dealing with comparable players, is that you can run into sample size issues. As you can probably tell by looking at the curve, we do run into this problem at the older ages of the heavy player curve. The fact that production actually increases from age 30 to 31 is counter-intuitive, and is due to a couple of big seasons throwing off the curve. However, the fact that the size of our sample erodes to this extent shows that a significant percentage of heavy players lose enough skill that they are no longer MLB calibre players. Because Prince is good enough that he has a lot of talent to lose before he becomes a replacement level player, there is not the risk of him immediately bottoming out, but this overall deterioration of skill among heavy players is worrisome.

While the data isn’t perfect, I think it is safe to say that signing Fielder to a Mark Teixeira contract (8/180) would be an incredibly risky move, especially considering some of the worst case projections have him providing only $122 million in value. While this figure only encompasses seven years of playing time, he will probably have decayed to the point where he would barely be above replacement level in year 8. Only time will tell if he continues to be productive into his 30’s like David Ortiz and Jim Thome, or collapses like Mo Vaughn and Adan Dunn.  Either way, it is clear that his best days are behind him. Unless I am running a team that is a serious World Series contender over the next three seasons (flags fly forever), I am extremely reluctant to hand over the contract that Fielder and his agent Scott Boras are going to want.

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85 Responses to “How Will Prince Fielder Age?”

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  1. Kyle Lobner says:

    “Either way, it is clear that his best days are behind him.”

    That’s pretty clearly false. At best, you could maybe say that Fielder’s best days could be behind him. But you’re talking about a guy who’s missed one game in the last three years. Regardless of what happens next, I don’t think there’s any evidence to support the notion that he’s certain to start declining now.

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    • drt says:

      Pretty much what this showed me is people here expect him to fall off a cliff in about a year and a half just because he is fat.

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    • “I don’t think there’s any evidence to support the notion that he’s certain to start declining now.”

      You should try rereading the article, because that seemed to be all the evidence he was showing.

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      • WilsonC says:

        The best you could say is that the data supports the idea that teams are perhaps right to be wary of his weight, as it could lead to a sharper decline than the average player. He’s comparing an individual to an average; that can tell us something about the risk he carries, but it can’t tell us conclusively how the individual player will age. In Fielder’s case, he’s an extremely durable player, coming off a peak-type season who’s shown no signs of decline. It’s silly to assume that he’s already in decline based on the average of a group of players who share a single trait with Fielder.

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      • Abreutime says:

        According to the same logic, any player has had his best days behind him by the age of 27. It’s obviously not going to hold true in a large number of cases. Certainty is FAR from established by a line graph showing averages.

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      • Hank says:

        Once again people are using an aggregate and applying it to an individual circumstance with certainty.

        It would be one thing to say “I’d expect Prince Fielders best days to be behind”, it is a whole different ball of wax to say “Either way, it is clear that his best days are behind him.”

        What this would entail would be not simply looking at the aggregate but looking at every individual case and seeing if all of them declined as the aggregate curve did. It’s the same thing with lineup protection is myth, pitching to score is a myth, etc… on aggregate it might show no/little effect, but it doesn’t mean it holds for every player and every situation.

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      • adr3 says:

        You also have to consider the fact that the Brewers were reported to be stealing signs when at Miller Park. I for one, am predicting a decline once he doesn’t know when a fastball is coming. He slugged about 200 points higher at home this season, and he hadn’t had those kind of splits over the rest of his career….

        I honestly don’t know if they were stealing signs or not, but he should regress somewhat if he leaves that park for a different one regardless of the reasoning behind his awesome numbers there.

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    • DavidCEisen says:

      If this article was turned in as a Freshman statistics 101 paper, it would probably get a B-.

      At least the team that signs him can be certain his performance will have a small increase after his 29-30 season!

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  2. oldjacket says:

    No fatties

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  3. drt says:

    Also with the best years behind him, it must have been strange for him to have his second best year just this year.

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    • Yirmiyahu says:

      Actually, if his 2011 was the 2nd best year of his career, isn’t it more likely that his best years are behind him? The 2011 season is now in the past. Unless for some reason you expect him to get better from here on out then, yes, his best years are in the past. That doesn’t mean that he’s not an excellent player now, or that he’ll suddenly be mediocre.

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      • AJS says:

        I don’t think that’s the correct interpretation, Yirmiyahu. If you look at the curve, it shows that a heavy player’s age 26-27 season is, on average, his fifth-best year. So if Fielder had his second-best year in that season, perhaps it shows he’s at least something of an outlier from the curve.

        Prince could post better numbers next season – although I’ll admit they’re only likely to be slightly better. But It’s not unheard of for players to post their best years in their age 27-28 seasons (Jacoby Ellsbury this season, Ben Zobrist in 2009; Chase Utley was 29 in 2008, etc.).

        Plus, I’ll grant that Prince is quite heavy by any measure, but is there any particular logic to choosing 3.25 lbs per inch of height as the cutoff? That seems arbitrary. Why not use BMI or make up any other test for “heaviness”?

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      • Careless says:

        AJS: BMI is just a weight per inch calculation anyway, they just chose a value that makes for a weight slightly into the “obese” category. Which is still a silly thing to do when talking about athletes, who pretty much all calculate as overweight/obese because BMI just doesn’t work for tall, muscular people.

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  4. delv says:

    time for Prince to go all out and switch from vegetarian to vegan

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    • Well-Beered Englishman says:

      I once knew a girl who coped with veganism by eating nothing but chips, or, as your nation calls them, french fries.

      Needless to say I did not know her biblically.

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      • Yirmiyahu says:

        That is a diet I would gladly sign up for, particularly if we’re not talking about thin little McDonalds french fries.

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      • Dizzy Valance says:

        McDonalds fries contain trace elements of animal products (beef) for flavoring purposes.

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  5. swieker says:

    Is the causation here just assumed: Fat caused the steeper decline? Does this study attempt to control for even a single other variable?

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    • delv says:

      Fat wasnt even the variable—it was weight. And, of course, muscle weighs more per unit of volume than fat.

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      • John says:

        This isn’t football though. I’d say most baseball players who are 6’0, 234 or 6’3 245 generally aren’t “muscular” and probably have above average body fat percentages.

        Another issue with this analysis is guys lying about their weight in their roster pages. There might be guys who, looking at them and assuming their true weight, would meet the criteria but get missed.

        David Ortiz is listed as 6’4, 230. There is no way that is true. I’m about 6’3 230 and he is much larger than me. Let alone the fact that despite having a gut, he has muscle too.

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  6. madisomoose says:

    Ryan–Do you see any differing effects from this trend of fatties vs averagies over time? It’s pretty clear that there are different conditioning regimes for everybody in the league than there were 20/30/50 years ago. I’m just wondering if a subset of people over the last twenty years follow the same trend? After all, we’re talking about somebody who at the age of 25 DID go veg in an attempt to control his weight…a far cry from a pack a day (of cigs and hot dogs) for some of the heavy sluggers in the past.

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    • Good question. I did not look at the data that closely because I feel that it is making too many inferences. For example, Mo Vaughn obviously had access to better nutritional information and workout regimens than Babe Ruth. However, that doesn’t mean he actually used them. You start to get into muddy waters when you assume that a player acted a certain way just because of the era he played in. In Fielder’s case, it does appear that he has made a conscious decision to watch his weight and take care of himself, so that is a plus. There are definitely heavy guys, regardless the era, who bottomed out because they didn’t take care of themselves.

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  7. SeaWolf says:

    I wonder the what the result would be if you charted the aging curves of elite non-heavy players vs. elite heavy players. Isn’t it generally believed that regular aging curves do not fit the known aging of elite players? If that’s the case, then we may get a different picture then what the chart currently shows.

    Also, a different aging curve for elite heavy players vs. all heavy players might explain the uptick at the age 30 season in the graph above as the non-elite heavy players are being bumped from the game, while the elite heavy players are still playing and contributing well.

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    • Our sample already gets small enough in the latter years without separating the heavy players into further sub-sets. In theory it’s a good idea, but I think our sample would get too small to draw any legitimate conclusions.

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      • Paul says:

        The sample is already too small to draw any legitimate conclusions. Plus, where does a 200 player sample come from? Historical players selected at random?

        Is this a sub-set of the peak year analysis Tango, et al. did a few years ago? The peak year looks even younger than theirs in that revised analysis to Bradbury’s, which took out all the cup of coffee guys. I strongly agree with Bradbury’s approach, btw, and Tango, et al. acknowledged there are some problems with their approach despite favoring it over Bradbury’s.

        Now here we are using some unknown sub-sample of some peak year analysis without acknowledging what method was used or that there is disagreement on methodology. Bradbury’s approach clearly was not used, which means that it is likely your small sample size problem is going to be dramatically exacerbated by including AAAA players, who tend to be corner outfielders, catchers, and 1Bmen, all fatter. Fail.

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      • Jeff Zimmerman says:

        It was the same analysis Tango used. I got the method from him. Here is the methodology I used:

        No where did Tango or MGL mention that Bradbury’s method was better. It had huge survivor issues.

        It is weighted by PA, so it will minimize the AAAA players.

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      • Paul says:

        “Tango, et al. acknowledged there are some problems with their approach despite favoring it over Bradbury’s.”

        Perhaps you didn’t read the part where they acknowledged that neither method is “correct,” but that they “believe” theirs is more correct. I disagree. It merely trades one bias for another.

        And using their method and selecting for some unknown sample of 200 players will exacerbate the AAAA effect despite the weights. I’ll take the survivor bias issues over some arbitrary weights that may or may not actually exacerbate the AAAA problem with such a small sample.

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    • Ender says:

      I remember reading a study that showed players who are elite at a young age peak for a longer time and regress later than average. I would think this would still apply to heavier players as well. I think the real key to Fielder is the defense which makes him a lot less valuable than people tend to think he is.

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  8. Hurtlocker says:

    Shouldn’t this mimic real life?? Just because he is a baseball player doesn’t negate the clear fact that extra weight causes more stress on the body, especially after age 30.

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  9. maqman says:

    His father started to go down hill in his age 30 season. Boras will get him a big, long contract, which more than likely he will not produce enough WAR to justify the investment.

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  10. bluejaysstatsgeek says:

    I agree with this analysis, but I’ll admit being biased, because this is what I’ve suspected all along. Over at Bluebirdbanter, there’s a bunch of Jay’s fans salivating over the possibility of signing Fielder, more than Prince himself would salivate over a tofu burger. I’ve been arguing he won’t age well and there is no way I’d bid for him, given what the competing offers are likely to be.

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  11. hunterfan says:

    I don’t get the people who are saying Fielder is somehow healthy because he switched to vegetarianism. People who are vegetarian can eat unhealthfully too, ya know.

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  12. DirtyDisa says:

    “Either way, it is clear that his best days are behind him.”

    I deinately disagree. This statement is not accurate at all. It is an excellent article, and it presents extremely valuable information. With that said, the “evidence” presented is showing an average. Odds are, Fielder’s best days are behind him. Unless you can show a breakdown that every single hitter of Fielder’s type saw a dropoff, that line is completely invalid. Given that exceptions to the rule, such as Ortiz, are given in the article, I am not sure how this claim is backed up. The sentence could be re-worded.

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  13. DirtyDisa says:

    Yea, I agree Hunterfan. If I remember correctly, Prince didn’t become a vegetarian for his health. I believe his wife showed him an animal cruelty video. I read that in a Prince interview years ago, so that could be off.

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  14. Flharfh says:

    I think there is something to be said for the fact that Fielder seems to be naturally that size, instead of simply failing at nutrition / conditioning and getting fat and out of shape like some players do.

    Fielder’s already poor defense coupled with his aging is a big concern, but it would be for a thin but poor defender as well. I would feel a lot better giving him 6 years as an AL team. Huge crap shoot if he has to play defense; it could get so bad that it would negate a lot of value.

    Also, how do this analysis account for players who may have crossed into or out of your sample size during their careers? For example, a player who gains enough weight to put him into the group halfway through his career, or one who loses a enough to leave the group, or a borderline case where fluctuations could put them into or out of the sample on a year by year basis?

    Also, shouldn’t there be more of a distinction between “big” (muscular) players and players that are simply “fat”?

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  15. philosofool says:

    I’m not sure I buy the aging curve. What I want to see is if you take all fat guys in year n and look at their year n-1, what’s the difference, on average. Otherwise you get a sampling problem, namely, that since there are vastly more skinny/normal dudes, the ones who fell off a cliff in year n-1 aren’t in n and the rest of the guys wash out the average to make the changes look small.

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    • Paul says:

      Agree. But it goes even further. We have no idea what the sample parameters are and it’s only 200. The only way that’s not incredibly small is if you used only HOFers. Not to mention where the height and weight data came from, as we know that it is not exactly accurate. We have seen a trend just in the past few years of players losing huge amounts of weight in the offseason. In the steroid era we saw the opposite. I.e., enormous bias issues.

      On some local blog somewhere this would never be questioned, but analysis with all these problems should not be published on FG in order to argue that one of the best hitters in his generation is washed up simply because he’s fat.

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      • Not sure where you inferred washed-up from. The worst case scenario I projected is still $122 million dollars in value, which is a pretty darn good player. The point is that you are assuming a lot more risk in years 5,6,7 than you would with most other players.

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      • Paul says:

        You are assuming more risk in later years than with mediocre players. I’ll stop complaining if you run the analysis using Bradbury. If you think it’s wrong, say so and why. But why not put them side by side?

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    • Jeff Zimmerman says:

      The n and n-1 method was used. Here is how the data was calculated:

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  16. k says:

    I would guess that “heavier players” are more likely to be moved to easier positions as they age. It would be more useful, then, to compare just players that started as 1Bs because they’re less likely to take a positional value hit, right?

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  17. Richie says:

    Don’t remember where I read/heard it, but I thought Prince had given up the vegetarianism thing.

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  18. Dudley says:

    are you sure the difference is statistically significant? i’m skeptical.

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  19. Dudley says:

    what is the coefficient for the “heavy” dummy variable? what’s the MSE? seems like a few outliers could’ve skewed the data.

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  20. Shawn says:

    Actually, Fielder has not been a vegetarian for some time. It has been reported on elsewhere.

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  21. Keystone Heavy says:

    Rarely do i smh at fangraphs. He should be paid just as much as a skinny player with the same production. Workplace discrimination is not cool!

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    • joser says:

      It’s his future production that’s at question, and whether his weight will cause him to produce less than an equivalent thin(ner) player (and therefore should be paid proportionately).

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  22. bluejaysstatsgeek says:

    At Fielder’s height of 5’11”, he would have to be 231 pounds to qualify for the “heavy” group, based on 3.25/inch. FG lists his weight at 268 and BR lists him at 275, and I wouldn’t be surprised if both were low. I wonder what the aging curve would look like with a cutoff closer to Prince’s 3.77? Also as one person has pointed out, muscle is more dense than fat, there’s no doubt that a lot of the weight that he carries is fat.

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  23. Billy Beane says:

    Prince Fielder is too fat, even for my team!

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  24. Hank says:

    Ryan, how was the weight screening done? (in evaluating average vs fat)

    Did you consistently evaluate this year to year if a guy got into or fell out of shape? Did you just look at weight/height at a specific age and assume the body type was consistent over the career? Or at the start (or end) of the career, independent of age?

    Also, perhaps a minor point, but is the weight data accurate? Not sure where Jeff pulled it from, but sometimes the published data can be “massaged” by teams… (though this is probably more likely with overweight players so it may be less of an impact)

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    • Jeff Zimmerman says:

      I was the data for the player listed in the FG dataset. I expect the weight numbers are low.

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  25. Mayor McFleas says:,4613

    If I was a GM looking at signing Fielder to a long-term deal, that bottom graph would scare me plenty.

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  26. RobBob says:

    I can’t buy into the conclusion that since other big guys, on average, have done such and such, then Fielder is destined to the same fate. First of all, the Prince’s profile looks *nothing* like the average profile shown here for big players. In particular, Prince has not been steadily declining since his age-23 year, he’s been steadily getting better. If you are going to make some claim about what Prince may or may not do, you should at least compare him to other players that have had the same trends as he has through his age-27 year.

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  27. Scooby Doo says:

    Ok, so who do I start planning as my replacement for Prince on my dynasty fantasy team?

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  28. Vincent says:

    C.C. Sebathia

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  29. Bill says:

    One problem with this study, roster weights are rarely accurate. I remember when I was 18, I’d lie and write down 200. Then when I was 25, I’d lie the other way, and say 210. LOL!

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  30. jcalton says:

    I realize we don’t have any alternative, but bear in mind that they lie about height and weight in the media guides (or on baseball cards) all the time.

    I’m not saying Fielder’s not fat–obviously–I’m just saying that certain criteria such as height to weight ratios will be subject to data manipulation outside our control.

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    • A very valid concern. If I had the time and resources to go and measure and weigh every MLB player ever I would, but unfortunately that’s just not realistic and we do our best with the data we have. I should have noted this in the article, thanks for brining it up.

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  31. John says:

    I didn’t scroll down to your post jcalton before posting mine.

    There are guys like Ortiz who are clearly lying about their weight in the roster guides and get missed in this analysis (although Ortiz is a guy who would likely buck this aging curve ironically, although (alleged) PED use muddles that)

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  32. jirish says:

    Prince is fat. He’s been fat his entire life, even as a child. He’s to date never spent a DAY on the disabled list-majors or minors. He doesn’t ever miss games for nagging injuries, illness, or personal problems. He plays almost every inning of every game and has done so for years. Prince isn’t like other players. He’s named Prince-that’s royalty. He has the most dynamic left handed power swing I’ve seen in my lifetime.

    Prince isn’t going to fit neatly into any graph. He’s already an outlier. I predict he remains one. He can play on my fantasy team and I hope my favorite team signs him-long term, if necessary.

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  33. WilsonC says:

    How does weight correlate with traits other than WAR?

    For instance, if players who spend time on the DL when they’re young tend to fall off sooner, and large players tend to be injured more, that could explain the numbers shown by the graphs, yet Fielder’s been extremely durable so that could muddy the results. Or, strikeout rates – Fielder makes better contact than a lot of mammoth sluggers like Dunn or Vaughn – does his better contact rate move him out of the “old player skills” classification?

    There’s really several possibilities: weight could directly cause many players to decline more sharply, or weight could indirectly cause some players to decline sooner by affecting some peripheral factors (such as durability), or players who share a peripheral trait (such as high-K rates or poor speed) may be more likely to be large.

    Fielder’s big, but he’s not defined by his size; it’s just one of many traits he has, and it doesn’t negate the need to look deeper to properly assess the comparative risk of Fielder versus other players.

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    • There is definitely more than one way to analyze what Fielder will do. I am sure as the off-season progresses we will post more articles. We try to keep our articles concise and to the point, so this was just a look at one factor of the entire Prince Fielder puzzle.

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  34. the real neal says:

    About 10 years ago some Ivy Leaugue school released a study that said 85% of NFL players were obeses as measured by BMI (height/weight). This article involved more math, but was logically just as flawed.

    According to Ryan Campbell, Arnold Schwarzeneger and Boomer Wells were equaly fit people.

    Unless you know the muscle and bone mass vs the fat mass, you don’t really have anything to study…unless we can all agre that Herschel Walker had 2% body fat and was obese.

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    • Thankfully this isn’t football. Yes BMI and height/weight ratios don’t work in football because you would be comparing running backs and their tree trunk muscular thighs to offensive lineman and their guts.

      This is baseball. How many baseball players look like Arnold or Herschel Walker? The only player that really jumps out to me from the list that might not fit is Carlos Delgado.

      Here is a list of recent players whose names I quickly recognized. None of these guys have “2% body fat”. And there was a ton of guys who I am assuming are old-timers and whose names were “Tub” and “Jumbo”. I have no idea who they are but I’m guessing they aren’t the pinacle of personal fitness.
      Toby Hall
      Andres Galarraga
      Humberto Quintero
      Bucky Jacobsen
      Bengie Molina
      Carlos Lee
      Randy Ruiz
      Adam Dunn
      Wily Mo Pena
      Randall Simon
      Dmitri Young
      Mo Vaughn

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      • The Real Neal says:

        We’re talking about Fielder’s Body Fat, not Carlos Lee’s, though? That’s the point I was making. Fielder probably has a lot higher muscle/fat ratio than the average player on your list.

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      • ray says:

        and most don;t compare to Fielder in terms of production.

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      • Harlock says:

        Well, Bucky Jacobsen wasn’t fat, I remember that. Dude was built like a 19th century lumberjack. Too bad he got injured: he hit some mammoth shots for the M’s in his 1/2 season.

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  35. Joey B says:

    Great article. I’m not sure why so many people are hung up on the phrase ‘his best days are definitely behind him’. It’s incorrect, but I think the readers should assume nothing in the future is ‘definite’, and figure out that the author meant statistically likely’.

    Beyond that, I’d have two questions-

    1-Can the WAR declines be segregated by position? Someone like CLee is going to lose an awful lot of defensive WAR when he plods through LF, not to mention the stress on the body. Someone at 1st might not lose nearly the same range, especially if he is quicker than he is fast, nor will the body stress be as high.

    2-Is there a way to ‘value-in’ the difference between the AL and NL? It just seems like there should be a difference. If the RS want, they can slide Youk into DH and not gut his value. The Astros only choice is to trade CLee and eat a huge chunk of salary. I assume the decline in WAR is due to positional deficiencies that might not play out the same in the NL and AL.

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  36. ValueArb says:

    “At best, you could maybe say that Fielder’s best days could be behind him. But you’re talking about a guy who’s missed one game in the last three years. Regardless of what happens next, I don’t think there’s any evidence to support the notion that he’s certain to start declining now.”

    You understand the argument you are making here supports the idea Fielder is due for a decline. Few players miss only one game in three years even in their prime, adjust his WAR numbers for averaging 150 games or even less and that’s a decline in total value even if his rate stats remain unchanged.

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  37. kick me in the GO NATS says:

    Fielder could easily be the exception to the rule here, like Babe Ruth. For one thing he is far from the typical heavy guy as he is a vegetarian. I doubt many if any other fat guys were or are vegis. Perhaps eating ones vegis will make him more durable. But regardless, he may have a greater probability to decline because of his weight, but that decline is far from guarranteed. You could bet he becomes Babe Ruth as easily as Mo Vaughn.

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  38. CircleChange11 says:

    We all realize that Prince Fielder and Cecil Fielder have different skills right?

    Heck, if you go by the metrics here, CF was a better fielder than PF. Who woulda guessed that?

    CF had 2 seasons where his batting run value was greater than 20. PF has had 3 straight. CF had season over 50 Batting runs, PF has had 3.

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  39. PHILLY JIM says:

    interesting read. i think the unknown here is how will Fielder take care of his body over these next few years? You saw Ryan Howard lose weight and work on this defense and the Phils rewarded him partially on that. though i think I’d still rather give Prince a 7 year deal than have the older Howard for the next 5, and that was before Howards injury. What concerns me is that while Prince has a big year in this his “job interview” year, i would have been more impressed if he had really done something to get his body in better shape and give me more confidence he’ll hold up better when he gets into his 30’s.

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  40. Dan Greer says:

    It’s nice to see the “aging curve” to back up what people have said all along, but I’m skeptical about a couple of things regarding this study.

    First off, it’s not at all clear that Fielder has shown a single sign of decline yet, which the curve suggests on average, he should have. Second, I’d be curious to know what the statistical reason for the decline tends to be for the heavy players, and compare that to the normal population. One thing you do include is the positional adjustment, and yeah, heavier players tend to work their way toward 1B or DH, if they don’t already start there.

    Fielder’s UZR and BRR, while poor, have remained steady; while his ISO has bounced around a bit, nothing seems amiss. I’d have to guess that much of the projected decline would stem from a combination of normal aging and small losses of bat speed, which should lead to worsening contact rates and increased ground ball rates. Prince just posted a career-best contact rate, which I believe bodes very well for his immediate future, though he is hitting fewer fly balls than before (which is bad).

    His body type is just one thing to focus on, and it’s certainly possible that he remains healthy and productive for years to come. I wouldn’t say that either is very likely past his early to mid 30s, but I would say that of any Major League player. As long as he keeps his contact rate up and continues to hit the ball very, very hard, there doesn’t seem to be much to worry about.

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  41. baycomuter says:

    Pitchers are going to be different. Cy Young was fat as hell and pitched to 44. He was still throwing OK at that age, but he was such a tub they literally (and cruelly) bunted him out of the league.

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  42. The Real Neal says:

    Just caught this one:

    “Either way, it is clear that his best days are behind him. ”

    No, it’s not. It’s clear that the average player in your study had his best years behind him. There’s not a single person in baseball who would be shocked if Fielder has his best year next year.

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  43. evo34 says:

    Nice article. Unbelievable the random excuses people have made up in the comments. The data speaks for itself. If Fielder had had even a slightly down year, people would be clamoring to bury him. Yet because he happened to have a nice year, he is the exception to what the data shows. Right…

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  44. Antonio Bananas says:

    The number of players who have multiple great years is small. The number of players who have lengthy primes is small. The number of players who decline (in general, not on the dot) after 27 is large. The number of fatasses who don’t decline faster than average is small. Miller is a hitters park, the NL Central also has had pretty weak pitching.

    So yea, what exactly says he won’t decline? That he’s an “outlier”? The production curves of all players are similar. He may still be more productive at 35 than other fat players, or other players in general, doesn’t mean he’s going to be worth the huge contract he gets.

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  45. Justin says:

    Prince cannot field, therefore, he is already best suited to DH.

    Should he DH, or at least be allowed to do so in the near future and not have his fielding hurt his WAR then his value probably sustains well.

    We are talking about someone that is 5’11” 270lbs, that is not big, heavy, or large…that is just huge, unhealthy, and undoubtedly a risk to both his heart and his appendages. That make him one of the largest players in recent history, absolutely massive for an athlete. Most NFL lineman are around 300lbs or weigh 30lbs more and are AT LEAST 5in. taller, if not 10in.

    I think he is a 5.5 WAR player for a few seasons, likely the next four, and should safely pull in 28 WAR over the next seven seasons making a 7yr/140M a worthwhile risk, IMO. Should the team be in the AL with a DH spot open in the in the three years then something in that range would be a good move. Every signing comes with risk and what this guy is able to do is crazy good. He can walk with the best of them and is a true .300/.400/.500 guy.

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    • Jack Straw says:

      So, you’re saying Fielder is remarkably fat for a baseball player, yet he’s going to be even a little bit better than his projection next year for the next FOUR years, a period when players typically decline? How does that make sense?

      I don’t think anyone thinks that Fielder for 20m a year is going to be a bad bet, even for seven years. It’s when you get into the 25m range that a long contract starts to look unreasonable.

      I do think Fielder’s at the stage where his fielding has become a real threat to his long-term value, to the point where one more step down and his fielding makes him, in effect, a DH for the purposes of WAR, even he’s still running out to first base every inning. I’d be more convinced by the arguments in favor of Fielder resisting the inevitable over the next five years if it could be persuasively argued that fat players hold onto their value reasonably well in the field, not only at the plate. I doubt that argument can be made well.

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  46. Tigers fan says:

    Great article, it’s even better looking at the date it was written, 2011. Fast forward to 2013 ALCS, fielder has 0 RBIs his batting avg the entire post season is less than .100 and has 0 extra base hits.

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  47. Tough says:

    I think he batted .200 or somthin still terrible and maybe 1rbi. By the way his huge contract was just sent to Texas to deal with, along with $30 mil. Basically tigers Orginization saying it didn’t work out.

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