Paul Yetter Breaks Down His “Rule of Thumb” For Guesstimating IM Potential

Written By Paul Yetter, Head Senior Coach, North Baltimore Aquatic Club

A few weeks ago SwimSwam posted an article that featured a 4×200 “Add-Up” of the top 400 IMers in the history of swimming. There was a lively discussion within the comment section! The specific metrics of an 800 add up is a great way to tell if someone is ready to do a high-level 400 IM.

Since around 2004 I’ve been using a formula that takes the 800 add-up a step further. Take the add-up, divide it, and add 5-10 seconds. An athlete’s 400 IM PR should fall within that range.

I like the same formula for the add up of the 100s as it relates to the 200 IM. Take the 4×100 add up, divide it, and add 6.5-8.5 seconds. You could use 5-10 as well here but the 6.5-8.5 seems a better range and closer to congruent with the 400 formula.

Former NBAC and current UMBC swimmer Nick Poulos and I have discussed this concept many times, so after the SwimSwam article posted he went to work and plugged the formula I use into Excel.

The first page shows the names and the 4×200 of each athlete. Swipe to the second page and you’ll see the Add-up, the ranges (plus 5 and plus 10), and the athlete’s actual 400 IM time. The third page is the whole spreadsheet.

The bold red falls outside of the formula’s range. The muted red is outside of the range but only by less than a second.
The normal font falls within the 5-10 range when taking the athlete’s add up and adding 5-10 seconds.

The only thing that is somewhat fuzzy within this spreadsheet: the spreadsheet shows the athlete’s PRs for 200s- but it doesn’t show exactly when the PRs occurred compared to when the PR 400 IM occurred. For instance, Katie Hoff’s PR of 2:28 Breaststroke came after she went 4:31. I think she was a 2:30 at the time.

A few years ago I remember researching and finding that some of the best men of all-time fell within a plus 3 to plus 6 window. Quickly looking at Michael Phelps’ 200 times in 2008 – when he set what still stands as a World Record- he was closer to plus 3 – plus 6 given the 200s he was doing at the time (at the time had not put up his eventual 200 Breaststroke PR).

It’s my belief that without a goggle mishap en route to winning the 200 Fly Gold Phelps would have been faster at the time in the 200 Fly- possibly adjusting his add-up a bit.
Regardless, this formula will get you pretty close to a “best guess” on an IM time. It’s important that the 200s and 100s of a stroke are raced…you can’t just say “the athlete most-likely would do ‘x’ time in a particular 200…the idea is that they actually have to DO it. They have to RACE it.

To be great at a 400 IM, you have to be really good with your Stroke 200s. LikewIse, the 200 IM is a function of an athlete’s best 100s.

I first started thinking about this when I was in a conversation with Coach Urbanchek and Coach Bowman – they were discussing the idea of being within 5 seconds of the World Record (or was it American Record?) in each stroke 200 if you want to be a World Record Holder in the 400 IM. This conversation took place when one of Jon’s U of Michigan athlete and USA Swimming legend Tom Dolan was still the World Record Holder in the event.

What do you think? How does this formula work for you / your athletes?

Paul Yetter‘s Bio:

Paul Yetter became NBAC’s Head Senior Coach in November 2016. Prior to the Fall of 2016, Paul was the Head Coach of T2 Aquatics (Naples, FL 2010-2016), an Assistant Coach at Auburn University (Auburn, AL 2009-2010), NBAC’s Head Senior Coach (2004-2009), and NBAC’s Harford Site Lead Coach (2002-2004). During the 2001-2002 season, Paul gained experience assisting National Coach of the Year Bob Bowman with a variety of NBAC’s training groups.

A 7-time member of USA Swimming’s National Team Coaching Staff, Paul has represented the USA as an Assistant Coach at the 2008 Olympic Games, the 2007 Japan Open, the 2006 Pan Pacific Championships, and the 2005 World Championships. Additionally, Paul has served as the Head Women’s Coach of the 2007 Pan American Games, and most recently as the Head Men’s Coach for the USA’s Youth World Championship Team at the 2013 Youth World Championships in Dubai, U.E.

Coach Yetter’s athletes have represented the USA in every major International Competition, winning medals at the Olympic Games, Paralympic Games, World Championships, Pac Pacific Championships, World University Games, Pan American Games, Junior Pan Pacific Championships, and the FINA World Youth Championships.

Yetter was Katie Hoff’s coach when she set a LCM World Record in the 400 IM in 2007, and then again in 2008.

Since 2003, Yetter has guided 12 different athletes to a No. 1 US National Age Group ranking, setting over 75 US National Age Group Records in the process.

For his efforts in coaching, Yetter was named the 2007 USA Swimming Developmental Coach of the Year as well as the 2007 United States Olympic Committee Developmental Coach of the Year for all Olympic Sports.

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16 days ago

It doesn’t account for the piano of sprinters. Lol. Not typing the name. iykyk

23 days ago

I am wondering what would this estimation method tell about Ledecky’s prospects in 400IM LCM. A swimmer who has been systematically challenging this event having until last year only one of four but very strong stroke and unprecedented speed endurance in long distance events. Ledecky has plans to swim 200BU this week. I don’t know if she ever competed in 200BK and 200BR.

23 days ago

Where’s the men’s sheet?

Reply to  Bud
23 days ago

The conference’s aren’t finished

23 days ago


Last edited 23 days ago by Yozhik
24 days ago

Kate Douglass
-predicted 200 IM SCY = 1:48.15 to 1:50.15 (actual = 1:50.15)
-predicted 400 IM SCY = 3:54.80 to 3:59.80 (actual = 4:16.94 from 2016)
-predicted 200 IM LCM = 2:08.12 to 2:10.12 (actual = 2:09.04)
-predicted 400 IM LCM = 4:38.86 to 4:43.86 (actual = 4:57.66 from 2016)

Alex Walsh
-predicted 200 IM SCY = 1:50.69 to 1:52.69 (actual = 1:50.08)
-predicted 400 IM SCY = 3:47.78 to 3:52.78 (actual = 3:57.25)
-predicted 200 IM LCM = 2:08.00 to 2:10.00 (actual = 2:07.13)
-predicted 400 IM LCM = *could not find 200 FL LCM*

These are their best 100/200 times from USA Swimming. Some are from several years ago and… Read more »

Last edited 24 days ago by Swammer
24 days ago

What I get from this is that Hali Flickinger, Elizabeth Beisel, and especially Yana Klochkova were/are extremely well-conditioned athletes who swam/are swimming closest to their potential. It should come as no surprise that all three came from higher-volume programs. You can’t fake the funk in a long course 400 IM.

Mary Sophie-Harvey and Suzanna Jakabos might want to look for a new approach to their training and conditioning if they want to reach their 400 IM potential.

24 days ago

Great tool to let your swimmers know where they should be.

24 days ago

Any reason why Stephanie Rice (still the 4th fastest female 400IMer of all time) and Kirsty Coventry (5th) aren’t on this list?

Reply to  Mark
24 days ago

because you can’t find times for them in all four stroke 200’s which is also why eg Kaylee Mckeown isn’t on the list either

Reply to  flicker
24 days ago

Of course – after searching for a while I literally can’t find that either of the two ladies I mentioned ever swum a competitive 200 breast.