Coach Carl Q&A

This is part of a series of posts I’m doing this spring focused on marathon training. To get these “Marathon Monday” posts in your inbox, sign-up here! 


Hey everyone — welcome to the first edition of “Coach Carl Q&A” (working title)! Today I’m looking at a couple questions related to goal pace: how to pick it and how it relates to your training. If you have a question you want answered in a future column (or a suggestion for the name for this column), I want to hear it!


Let’s get down to it:




“So let’s say hypothetically that my marathon pace is 6:30 (390 seconds–granted I know it’s not there yet!–does that mean my lactate threshold pace is between 6:19 (378 seconds) and 6:22 (382 seconds)? Did I do that math correctly?”
— Peter K.




This question references the “Marathon Training Elements” infographic that I posted a few weeks ago. In it, I included the fact that studies have shown marathon pace is approximately 2-3% slower than lactate threshold pace. To answer the second part of the question first — yes, you did the math correctly (or at least the way I would — so take that for what it’s worth!).


However, you shouldn’t be trying to calculate your lactate threshold this way. Keep these things in mind when you’re looking at this stat:


1) The stat is NOT going to be true throughout your training cycle. Until you build up the endurance necessary for the marathon, you won’t be able to maintain a pace 2-3% slower than lactate threshold over the course of a marathon. Which leads to point number two …


2) Don’t use goal marathon time to predict lactate threshold pace. Goal pace is not a good representation of your current fitness until the end of your training, and even then it depends on how well you set your goals. It’s much better to use current race performances to estimate lactate threshold pace and other markers. And, finally …


3) The most effective way to use this stat is to help predict marathon pace based off lactate threshold pace, rather than the other way around.

So why the heck did I bother to include this stat?


The main reason I included it was to emphasize just HOW MUCH endurance matters in the marathon. If you look back at the chart, you’ll see that the only training listed that is slower than lactate threshold pace are easy runs (hopefully!), medium-long runs, long runs, marathon pace runs, and technically tempo runs by a few seconds/mile if you’re doing them correctly.


Yet the marathon itself is slower than lactate threshold pace! So that means that you’ve got to do a whole lot of work in those areas to get ready for the race.


Does it mean that you should ignore the other training? Absolutely not. But I think the stat does emphasize in a very real-world way just how important aerobic development is, especially for the marathon. Like the chart says, “when in doubt, work aerobic systems.”




“When training for a PR what would you consider an ideal or realistic training goal? Example my marathon PR is 5:42:12 should I train for 5:30 or 5:35? When I ran 5:42 I felt like I could have made 5:30 but bathroom stop for upset tummy and too frequent walk breaks hindered that.”
–Angeline N.




This is a great question! We all spend a lot of time struggling with what our goal time should be. Before I get to the meat of the question, I want to throw in a quick side note:


For the majority of your training, you want to base your paces, workouts, etc. off of your current fitness rather than your goal time. Make sure that you’re not plugging your goal time into an online calculator and doing workouts based on those paces. That’s a great way to push too hard, too soon and either have ineffective training or get hurt.


Ok, soap box = off.


So how do you decide what is a realistic goal? A few things I think you want to keep in mind / ask yourself:


1) How experienced are you as a runner?
We all remember when we first started running and every race was a PR. But the steep part of your improvement curve doesn’t last forever. If you are a relatively new runner, you can assume a bigger potential drop in time than an experienced runner.


2) What do your other races say?
Race-equivalency charts are a useful (though not perfect!) tool to see if you still have room to grow at a particular distance. If your half time equates to a faster time than you’ve run in the marathon, that’s a good sign that you can aim a little higher. Don’t try to use 5k/10k times, though, as the marathon is such a different distance it’s hard to predict off anything shorter than a half marathon.


3) Can you improve/add a specific aspect of training this cycle?
Maybe for your last marathon you didn’t do any speed work. Or you’re planning to up your weekly mileage this training cycle. Or you had bad weather on race day. Or you’ve started an awesome Pilates class. The big thing here is that repeating the exact same training might allow you to improve a little bit (because of more experience and accumulated training), but making a bigger change can allow you to dream a little bigger, too.

Once you think through those questions you can start to formulate what goal time makes sense for you, based on your individual situation.


That’s it for this edition of “Coach Carl Q&A!” I’d love to hear what you think, or questions you have for future editions. Comment below, shoot me an email, or contact me on Facebook or Twitter!


About Coach Carl
Coach Carl is a USA Track & Field Level 2 endurance coach who works with runners of all ability levels to reach their goals. He has been featured in Runner’s World, Women’s Health, and Competitor and is a regular contributor to Running Times.