Q&A: Pacing for your marathon goals

This is part of a series of posts I’m doing focused on marathon training. To get “The .2” posts in your inbox, sign-up here!


Welcome to another edition of Coach Carl Q&A (submit your questions here). Let’s get to it!



I’ve been training for a 7:05 pace (~3:06 marathon); however, my number one goal is to re-qualify for Boston. I’m 40, so my time needs to be better than 3:15 (~7:25 pace). I was hoping a worst case 3:12 (~7:19 pace). I was wondering what you suggest for a pace strategy. Chicago will have various pace groups that I could join too. What are your thoughts on pacing? Should I run with the 3:10 pace team?

— B.



I love this question because it hits on two really important topics:


1) How should you approach pacing your race

2) How best to use pace groups


Let’s talk about the first aspect:


Your best approach to pacing your race


As a rule, it’s always going to be better to try and run even or slightly negative (faster in the second half of the race) when you’re looking to PR.


Yes, there are examples of people who go out fast, hit the wall, and still managed to hang on to run a good time. But from a physiological perspective, going out too fast is going to get you into a lot more trouble than going out too slowly. Partly that’s an issue with the availability of fuel for your body (running at a higher relative intensity burns through carbohydrates more quickly), and partly it has to do with the energy systems themselves.


going out too fast is going to get you into a lot more trouble than going out too slowly


Because of that, it’s always better to be conservative than aggressive at the start of your marathon. So in this example, where the REAL goal is 3:12, it probably doesn’t make a lot of sense to go out at 3:06 pace. If B is having a good day, he will be able to hold on and hit 3:06, but if he’s having a bad day going out at that pace may cause him to blow up and run 3:15.


I think it’s better to aim for 3:12-3:15 pace at the start of the race, and pick it up later if things are going well and he’s feeling good.


The other advantage of this approach is that it’s much more fun mentally to be picking up the pace and passing people late in the race rather than being passed. A big part of why the final miles of a marathon are so hard is a mind game and putting yourself in a good frame of mind will go a long way towards finishing strong.


As for the second part of this question:


The best way to use pace groups


Pace groups are awesome. If the race that you’re doing offers them, you should definitely take advantage of them. Of course a big part of the benefit will be keeping you on pace, but you’ll also get a boost running with other people aiming for the same goal, and you can mentally check-out for most of the race and go with the flow — saving mental energy for those really tough miles at the end of the race.




This is one big problem with pace groups that you’ll see over and over, and a couple others that will crop up from time to time.


The big problem is that by design, pace groups are led by people who are very comfortable running that pace — because their race times are much faster than that pace. Of course that makes it more likely that the leaders will be able to bring their pace group through at the correct time, but it also means that they may not have much (if any) experience running the pace they’re supposed to be running.


Because of that, you see pace groups start out too fast ALL THE TIME.


And, as I mentioned above, starting out too fast is a big problem in longer races! You may hear the pacers say “no big deal, we’ll slow down in the next mile” when they go too fast at the beginning, but not everyone in their pace group will be able to recover from that fast mile as easily as they will.


Other problems with pace groups can come on hilly courses when either:


A) the pacers don’t know where the hills are and/or


B) they have different ideas of how to run them.


There is a bit of a debate about whether you should strictly run the pace (e.g. 8:00 pace for every mile to run 3:30 regardless of hills), or slow down on the uphills and pick up the pace on the downhills to average 8:00. I prefer varying pace to account for hills, and of course you can’t really do that if you’re not familiar with the course.


Finally you can run into weird situations where all the pacers for a pace group drop out (seen it happen), can’t run the pace (seen it happen), or are running different paces and yelling at each other about it (seen it happen).


Bottom line: pace groups are a great tool to help you with your race, but you shouldn’t count solely on them to get you to your goal.


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, Men’s Fitness, and Competitor. For information on his coaching services, click here.