Race Day Run Cadence vs Training Cadence

Derrek Sanks

During my IMLP run, my Garmin cadence alert was constantly alarming.  My cadence alert is set to alarm when my cadence goes below 168.  I was making effort to increase my cadence to no avail.  Looking at my Garmin stats, my average cadence was 164. This was usual so I looked at the average cadence for all my long runs since January 2015 and noted I consistently average 174.  As an aside, my cadence for 5K/10 is 184 and HM is 178.  For me, cadence plays a big roll in my running efficiency.  Is it normal for cadence to drop in an IM marathon?  How can I improve this for my next IM?  Thanks.

tim cronk

Derrek, Personally I do not track cadence nor put much value in it... Instead I just focus on short,quick, easy turn over relative to the pace I am running and let cadence fall where it may.... Like you and probably most people my avg cadence is a bit faster on intervals , 5k/10k vs. HM and M.... The only thing I can think of is, did you do walk breaks in your training long runs to simulate the aid station walk breaks you must of had at the IMLP marathon? And if you did where they of the same time frame? It would not take very long at a walk to adjust the avg cadence down....

Al Truscott

Posted By Derrek Sanks on 07 Aug 2015 07:49 AM

During my IMLP run, my Garmin cadence alert was constantly alarming.  My cadence alert is set to alarm when my cadence goes below 168.  I was making effort to increase my cadence to no avail.  Looking at my Garmin stats, my average cadence was 164. This was usual so I looked at the average cadence for all my long runs since January 2015 and noted I consistently average 174.  As an aside, my cadence for 5K/10 is 184 and HM is 178.  For me, cadence plays a big roll in my running efficiency.  Is it normal for cadence to drop in an IM marathon?  How can I improve this for my next IM?  Thanks.

Derrick - Unless one makes a very concerted effort, cadence will be directly correlated with running speed, up to a point. I find that to be true myself, with my long run cadence @ about 90, and my 5k cadence getting up to 100 (180-200 by the metric Garmin uses). When I first started checking pace during IM marathons, indeed, I noticed my pace down in the 85-86 range. So I made a concerted effort to try and quicken my pace during races, sometimes successful, sometimes not. At my best, I am able to replicate my LRP cadence on race day despite going about 30 sec/mile slower. More often, I will be 85-87 (170-174). All these numbers so far are while running.

To check Tim's point, I looked at average cadence, which I have overall and by mile. I found, both on long runs (when I walk every mile or so to drink and re-set) and in races, I found my avg cadence, which includes the walking segments, to be about 2-3 (4-6 by Garmin's count) below my running cadence.

To your question, in 2012/13, when I first started using a foot pod to measure cadence (I now use the Garmin HRM strap/watch system), I made a concerted effort to work on getting my race day cadence up to 90 (while running). I did that by focusing primarily on bricks, especially the first two miles, when I (and I assume others) have the strongest tendency to have a slower turnover. It worked, and at IM AZ that fall, I was consistently @ 90 rpm while running. I've since gone off the wagon. So this question is a stark reminder to me to make this another of my points of training emphasis over the next 3-4 months. A quicker cadence despite the slower speed IMO saves energy at the end of the long Ironman day.

So, you gotta pay attention on your bricks and especially on race day to really, really try and get that turnover up when your legs are tired and you;re going slower. The start of bricks and the very end of long runs are the best times to do that, IMO.

Derrek Sanks

@Tim - Good point on comparing training avg cadence with no walk breaks to race day with walk breaks. Thanks. So I agree my average on race day was a little higher than 164 due to walk breaks but it wasn't higher than 168 because that's where my Garmin is set to alarm. Garmin alarms the instant you go below the set rate and my alarm was going off very frequently throughout 25 of the 26.2 miles. I don't fret over cadence either but I've worked to improve my cadence to where I don't have to think about it too much...like you, I focus on short, quick turnover. I use cadence a check point after my runs to make sure I'm not slipping back into old habits. 172-175 is a natural cadence for my long runs at Z1 pace (+/- 40") and is why I was surprised I could not hold that for the IM marathon and the alarm had me focusing on short strides/quick turnover.

@Al - To your point, my 168 cadence alarm is in range of 4-6 below my normal LRP, so perhaps I was in the "normal reduced cadence during IM marathon" range. I will make a note to work on increasing my cadence during the last 4-6 miles in my long runs (on tired legs)...good suggestion. Thanks.