how fast are your feet? ask the polar rs800

By Coach Brendon Downey from EnduranceCoach.com

For a long time, cyclists have enjoyed the ability to monitor cadence and use it to manipulate their training. Clearly, the same could be useful for runners, but until now there just hasn't been a good tool to do it. Step in the RS800.

So how can you use the Cadence (leg turnover) feature to improve your running? Let’s take the marathon as an example.

We know that top marathoners run with a cadence of around 90-96 (180-192 steps per minute), whereas most beginners will typically run at 78-82 (156-164 steps per minute). A lower cadence increases the risk that your legs run out of power before you reach the finish line. At any given pace a lower cadence means a longer stride. You need to generate closer to your best power each step and lift your body up further against gravity due to the longer required 'hang time'. So translating that to running a full marathon (typically 30000-40000 steps), a small change in cadence can make a HUGE difference. The longer stride is also going to increase your risk of injury.

My rule of thumb is for first time marathoners to be at 86+ cadence at race speed (often around their typical training pace), three-hour marathoners to be 90+ and for those under two hours 45min to be 92+. So go out and see what your cadence is going to be at your expected event pace and then refer to my quick start guide to set up your RS800.

Quick Guide to Suggested Cadence for a Given Marathon Pace and Athlete Height

Marathon Time4 hours3 ½ hours3 hours2 ¾ hours
Pace 5:42/km 5min/km 4:17/km 3:55/km
Height
19084-8686-8888-9090-92
18086-8888-9090-9292-94
17088-9090-9292-9494-96
16990-9292-9494-9696-98

Drills that Increase Cadence

We know that for runners to go faster they have to increase their cadence and their stride length. But we also know that runners can learn to run with a faster cadence if they train specifically and focus on cadence.

In less experienced runners, a lower cadence is often caused by over striding, that is landing your feet too far ahead of yourself – this causes you to brake against your forward motion on each step, essentially working against yourself. The good news is that it’s an easy fix. Just have an experienced running coach take a look. A few simple drills can also help. Run some 50m strides and focus on leaning forward and landing on the middle of your foot (not on your heels). 5-6x50m strides after a warm up is a great way to set up a short run. Then during the remainder of your run focus on getting into the same body position and landing on your mid foot. Do this 2x per week for 6 weeks and you'll see huge changes.

Another great drill is what I call the 'Butt Kick'. Simply stride out and focus on “fast feet” by lifting your ankles towards your butt. Deliberately driving your elbows back at a faster tempo is a good way to increase your cadence generally.

When doing these drills keep your hips forward and avoid 'sinking' at the hips.

Monitor Cadence Regularly

If you are training for a marathon, choose a shorter event to test your cadence. A 10k run is ideal. Simply run with your RS800 on and see what your cadence is for each 2km/1mile segment (use the lap feature). Or if you have run a marathon before and you have a very good idea about your likely pace for your next one, do a shorter effort at your target race pace. By ensuring that your cadence is higher you will be increasing your chance of having the legs to bring home that last (hard) 8-10 km of the event. A higher cadence also lessens muscle damage in training and will enhance recovery.

By monitoring your cadence during your marathon build-up, you can track this as you go. It’s therefore not a bad idea to have some shorter pieces at race pace even as early as 4 months out (one 5min run at race pace will be enough early on).

Diversify Your Training

A key culprit for killing your cadence is the long run - yes they make you more aerobically fit but if they are done at a cadence of 80 (or less) and you don't include enough other training at 90+, then they simply kill your leg speed and add to the problem. One solution is to include some faster efforts during a longer run (i.e. 200m at 5km pace using a cadence of 90+ say every 30min, using a higher cadence “Fast Feet”). Another way is to 'split' some of your long runs, that is, run some of it in the morning and some of it in the evening. You'll find that your cadence is generally higher in the later run than in the second half of a continuous long run.

A treadmill run is also another great way to do this. You'll often find that you are less likely to over stride on a treadmill so you generally find yourself at a faster cadence especially if you use no gradient.

Work on Stride Length

Of course some more experienced runners already have good running cadence. In this case the key thing is to work on stride length by running more hills. I also like to alternate repetitions up steps and hill reps - it adds variety and forces you to run the steps two at a time. It’s also a good idea to use a shallower hill in preparation for flatter marathons. Typically for experienced runners it’s good to ensure that somewhere between 25-50% of total training time is focused on this. Ideally you do your greatest volume of specific strength work somewhere between 6-10 weeks out. If you have a naturally fast cadence then I think it’s okay to have the big weeks of this training closer to your event (6-8 weeks).

Another way to work on leg strength is to do faster training when tired. You need to be really careful when and how you do this, because obviously if you get it wrong it can leave you flat or injured. A good rule of thumb is to always do this type of training carefully and monitor for signs of overtraining or injury. A common way is to split a long run into a morning and evening run - in the evening include hills or hill reps (this is not recommended for people with less than 3 years of run training).

If you monitor your cadence while doing hills, make sure you are not killing your leg speed. If you find that you are, ensure that you do some work to counter that. I like to see runners do hill reps followed by 'fast feet' strides (see the example workout below).

I.e. 6-10x1min Uphill ending HR is around top of 80-90% HRmax (Zone 4).

Focus: Strong Leg Drive

Typically cadence will be 80 or so

Followed by 4x400m at 10k Pace

(again ending HR should be around the top of 80-90% HRmax (Zone 4)).

Focus: “Fast Feet”

Look for cadence to be ABOVE desired Race Cadence

To summarize, here is the quick guide to monitoring your cadence:

  • Monitor cadence with the RS800 specifically at expected/desired event pace

  • If it’s below ideal then work on increasing it by focusing on drills, speed work or “Fast Feet” running.

  • If it’s above, work on getting stronger by focusing on hills, hill reps or good form running when tired/fatigued.

  • Monitor during your actual event to save your legs for the last 8-10km

  • Analyze your cadence after events to see if you need to do more specific leg speed or leg strength work.

So just how fast are your feet when you run? Get out there and find out!

Happy running!

Coach Brendon's Quick Guide to setting up the RS800 for Cadence:

Firstly make sure that your Running Computer has detected your WearLink strap and that you've entered all your personal data.

Set up the S3 foot pod. For that you'll need to tell your RS800 that it should 'learn' a new S3 sensor, as follows:

Settings => Ok => Features => Ok => S Sensor => Ok => New Sensor => OK => Teach New Sensor? Yes. The RS800 should display “Completed”, if it doesn't, check that you have installed the battery in the S3 Pod and retry.

You should also tell the RS800 which sensor type you are using (it’s either Shoelace or Integrated).

Start => Settings => OK => Shoes 1 => Ok => Name of Shoe => Ok => Sensor type => Shoelace/Integrated (unless you are using the Adidas specific shoe it’s going to be the Shoelace setting).

Next you need to set up the display. My recommendation is to set the display so that there are the following three lines of information:

Upper: Cadence

Middle: Time or Lap Time, I suggest that you use lap time if you plan to run intervals.

Lower: Heart Rate/%HR or %HRR, whichever you prefer to use.

You do this as follows: Start/Ok => Settings => Ok => Display => Ok => Edit => OK => Select upper row information => CAD => OK => Select middle row information => OK => Stopwatch/Lap Time => Select lower row information => OK => Heart Rate .

Another useful variation is to use PACE on the lower line instead of HR. You can always go back and look at the HR data later using the Polar Software - this is particularly useful if you are aiming to run at a set pace (such as 4min/km or 8min/Mile) which is often what runners like to do in their final period leading into a marathon.

To change the heart rate view you need to do that separately, as follows:

Start => Settings => OK => HR View => OK => HR/HR%/HRR% => OK.

Personally I like the standard HR view – it’s easier to use and it’s what most of the athletes I coach relate to. But I understand that others relate better to the zones with HR% or HRR%. There is more on this in the Polar RS800 Manuals.