I realize this thread goes back a ways, but I thought I’d add a different perspective. I’m new to running as part of transitioning to triathlon from competitive bike racing.

When I started last year my form was typical new runner. Cadence about 150 to 160, over striding and plenty of bounce. And my running times, although not terrible, were middle of the pack and nowhere near in line with my cycling results. So I decided to look into form and quickly came across the subject of cadence and that it was probably more efficient to get that up above 180.

The thing I wanted to mention is that in studies from cycling they found that a cadence above 90 rpm is better, but not because it is metabolically more efficient. It is better because it favors the bodies aerobic system more than its relatively limited anaerobic systems. Bike races are typically 2 to 4 hours long, so that’s a big deal. A well trained aerobic system can use fat stores almost limitlessly, rather than the limited supply of cellular glycogen, which is the fuel for the anaerobic system.

Put simply if you take away all resistance, and turn over the pedals of a bike 50 times a minute, that is going to require less metabolic output than turning over the pedals 90+ times a minute. Once you add load, however, the benefit is that the absolute force per revolution required to move the rider and bike forward is less at the higher rpm. And since it is less at the higher rpm, the aerobic system can carry more of the load.

In competitive cycling it is common to use a watt meter in the crank to measure absolute work output, along with HR and cadence. It is simple to see this principle in action by riding the same patch of road, at the same watt output at 50 rpm, and then again at 90 rpm.

At the lower rpm it is much harder to turn the pedals over, even though the work output (and speed) is exactly the same.

Foot strike characteristics notwithstanding, this leads me to believe that similar principles may be at play in running, that a higher turnover likely allows the aerobic system to take more of the workload.

For me personally, I’ve taken this to mean 180 isn’t some magic number, but more that quicker turnover (generally above 180) is likely better because it is less work per step for the same speed. Granted on a bike, its a simple matter to change gears and keep cadence the same. It’s been a learning process to vary my stride length in order to keep cadence high at lower speeds.

At any rate, just another perspective. Thanks again for the interesting discussion.

You are correct, rusty math skills…can’t believe nobody else caught that!

Thanks.

You could also try an app like iSmoothRun which will show cadence in real time. The Garmin 620 will also do cadence and estimate stride length with the HRM-Monitor.

Thanks for the reply.
Yes were doing the count as you run technique and he did seem to be taking fewer strides although it wasn’t a particularly accurate test.
I might try to do some more testing to get a better idea.

Great question. The easy way to figure it out would be to simply count the number of steps you each take in 30 seconds and double it to get your cadence (steps/min). If your cadence is the same, then stride length would need to be the same, but stride length relative to leg length would likely differ and thus your form might be a bit different. Tough to wrap my head around, would be interesting to know the cadence numbers!

Be grateful to hear your thoughts.

Nope, perfectly normal. My cadence regularly goes over 200 on fast intervals, and may drop below 170 when I run with my beginner 5K group at 10:30-11:30 min/mile pace.