Forgot Password?
SEARCH
Connect With Us Facebook Twitter YouTube Google+
Sun 21st Jan 2018
EventsResultsTrainingSwimBikeRunProductsNutrition
©
STRYD: Powermeter for Running
Posted by: Editor
Posted on: Wednesday 4th November 2015


Bookmark This  |  Print This Page  |  Send To A Friend  |  Post A Comment

Running with Power - STRYD

As the power meter is approaching (almost) standard equipment for the competitive cyclist and triathlete, and chasing an improvement in your FTP is a core element of training for many, could a similar approach become commonplace in the seemingly simpler world of running?

One of the companies pushing forward the research and technology in this area is Stryd (www.stryd.com), and Philip Hatzis takes a look for us at the concepts behind both applying 'power' thinking to running, and the Stryd product itself.


While most triathletes are becoming happy with how power meters work on the bike, we are now seeing the introduction of power meters for running. This technology is exceptionally new and although initially may seem like just the next best “gadget" to have, the opportunities and training benefits of these products are exceptionally exciting.

Stryd (www.stryd.com) is one of two companies making significant leaps in bringing running with power to the market. Here we look into how it works and how it can revolutionise the way people consider run training.

Most people understand:

STRYD - Running Powermeter

If we think of this in very simple terms, such as a bicycle, we can consider Power as a combination of how hard you push the pedals (Force) and how quickly you spin them (cadence = velocity).

If we consider some fundamental equations though:

STRYD - Running Powermeter

Therefore by substituting for velocity:

STRYD - Running Powermeter

As we know that Force x Distance is Work Done (Joules):

STRYD - Running Powermeter

we are reminded that Power is work done per unit time. 

STRYD - Running Powermeter

Therefore, unlike most other power meters for the bike and indeed other power meters on the market, this is estimating how much work it requires for you to be moved through time and space rather than forces or torques (related) applied at a certain speed. 

When modeled in the laboratory against other force-velocity meters, the accuracy is very high, meaning the theory matches up to the lab results, their field results should also be correct. 

This is important and interesting when considering running compared to cycling. Whereas in cycling, the greater the power, the better the result (you can normalise this and compare amongst riders by the ratio of power to weight), in running, do more watts actually mean faster?

Well to answer that, we have to remember what this power meter is measuring – the work done per second. In other words, If your watts are up, it means you are working harder – we need to compare this to how fast you are moving for a given wattage. Now it is possible to compare your performances day-to-day. So, as per cycling, we will see an increase in watts meaning an increase in speed. However, unlike power on the bike, you could go faster for less power on one day or slower with more power or any such combination. Currently, there is not a significantly accurate enough method or data to compare running powers between individuals to understand power profiles between runners in the same way as cyclists (the error value is sat at 10%). 

This now starts to shed light on your efficiency. Therefore, in considering power meters with running, raw wattage does not help us alone. It has to be compared with the speed you are travelling at the time. Watts are not helpful. 

We now start allowing for discrepancies in biomechanical movements. Jamie, the Chief Technical Officer from Stryd says, the easy way to model running with a Stryd Power meter is to think about it measuring your centre of mass (around the heart strap) – this is bouncing above your legs. It then becomes a simple case of a mass on the end of a spring. Though this simplifies things beyond doing any of this justice, it gets the point across – everyone has different springs and different masses. Where on a bicycle you would have similar losses in power input, (e.g. drive train losses usually considered to be in the region of 4%), for a runner, losses in efficiency could be different leg to leg and will change as the runner (let’s kindly put it:) “relaxes" towards the later stages of a race. As the technology improves, and the understanding of the data also improves, the opportunity to just check and see what your efficiency reading is, will be the way that the runners start training and racing.

Stryd was born out of the lab from University PhD studies about three years ago and is now organised with several key personnel and partnerships including Craig Alexander (reasonably good triathlete…!) , Bobby McGee (Olympic Running Coach) and Allen Lim (Cycling Powermeter pioneer). Bringing their patent–pending power meter to market first with triathletes, extending it to runners and then  other sports, they really do hope to improve the way runners consider training and running. They have been working with Bobby McGee to create a significant first step in critical power testing and thus functional running zones with power. With no significant change in running training in the last 30 years, is Stryd going to be the next revolution?

STRYD - Running Powermeter

Though the whole concept is still in a very much research/beta phase at the moment, the data is telling and is in real time. The data being captured through this Stryd device and others like it, will be the defining way to train and race, much like it has been with cycling power. Take for example training stresses. With running previously, we had heart rate and pace as our main measurable methods of understanding how much training effect someone had exerted. Just from a practical point of view, when hitting a hill, the heart rate either goes up or the speed goes down to equal the same effort and thus stress. However, it is difficult to see that in real time (HR has a lag time) and at the moment there is no real-time way of seeing a Normalised Pace (allowing for the undulations of the terrain). Therefore, any understanding of running stresses is slight guess work. With power, we suddenly build a very good real-time method of understanding and measuring training stresses, resulting in better race planning and indeed better planning for recovery and tapering. Not to mention, more consistent and accurate interval sessions.

Over the course of the next few months and years, we can be certain that we will see power taking over the running population. Therefore, it will only be a matter of time until we see sessions based on functional power testing zones and runners discussing Watt Heart Rate they had Paced! Stryd seems very well placed to be one of this market's leaders, and it will be an exciting few months and years watching this product continue to develop and grow in applications.

Stryd is on sale now for $199.

STRYD - Running Powermeter, Craig Alexander


Related Articles
©
Earlier this year we looked at power in running...
Posted on: Wed, Nov 23, 2016 at 11:00
©
Tri Training Harder (www.tritrainingharder.com)...
Posted on: Thu, Oct 8, 2015 at 07:53
©
Meet Edward Brett and Philip Hatzis, the head coaches...
Posted on: Tue, Mar 12, 2013 at 15:20
 

 
Have Your Say