There's a running sign that says, "If you see me collapse, pause my Garmin." While GPS running watches can track many things such as pace, steps per minute and even the length of your stride, they can't measure running effort and intensity, which is important to running faster and staying injury-free.
For this reason power meters – once used for cycling – are gaining popularity with running coaches and athletes for their ability to assess running performance, endurance, and technique.
Old fashioned new tech
Running coach Nathan Fenton uses power meters with his clients to help them achieve new PBs.
"Cycling power meters have been used since the late 1980s to measure torque applied through the pedals," says Fenton.
"Due to the three-dimensional motion of runners - instead of the directly applied force of cyclists – it wasn't until 2015 that power meters for runners became available."
Fenton found that training with a power meter on a bike changed everything for the better and was curious to see its application for running power.
"Initially, I was very sceptical about how a power meter like the Stryd could measure something that is not a constant force – as running is a very different action to cycling. But I found that a few cycling concepts also applied to running with power," says Fenton.
"I could see their cadence, ground contact time, and vertical oscillation, which allowed me to analyse how efficiently they were running. However, I very quickly saw the benefits of using power zones for training metabolic fitness."
Four steps to improvement
As power meters give objective data both during and after a run, they can help runners improve their pace in four ways:
- Controlling intensity
Training with specificity is the best way to prepare for an event. Knowing the precise intensity to train at is very effective at improving performance.
- Quantifying workload and fatigue
The stress of each training session can be better quantified using a power meter. This helps to understand the training stress of each session and the recovery required.
- Controlling energy expenditure during races
Pacing strategies can be created using power. This assists the athlete with knowing how hard to push during a race and keeping intensity consistent.
- Measuring fitness and progress
When threshold power increases, it means the athlete can run faster with less effort. This is a quantified performance improvement.
So, what do power meters measure and how do they work? Fenton says the technology measures running power.
"Power meters measure functional threshold power, which is the highest power output an athlete can maintain for roughly 60 minutes without fatiguing. They quantify speed, terrain change, form, and fatigue, so a runner can adapt to any course in real time — from a sprint to ultra-distance," he says.
"I look at power meter data in two separate categories: quality of technique, and metabolic load. Quality of technique uses metrics such as cadence, vertical oscillation, leg spring stiffness, form power, and ground contact time. These metrics tell me how efficient an athlete is and whether their technique might cause an injury in the future.
"When looking at metabolic load I use power zones, like heart rate training to determine the intensity of a run. This gives the athlete objective values for easy runs, all the way through to speed work."
Because power meters use accelerometers, which model power output with high correlation they are highly accurate. A recent study showed that Stryd power meters estimate force with 95 per cent accuracy when compared with a laboratory grade force plate.
But any data without good analysis is useless, and Fenton admits that using a power meter gives you so much information, but it can be overwhelming.
"Just pick one or two metrics that make sense to you and notice how they change with your training. There is no right answer, only information and feedback so be objective and iterate your training repeatedly," he says.
To get started, he recommends runners record power data for one month and just observe the information. Then after a few weeks, do a threshold test to determine your performance baseline. From there you can analyse the data or get a running coach who specialises in power to help you understand where changes can be made or what training you should be doing to see a noticeable change in your performance.
The goal of one day completing an ultra-marathon inspires running fanatic Laura Hill to clock up the kilometres each week. With a day job in the corporate world, Laura loves nothing more than lacing up her runners and hitting the pavement to clear her mind and challenge her body.
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Have you tried using power meters? Share what benefits, if any, you received in the comments section below.