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Many newer Garmin watches ([[Garmin 620| 620]], [[Garmin 920XT| 920XT]], [[Garmin Epix| Epix]], [[Garmin Fenix 3| Fenix 3]], etc.) combined with a special chest strap will provide extra metrics that can give insight into your Running Form. The Garmin watches will provide these metrics in real time, allowing you to see the effect of changes in your form. These metrics include:
* Vertical Oscillation. This is how much the torso moves up and down with each stride. It is generally believed that less [[Vertical Oscillation ]] is a better, but I suspect that this is an oversimplification. It's sometimes a thought that a greater vertical oscillation [[Vertical Oscillation]] will result in greater [[Impact]], but this is not the case. [[Impact]] is how quickly you decelerate, so landing hard can result in less vertical movement but a shorter, more intense deceleration. It's even suggested that greater vertical oscillation [[Vertical Oscillation]] will result in more braking force, but that does not seem reasonable. I believe that some are part of a runners vertical movement is likely to be elastic in nature (consider a bouncing rubber ball), some of the vertical motion will be while the runner is airborne (ballistic), and some of the vertical motion is the vertical deceleration as the runner lands. So it seems likely to me that excessive vertical oscillation [[Vertical Oscillation]] is bad, but it's a tricky to know what excessive is likely to be, or how to correct it.
* Ground Contact Time (GCT). [[The Science of Running Economy]] generally shows that longer Ground Contact Time is correlated with poorer [[Running Economy]].
* Ground Contact Time Balance. This is the relative Ground Contact Time ratio of the left and right feet, which will reveal potential imbalances in the body.
* Computed metrics. The Garmin watches will use the basic metrics to calculate things like stride length (based on cadence and pace), and Vertical Ratio (vertical oscillation [[Vertical Oscillation]] to stride length ratio).
[[File:RunningDynamics.jpg|none|thumb|300px|Garmin's Connect web site shows the metrics gathered using the HRM4 and [[Garmin Fenix 3]].]]
=RunScribe=
''Main Article: [[Lumo Run]]''
Like many other devices, [[Lumo Run]] uses accelerometers to measure body movement, but uniquely (so far) Lumo places the accelerometers at the small of your back. This allows Lumo to not only detect [[Cadence]] and [[Vertical Oscillation]], but also breaking and pelvic movement. The measurement of braking force is rather different from [[RunScribe]], as Lumo measures how much your overall body slows up with each stride, rather than measuring the deceleration of your foot in touch down. I believe that both approaches are important, and give valuable insight into possible biomechanical problems. In addition, Lumo will measure how much your hips (pelvis) will drop from side to side, and how much it rotates (twists). Lumo is available Lumo Run is available for <jfs id="B01K22SOYE" noreferb="true"/>. I really wish that Lumo would measure [[Impact]], as it would be great to know how much of the foot strike [[Impact]] reaches the hips.
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[[File:BSX1.jpg|none|thumb|x300px|The dashboard view of the BSX app, showing previous results.]]
=RUNTEQ Zoi=
Zoi places sensors on both the foot and the torso. This allows it to gain a little more insight than other sensors as it knows about the movement of the foot and the torso independently. Eventually I expect to see a company produce a group of sensors placed on each foot, each knee, and the pelvis, which would give insight into the movement and [[Impact]] forces across most of the body. The Zoi only has one Footpod, so it doesn't give you detailed foot strike information in the way that [[RunScribe]] can, though you could see them adding that functionality in the future. The Zoi gives quite a few metrics, including [[Cadence]], Ground Contact Time, [[Vertical Oscillation]], breaking (at the torso, not foot breaking), of [[Foot Strike]] type (fore, mid, heel), Foot [[Impact]], and some [[Pronation]] information. Zoi has a smartphone app that provides real time feedback and post-run analytics, but I've not seen any support for displaying metrics on a watch. Currently Zoi is on pre-order in Europe for 150 EUR. I'd like to test this system if I can get hold of one. The approach is similar to the SHFT system, though the SHFT uses a 9-axis sensor and it's not clear what the Zoi uses.
=RPM<sup>2</sup>=
RPM<sup>2</sup> (Remote Performance Measurement/Monitoring) is a pair of insoles that fit into your normal running shoes. These insoles measure pressure and use accelerometers to measure movement (a little like Sensoria). The details are not entirely clear from the web site, but they claim to measure [[Cadence]], Ground Contact Time, [[Foot Strike]], and "acceleration power". The system also claims to measure running power, though I'm not sure of the methodology. The RPM<sup>2</sup> system measure pressure in four areas (Sensoria has three), giving a [[Pronation]] measurement. There are notes that RPM<sup>2</sup> insoles are not waterproof, which is rather disconcerting, and if you run in different shaped shoes the fitment is likely to be problematic. The sizing of the insoles needs to take into account the position of the ball of the foot to ensure the sensor is in the right place. The system supports Bluetooth to connect to your phone as is common with running sensors. The RPM<sup>2</sup> can also connect to an Ant+ watch, though it's a bit of an ugly kludge. You need to have your phone with you, and then plug in the Wahoo Key adapter via a lightning-to-30 pin adapter to transmit Ant+ to a watch. The Wahoo Key and adapter are all extra bits you have to buy. The system can also be used as a power meter for cycling. Their web site is [https://www.rpm2.com Remote Performance Measurement/Monitoring].
* '''Vertical Oscillation'''. I've evaluated the accuracy of Vertical Oscillation by looking at the movement of my torso using HSV and lasers. This proved to be rather more tedious and time-consuming than I'd anticipated, but the results were worthwhile (to me at least.)
* '''Foot Strike'''. I've done some simplistic testing of sensors that measure [[Foot Strike]]. I've run with these sensors in my usual heel strike, plus running forefoot both with and without my heel touching down. I've used HSV to verify that my foot strike pattern is what I think it is, as it's easy to be mistaken. I didn't include midfoot strike as this is tricky to get exactly right, and tricky to verify using HSV. This approach to measuring Foot Strike is based around the point of first contact, not the point of highest force. Personally, I believe that the latter approach is far more relevant, but harder to measure.
* '''Power'''. It's tricky to measure [[Running Power Meters| running power ]] without access to VO<sub>2</sub> equipment, so I've resorted to some simple tests. An incremental treadmill test should show an increase in power with an increase in pace; if it doesn't pass that test, then it's probably not much use.
=Ideas For The Future =
This section documents a few ideas I've had for running sensors, partly to inspire manufacturers, and partly to disclose these ideas so that they cannot be patented in the future.
