As a long time runner I sometimes, but only briefly, get nostalgic for the “good old days” when a wristwatch and rough idea of distance as measured by a car or bike trip around a loop were all we had. Numbered popsicle sticks distributed at race finishes told you where you stood while results were typed and mimeographed days late.

Cryptic paper logbooks kept track of training, all the better to keep secret your fitness from training partners and competitors at that next race.

That was then, this is now.

Today’s runner has it very different, with a proliferation of options to track performance, evaluate progress, share and be social about their running and those they follow, all of this literally worldwide and in real time at our fingertips. We now have a veritable buffet of options from GPS watches, sensors for heart rate and form, bibs with timing chips linked to SMS apps to provide instant and accurate on-course splits and results, music that can even be tuned to our cadence, apps, training platforms, digital coaching systems, and social running options all clamoring for our attention and dollars.

Running technology has rapidly evolved as wearable fitness and smart phone technology has exploded in recent years. Our many choices are now far more accurate and reliable and also easier to use now that gadgets are connected to phone apps. Rapid development and miniaturization of the electronics have added capabilities and led to far greater accuracy, longer battery life and easier-to-see screens.

So the buffet is set, a veritable smorgasbord of digital delights. But heaping everything on to the plate of a runner’s brain surely can lead to data overload. Instead, we will attempt to sort through the technologies to help narrow down choices which may be best suited to your individual running needs.

The basics of time, distance and pace

The starting point for all running data is the triumvirate of distance, pace and time. To get at this data on courses which are marked and accurately measured, a humble, low-tech wristwatch with a stopwatch function will do. Otherwise GPS data is the best way to know how far, how long, how fast and where we have gone. In addition to the basics of capturing your travel over the earth, GPS knows where you are and has opened running data to being mapped over terrain including for the all-important ascents and descents.

Dedicated GPS running watches or just about any running app on your phone can track your data as all modern phones have built-in GPS processors. GPS data is consistently accurate these days, generally being able to locate you within 10 meters anywhere on earth assuming a clear view of the sky. Still, you should take some caution in relying on GPS data during races because race courses are measured using the shortest tangents of the road. So unless your course is entirely straight, running the tangents is not always possible. Use the lap button on your watch to see your splits or keep track of the difference between mile alerts and actual markers. Depending how you carry your phone, during a race it may be easier to check a wrist device than your phone screen.

Heart rate data

While GPS data tracks your travel over the ground, what about the data on the status of our engine? Heart rate has long been the key measure of our physiological effort via “zone training” and capacity for effort measures such as our VO2 Max. We especially like to compare our lap and overall average pace to current heart rate to balance pace and cardiac effort. Traditionally measured with an EKG-style chest strap such as the new Polar H10 or the Suunto Smart Sensor, heart rate monitoring is increasingly moving to the wrist, forearm and even in-ear modules (sensor and LED lights illuminate blood flow). The advent of wrist-based sensing has ushered in 24/7 sensing to measure overall cardiac stress or intensity, get more accurate and complete sleep measurements and increase the practicality of heart rate zone-based training.

Strapless heart-rate sensing continues to improve in reliability with increased numbers of LED lights (such as the six on the new Polar M430) with wrist- and body-conforming watches and sensing earbuds. But for gym work and in-water workouts, chest straps still are the way to go. Off the chest devices require a close fit and can give erratic or no readings in water and at the extremities when blood flow is low, such as in cold weather or while clenching bars, doing calisthenics etc…

Your smartphone as a hub for on-the-run sensor data

Runners who rely on phone apps as their GPS tracker can add heart rate monitoring by pairing wrist and chest Bluetooth sensors such as those from Schosche, Mio, Tickr, Suunto and Polar and to rapidly emerging “smart” earphones. These earphones can combine music and phone listening and control, in ear heart rate and accurate elevation and ascent sensing via a built in barometric altimeter, a feature phones lack. Some such as the Vi and the Oakley Radar Pace, which incorporate shades, include voice recognition systems to partner with apps and call up stats from stashed smartphones. They are in the new category some call “Hearables”. Still in their infancy, these a require a precise fit to get accurate ear heart rate, and the voice recognition systems can be affected by wind and background noise.

Vertical data

Mountain and vertical focused athletes require accurate elevation and ascent data. While GPS watches can capture this information from GPS satellites, having a barometric altimeter on board gives a far more accurate and responsive read of elevation and ascent/descent. Commonly found in higher end mountain watches such as the Garmin Fenix, Suunto Spartan Ultra, and TomTom Adventurer, a barometric altimeter and its data can also be found in more fitness oriented watches such as the Garmin Vivoactive, as the barometer also helps in counting “floors climbed.”

Sleep-tracking data

With the explosion in fitness wearables and the increased sophistication of wrist based sensing of heart rate and movement, some run GPS watch makers have started adding sleep tracking to the the data collected. Sleep quantity and quality is key to running performance and, of course, well being. Movement based technology, the general method for tracking sleep, may overestimate sleep by confusing still awake times in bed with sleep. Fitbit’s current activity trackers, such as the Alta HR, do a better job as they combine movement and heart rate to get at a more complete view of sleep and how your sleep quality measures up.

Recovery and physiology data

Once we get that sleep, where do we stand as far as recovery and physiological status for training are concerned?

With more accurate sensing Fitbit, Garmin, Polar, Whoop and Suunto can now estimate VO2 max and in some cases other performance-readiness factors, such as heart rate variability (HRV). HRV variability is often used to judge recovery, but it was previously difficult to measure. Our conclusion after many months of testing the Whoop Strap is that a single morning value doesn’t tell the whole story or predict performance even when combined with sleep statistics. The human body is just too complex. It does help form better habits—as the result of low sleep or those extra beers is clear in the data the next morning.

The Under Armour RE shoe line (Record, Velociti and Europa) incorporate a force sensor in one shoe and in addition to accurate indoor treadmill distances its jump test starts to get at muscle fatigue, which is missing from the recovery calculations of overall cardiac intensity, sleep and HRV of the others. It would be ideal if the data provided by the technologies started to provide a more complete and cumulative picture of status from engine to tires, but we’re not quite there yet.

Form and running mechanics

Data can now be captured about our running form and running bio mechanics. The most recent models of GPS watches can monitor our cadence, a higher value without resorting to over striding can be associated with greater running economy. Going beyond cadence, the Garmin Run Dynamics Pod, Lumo Run and SHFT (all worn on the mid-body) give guidance on overall body position and metrics such as right/left balance, pelvic rotation and vertical oscillation. The Lumo and SHFT pods give audio feedback and easy-to-follow coaching via their apps. The Garmin pod gives feedback via a field on their watches which we find is more difficult than audio feedback.

Stryd and RunScribe focus on forces measured down lower at the feet as they are clipped to shoes. They can provide insight into pronation, ground contact time and impacts, and in the case of Stryd a true measure of running power. The RunScribe device, in particular, provides a wealth of information to evaluate the effect of different shoes on body mechanics and to potentially help identify changes in mechanics indicating an injury or the status of your recovery from one.

Altra’s Run IQ system takes data from specially modified shoes with embedded sensing layers to provide form coaching on the app screen and with audio cues. It turns out the most actionable changes it recommends are not about how and where a foot strikes the ground or cadence, but the running posture in our upper body as the key to the rest of the kinematic chain. The challenge with having technology built into a special shoe is that it limits tracking to running only in that pair of shoes (which has a limited life span of 400-500 miles), whereas other devices with clip-on sensors can do much the same and provide the versatility of being able to work on other shoes in your quiver.

The ultimate goal of these running form coaching and tracking systems is to be able to give practical actionable information and tips based on the data that can help gradually improve form or pick up on and give pointers as form deteriorates in the later stages of a hard effort. But the ones that will be most successful are ultimately the ones that will provide that information and coaching as obtrusively or unobtrusively as the runner wishes for the task at hand.

Where does all of my data go?

So now that we can accumulate all of this data, what should we do with it? Where should we house it? What’s the best way to share it and create social interaction around it? A multitude of apps and platforms provide a dizzying array of choices—some open, some closed off gardens—this despite the fact that most of the underlying data collected by devices and apps is in a standard format called GPX.

Some platforms such as Nike+Run Club and Runkeeper (owned by ASICS) don’t allow easy or any sharing of your data to other training platforms but do allow, as all platforms do, plenty of sharing to more conventional social media platforms. For example, Nike+ does now allow easy or automatic data importing from Polar, which is a more full-featured serious training platform than the social-sharing vibe of Nike+. Others, such as Strava, welcome data from any device or other platform while also providing a phone app for those who track by phone. Polar, Suunto, and Garmin, all GPS watch manufacturers, allow easy exports, but make imports relatively difficult. Their own platforms tend to be data-rich with deep training features but with a lighter social component. Given these complexities, selecting the best device, app and platform to store your data requires some thought.

Beginner runners tracking with a phone and seeking motivation, challenges and a strong social component will benefit from Runkeeper, Map My Run and Nike+Run Club. Nike now also offers a stand-alone run tracker for the Apple Watch Series 2 with onboard GPS, as does Runkeeper and Map My Run. Runkeeper and Map My Run offer apps for Apple Watch Series 2 and some Android Wear 2.0 watches.

More advanced runners seeking detailed analysis of performance with comparisons to others on the same routes or segments along with a more performance-based social component may gravitate to Strava as their repository for data while using a GPS watch from Epson, Suunto, Garmin or Polar, among others. Strava offers a phone run/cycle app and stand-alone versions for the Apple Watch Series 2 with GPS and some Android Wear Watches.

If you use a phone app and want basically all the features of a training watch including pairing to a multitude of Bluetooth sensors as well as complete open sharing of your data to dozens of platforms, consider the excellent iSmoothRun app. It doesn’t pretend to be social on its own, but it does keep a detailed log of each run. Its upcoming stand-alone Apple Watch Series 2 GPS app has many customizable data fields, a first for Apple Watch.

Evolving rapidly and light years ahead in capabilities and ways to share data than even a few years ago, wearable technology for running should inform, motivate, and provide a shareable record over time. All modern run tech provides basics of pace, distance, time, location and, more recently, heart rate data. The other elements of sleep, recovery and form tracking, coaching, motivation, challenges, data portability and social features become the factors to balance in deciding which technologies, platforms, apps, devices and sensors are best for your specific needs and interests as a runner.

But remember, if the past is truly prologue, you can expect the progression of running technology to continue, and that means new devices, software and sensors will transform everything we know about run tracking today.