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Terra API
Terra API

11 April 2022

HR Zone training: What is it, and how can our wearables help us with it?

What is heart-rate zone training?

When it comes to training, heart-rate feedback is an excellent way to monitor workout intensity and to put together training plans that help you improve fitness. Most wearables that track heart rate also allow you to train using heart rate zones that are preprogrammed, or that you set up for yourself. Before we dive into this style of training, its important to understand what the three different heart states are:

  1. Resting heart rate - relatively self-explanatory, this is the rate your heart beats at while you're doing no activity whatsoever. A variety of factors determine your resting heart rate including age, gender, fitness level, and even medications. As your fitness improves, you'll find your resting heart rate fall
  2. Recovery heart rate - the amount of time it takes for your heart rate to return to its resting heart rate after vigorous exercise. Like resting heart rate, it improves with fitness
  3. Heart rate max (HR max) - the fastest at which your heart is able to beat. This is the key spec for setting up your training program. Whilst traditionally this is calculated by subtracting your age from 220 (e.g. at 30 years of age my HR Max would be 190) a more accurate measure can be taken by running a stress test in a lab

What are the HR training zones?

The key principle behind HR training is that different heart rate levels engage different aspects of your physiology, and a good training plan will work in multiple zones to improve overall performance. Heart rate zones also determine what energy source you're using - carbs or fat. The higher your heart rate gets, the more your body starts to rely on glycogen from carbs for fuel.

Whilst the American Heart Association defines two zones for heart rate training (moderate intensity 50%-70% of HR max and vigorous intensity intensity 70%-85% of HR max), it can be broken down into five categories:

  1. Zone 1 (recovery / easy) 55%-65% HR max. Warmup / warmdown zone, easy training
  2. Zone 2 (aerobic / base) 65%-75% HR max. Longer training sessions, sustainable for many miles
  3. Zone 3 (tempo) 80%-85% HR max. Pushing the pace to build up speed and strength
  4. Zone 4 (lactate threshold) 85%-88% HR max. Lactic acid builds up too quickly to be processed and fatigues muscles
  5. Zone 5 (anaerobic) 90% HR max and above. Max speed zone. Body is exerting at full effort.

Typical training plans will utilise multiple training zones, and you won't train in each zone for an equal amount of time, especially depending on your goals. A distance runner may spend more time training in the lower HR zones than say, a sprinter. Somebody looking to build their endurance would want to train in lower zones so that they can sustain it for longer periods.

Elite athletes often pay close attention to their heart rate whilst training. For example, during a one hour time trial Lance Armstrong would often spend almost the entire test with his heart rate at around 200 bpm in order to push his body to the absolute max.

How can our smartwatches help us with this?

Smartwatches are designed to track and record our heart rate whilst exercising and some even give us useful information on how much time we spend in each heart rate zone. By optimising our training and exercising according to heart rate zones we can maximise performance.

Through the Terra API, we provide connections to a range of different devices so that your users can track their steps.

Below is a list of the wearables that track your heart rate today:

  • Garmin Fenix series, Venu series, Lily, Approach, Vivoactive, Forerunner series, Instinct series, Enduro, Descent series, Mk2 series, Epix, Tactix series, D2 series, Vivomove series, Approach series, Vivofit, Marq series, Quatix series
  • Fitbit Versa series, Charge series, Inspire 2, Sense, Luxe, Ace 3,
  • Apple Watch all series
  • Polar Grit X Pro, Grit X, Ignite series, M430, Unite, Vantage series,
  • Withings ScanWatch series, Steel HR, Move ECG
  • Oura ring Gen 3, Gen 2
  • Samsung Galaxy Watch all series, Galaxy Fit2
  • Suunto 9 range, 7 range, 5 range, 5 peak, 3 range, Ambit3, Core range, Traverse
  • Wahoo Elemnt Rival Multisport GPS watch
  • Xiaomi Mi Watch

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