Whether you’re a seasoned marathoner or just starting on your fitness journey, you’ve probably heard fellow runners toss around the term “VO2 max.” But what exactly does it mean, and why does it matter? Your VO2 max score represents the maximum amount of oxygen your body can utilize during intense exercise, indicating your level of cardiovascular endurance and aerobic fitness. For runners, knowing your VO2 max can help you benchmark your current ability level, track training progress over time, and estimate your race day potential.
But how do you actually measure this elusive metric outside of a lab? Enter wearable tech. The best rated golf rangefinder watches with activity tracking like the Garmin Fenix 7, Garmin Vivoactive 4, Apple Watch Ultra 2, and Samsung Galaxy5 Pro Golf Edition have algorithms that can estimate VO2 max during exercise using data like heart rate, duration, pace, and GPS. Their fitness watches and bike computers can generate on-the-go VO2 max scores during activities like running, cycling, and walking. No fancy lab equipment required!
I will help break down exactly how Garmin devices calculate your VO2 max. I will tell you what physical activities allow for estimates, which devices support them, and tips for improving your score. I will also teach you how features like all-day wear heart rate monitoring and Garmin’s Body Battery can generate VO2 max estimates even on your rest days.
What Activities Allow for VO2 Max Estimates?
Before your Garmin device can generate a VO2 max score during exercise, you first need to meet certain requirements. These criteria vary based on the type of activity being recorded and the specific capabilities of your device.
Running
Most Garmin running watches require a minimum of 10-15 minutes of continuous running while wearing a heart rate monitor. For outdoor runs, your route needs to be recorded with GPS tracking. Treadmill runs can provide estimates on some devices, but the accuracy is reduced without the GPS data.
Your heart rate should remain elevated to at least 70% of your maximum for the duration of the run. This ensures you are putting in enough sustained effort to trigger a VO2 max calculation. Intervals or walk breaks can throw things off.
Cycling
Cycling activities require 20 minutes of uninterrupted riding while wearing a heart rate monitor. For the best results, you’ll also need to pair an external power meter with your bike computer. The combination of heart rate, power, and duration data produces the most accurate cycling VO2 max estimates.
As with running, your heart rate should stay elevated to at least 70% max for the full ride time. Maintaining a steady effort is also key—large variability and intervals will reduce the accuracy of the score.
Walking and Hiking
Brisk walking for at least 10-15 minutes with a heart rate monitor is needed to generate a VO2 max estimate for most Garmin watches. The walk should be continuous with elevated heart rate just like with runs and bike rides. GPS data improves the accuracy similar to outdoor running.
Compatible Garmin Devices
Not all Garmin devices support on-device VO2 max estimates for all activity types. These are several top models that can generate VO2 max for running and cycling:
| Device | Running VO2 Max | Cycling VO2 Max |
|---|---|---|
| Forerunner 245/945 | Yes | Yes |
| Fenix 5/6 | Yes | Yes |
| Vivoactive 4 | Yes | No |
| Edge 530/830 | No | Yes |
Check your device’s specifications to confirm which activities allow VO2 max estimates. Ensure your watch software is up to date, as Garmin periodically adds support for new activity profiles.
Improving Your VO2 Max Estimates
Following the activity requirements is the first step to getting accurate VO2 max data but you must keep some additional things in mind:
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Warm up for 10 minutes before starting the activity to elevate your heart rate
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Maintain a steady, hard pace or power output throughout
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Run or ride outdoors with GPS for most accurate readings
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Make sure your heart rate monitor is snug against your wrist or chest
With some practice, you’ll get a feel for which workouts produce the most reliable VO2 max scores. This can vary based on the device algorithms. Use the estimates as a guide, but don’t get hung up on any single number. Trends over time are most meaningful for tracking fitness.
How Does the VO2 Max Algorithm Work?
Once you’ve recorded an activity that meets the requirements, your Garmin device can estimate your VO2 max using its proprietary algorithm. But what exactly goes into this calculation?
Running Calculations
For outdoor runs tracked by GPS, your watch collects data on distance, time, heart rate, and pace. It feeds these metrics into a formula that estimates the maximal oxygen uptake based on your performance.
In general, longer distances at faster paces with lower heart rates will produce higher VO2 max scores. The watch is calculating how efficiently your cardiovascular system can deliver oxygen to your muscles during sustained high-intensity exercise.
Cycling Calculations
Cycling VO2 max estimates also incorporate distance and heart rate data. But the addition of power meter metrics provides even greater insight into your anaerobic efficiency.
The algorithm analyzes your power output relative to your weight and heart rate response. Generating more power with lower heart rates equals better oxygen utilization and a higher VO2 max.
How Accurate Are These Estimates?
Garmin’s VO2 max calculations have been validated against results from direct gas analysis testing. But some error is to be expected when predicting lab values from smartwatch data.
Factors like weather, fatigue, and differences in wrist vs. chest heart rate can all impact the estimates. Take any single VO2 max score with a grain of salt. The best practice is to look at trends over multiple activities to gauge your true fitness.
Tips for More Accurate Estimates
While Garmin’s algorithm is robust, you can optimize your devices’ calculations with some best practices:
- Calibrate your power meter before each ride
- Avoid frequent stopping/starting during activities
- Discard outlier estimates from very hot/cold workouts
- Make sure your heart rate zones are set correctly
- Get periodic VO2 max tests in a lab for comparison
Generating VO2 Max Estimates Through All-Day Wear
So far we’ve focused on VO2 max estimates during dedicated workout activities. But many Garmin devices can also generate scores based on your all-day heart rate and activity data. This allows you to monitor your fitness even on rest days when you aren’t recording any runs or rides.
Garmin’s Body Battery Feature
Fitness devices like the Venu 2, Forerunner 245, and Fenix 6 series use data from the optical heart rate sensor, stress levels, and activity intensity to calculate a proprietary metric called Body Battery to track your energy levels throughout the day.
Higher intensity activities drain your Body Battery, while rest and recovery recharge it. The watch algorithms leverage this information to estimate VO2 max, even without a structured workout.
No Special Activity Needed
The main advantage of the all-day VO2 max calculation is that you don’t need to go for a special run or ride. As long as you are wearing your Garmin watch with wrist heart rate enabled, it can passively estimate your aerobic fitness.
However, the accuracy of these scores is lower compared to those generated during a dedicated sustained activity. They are best used as a supplement in between workout-based estimates.
It Takes Time
Don’t expect your watch to start spitting out daily VO2 max estimates as soon as you put it on. The algorithm needs time to establish baseline readings of your heart rate variability and typical activity levels. It may take 3-4 weeks of all-day wear before you start seeing VO2 max scores from this method.
Good For Tracking Trends
Due to the variability inherent in passive estimates, a single all-day VO2 max score isn’t very meaningful because only tracking long-term changes and trends will reveal improvements or decreases in your aerobic fitness over weeks and months of wear.
So next time you’re crunching the VO2 max numbers from your latest interval workout, remember your watch is also hard at work calculating this metric 24/7.
Improving and Tracking Your VO2 Max Over Time
So you’ve been wearing your Garmin watch 24/7 and recording VO2 max estimates from both activities and all-day wear. Now what?
Train to Increase VO2 Max
While VO2 max is largely genetic, dedicated training can increase this metric by 5-20%. Focus on workouts that elevate heart rate for sustained periods:
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Tempo runs: Maintain hard but controlled pace for 20-40 minutes
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High-intensity intervals: Short/fast intervals with full recovery (e.g. 4x800m @ 5K pace)
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Lactate threshold work: Slightly below max effort for up to 60 minutes
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Hill repeats: Run hard up short/steep hills for 30-90 seconds
Complement these challenging cardio workouts with strength training 2-3x per week to see the greatest gains.
Monitor Trends Over Time
Don’t obsess over each individual VO2 max score. because you can make great gains in 4-6 weeks of focused training. Expect more gradual improvements as your fitness level increases.
Use VO2 max trends as positive feedback that your hard work is paying off! When your scores plateau, change up your workouts to keep challenging your body.
Consider External Factors
Don’t panic if you see a major drop in VO2 max after being sick, traveling, or taking time off. Your fitness level doesn’t change that rapidly. Give yourself a few weeks to get back into peak shape before drawing any conclusions.
Remember that variables like hot and cold weather can also impact the estimates. Focus on the big picture using trends over multiple weeks. With smart training, you’ll see the numbers move in the right direction.
Get More from Your VO2 Max Data
But Garmin leverages the VO2 max metric to unlock even more performance features. These are several of the ways to maximize your VO2 max data.
Race Time Predictions
One of the coolest features is the race predictor. Using your VO2 max estimate and race times, Garmin can forecast how fast you could complete other distances.
For example, if you have a 45:00 10K time and a 50 VO2 max, it may predict potential finish times of 21:00 for a 5K and 1:50:00 for a half marathon.
Fitness Age
Your VO2 max is used to calculate fitness age in the Garmin Connect app. Having a lower fitness age than your chronological age indicates above average cardiovascular fitness!
Training Status
The training status tool factors in your VO2 max trends to determine if you are maintaining, improving, or detraining. This provides guidance on how your recent training load is impacting fitness.
You can use this data to identify when to push harder or back off. It provides validation that your VO2 max is responding to changes in training.
Additional Data = Better Insights
The more you leverage VO2 max within Garmin’s ecosystem, the greater benefit you’ll gain. When used across platforms like your watch, phone app, and computer software, it unlocks a treasure trove of performance data. More data equals better training, faster results, and achieving your fitness potential.
Using VO2 Max to Take Your Training to the Next Level
Garmin has unlocked the ability to estimate the VO2 max measurement of cardiovascular endurance right from your wrist. No running on a treadmill or lab equipment required!
But generating those sought-after VO2 max scores takes some know-how. Now you can run, ride, and walk with confidence knowing how to optimize these estimates during exercise and all-day wear. Consistently meeting the activity requirements will ensure you get meaningful data to guide your training.
While the scores themselves provide great feedback, you will reap the biggest benefits by tracking trends over time. Improving that VO2 max number by even a few points over a few months is cause for celebration!
Use your VO2 max trends as the benchmark for evaluating your training program. If the numbers plateau, don’t be afraid to shake things up. Try new workouts, add strength training, or take an extended rest.
Wearing a Garmin watch gives you access to world-class training metrics once reserved just for elite athletes. Make VO2 max your trusty data guide on the journey to fitness breakthroughs.
