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Archives for June 2023

Garmin Stamina and Stamina Potential – A Native Feature Gauging Fatigue

Garmin Stamina and Stamina Potential May Just Be the Enlightenment Tool for Cyclists and Triathletes!

Garmin Stamina and Stamina Potential Cover Graphic
Garmin Stamina is a new, Native feature that shows, in realtime as well as in post-ride analysis, how much you’ve got “Left in the Tank”, as well as the POTENTIAL for what’s “Left in the tank”! Let’s learn some more.

With the release of the ’40 Series of Garmins (the 540, 840 and 1040), as well as a host of watches, Garmin has included the Garmin Stamina and Potential feature. This native Field looks at energy use, intensity, heart rate and other elements to gauge ‘Just how much is left in the tank’ when a cyclist or runner is exercising. It’s one more tool that a cyclist, runner, or triathlete might be able to use for training, breakthroughs, or in an event.

What Is Garmin Stamina?

Garmin Stamina and Stamina Potential Screen Garmin 1040
Ride ‘Blue’, and Garmin Stamina and Stamina Potential will still decline. Fatigue happens, no matter what.

Garmin Stamina is defined as a visible metric that reveals just how much a cyclist has left, in terms of residual energy, power and work, at any capacity, over time. When a cyclist rides harder, Stamina drops faster. When the cyclist recovers, Stamina rebounds. Garmin Stamina is measured in %. If a cyclist is fresh and recovered, Stamina will start at 100%. If this is their second workout of the day, or they haven’t adequately recovered from a previous effort, it may start at <100%.

What is Garmin Stamina Potential?

Garmin Stamina and Stamina Potential Early In an Interval Set
Garmin Stamina is using a pretty complex, really proprietary, algorithm to measure fatigue and work capacity. I think it’s looking at that gool ol’ Wattage, Heart Rate (Variability), Temperature and Cadence combination. It’s pretty cool.

Garmin Stamina Potential shows just how much fatigue is affecting a cyclist’s ability to generate power. I remember Dr. Allen Lim, in 2004, telling me about requiring his athletes to use at least 600 KiloJoules of energy prior to performing intervals, because “500 watts after 600 KiloJoules is a LOT HARDER than 500 watts after just 200 KiloJoules!” And he’s right.

Garmin Stamina begins on a scale of 100-0%, and it declines with Garmin Potential as a ride progresses.

The Garmin Stamina Page On Your Garmin Head Unit

If you have a new ’40 Series, turn on the Garmin Stamina Page by following these steps:

  1. On the main screen, tap on the ‘Sandwich’ Square.
  2. Tap on ‘Activity Profiles’.
  3. Pick a Profile (I have ‘Road’, ‘Indoor’, and ‘Mountain’).
  4. Tap on ‘Data Screens’.
  5. Scroll up and down and look to see if ‘Stamina’ is shown as a page or not. If not, press ‘Add New’.
  6. You should find ‘Stamina’ in the options, and add it.
  7. The Garmin head unit will then offer you ways to slide the ‘Stamina’ page around in order, until it’s where you want it. As a Lefty, I tend to swipe Left-to-Right, so mine is Second-from-Last.
Garmin Stamina Page Procedure
I call the ‘Settings’ button the ‘Sandwich’ button because it looks like two slices of bread with a thin slice of ham in between!

 

Garmin Stamina Settings Page 2
Once you’ve clicked on the Sandwich button, you’ll see this page. Tap the ‘Activity Profiles’ button.

 

Garmin Stamina Page 3
Go to the Profile where you want to add a Stamina Screen.

 

Garmin Stamina Click on 'Data Screens'
Click on ‘Data Screens’

 

'Stamina' Will be near the bottom of the list.
‘Stamina’ Will be near the bottom of the list.

 

Garmin Stamina Reorder Option
Slide the Stamina Page around in order so you can swipe to it or in the case of the 540, you can use the buttons to slide the pages around.

Back-Arrow out until you get to the main screen, and then tap on the Profile itself. Swipe until the screen shows up.

Garmin Stamina and Stamina Potential Page
What you end up with is a page that looks like this.

There are 3 Fields, including a Stamina Bar with Stamina and Stamina Potential in numbers, followed by a Wattage Graph, and finally, a traditional Heart Rate Graph. Above the Stamina Bar is an ‘Estimated Distance’ value, and it makes me wonder if that might not be useful for an Ultra-Cycling event. Hmmm.

How to Use Garmin Stamina and Stamina Potential

Garmin Stamina Stamina Potential 60-60s
I’m purposely avoiding revealing the wattage and heart rate values on this chart, because I honestly believe I couldn’t go any harder, or get Stamina down below 0%. These were Billat 60-60’s, and you can see that I drove the Garmin Stamina Potential down significantly as well.

Remember the ground rules:

  • Once you start a ride file, Stamina and Stamina Potential will begin to decay.
  • The rate of decay is dependent upon time spent at different intensities.
  • At low intensities, Garmin Stamina and Stamina Potential will decay at the same rate. If you ride at a higher intensity, the Garmin Stamina value will drop faster than the Garmin Stamina Potential value.
  • Garmin Stamina can rebound, but it will never be higher than Garmin Stamina Potential.
  • “500 watts after 600 KiloJoules is harder than 500 watt after 200 KiloJoules!”

A 20-Minute Effort With Stamina and Stamina Potential

I’ve been using Garmin Stamina and Stamina Potential for a couple of months now, especially in my Indoor Virtual Studio over at VQ Velocity. We recently rode some ubiquitous 2 x 20 minute efforts right at or just above Threshold. Here are the results of the first interval.

20 Minute Garmin Stamina and Stamina Potential Chart Interval 1
While I was not paying complete attention to this metric, I was watching it out of the corner of my eye.

 

I’ll crowd the chart a bit, to show some other physiological metrics, just so you can see how ‘hard’ this interval really was.

20 Minute Garmin Stamina and Stamina Potential Chart Interval 1 Chart 2 with SmO2
Garmin Stamina and Stamina Potential seem to be pulling from a combo of heart rate variability, wattage, and maybe respiratory rate. I added the SmO2 values from Moxy to show that I actually was at my physiological threshold, which was ABOVE the threshold value provided by Garmin (and other metric platforms, btw….). See my previous blog about SmO2 Tipping Points, and Borrowed Time.

On-Screen, the Page looked like this…

 

Garmin Stamina Stamina Potential 20 Minute Effort
Stamina will decrease faster than Stamina Potential when you’re riding over your Threshold. Stamina Potential is a little slower, but I’m finding that it definitely helps me gauge my effort on work, especially later in a ride.

Look carefully at the Red, Black, and Clear Line. You’ll see an ‘arrow’ where the red meets the black. This is the point where the Garmin Stamina is declining faster than the Garmin Potential Stamina. Red means decline. Green means recovery. Potential will NOT recover during a ride. It may plateau, but it won’t rebound.

For context, here’s the graph of the SECOND 20-minute interval……

Second 20-minute Interval Garmin Stamina Stamina Potential
Physiologically, I got some training effect out of this effort, but had I followed the physics and tried to hold the same power that I had held in the first interval, I would have blown up. Stamina at 3% is an indicator that you’re ON BORROWED TIME. When Stamina and Stamina Potential are BOTH pretty low, you’re cooked, and it’s time to go home.

Billat 60-60s With Stamina and Stamina Potential.

Garmin Stamina Stamina Potential 60-60s With Comments
The 60-second interval intensity for these efforts was roughly 350-375 watts. Watching Stamina and Potential, I was able to gauge just how much I had left in the tank, before exhaustion.

 

Above is the post-ride overview of a set of Billat 60-second intervals with 60-second recoveries. Notice how Garmin Stamina pulls Stamina Potential down over the course of the ride.

Here’s what the ride looked like on my Garmin 1040.

Garmin Stamina and Stamina Potential Early In an Interval Set
This was Interval #7. Stamina is now in the gutter, but I still have some Potential left, so let’s keep going. 

 

Garmin Stamina Billat 60-60s Interval 11
11 Intervals in, and Stamina hovered between 15 and 3%. Stamina Potential dropped about 2 points per 60-second effort.

 

Garmin and Garmin Potential Screen 60-60 Intervals Last Effort
This was my last interval before calling it a morning. The Stamina got down to about 2% in the interval before, but I was unable to perform it for the full 60-seconds, and Stamina rebounded artificially high. While this last interval was high quality at 374 watts, Stamina only came down to 8%, while Stamina Potential reached its’ lowest level, at 24%. I was definitely fatigued.

For context, here is a link to the ride itself on Garmin Connect…


And here is an image of what Garmin gave this ride, in terms of Aerobic TE, Anaerobic TE, EPOC, and Training Effect.

Garmin Stamina Stamina Potential Workout Summary With EPOC Aerobic Anaerobic TE Scores
While I’m ignoring the ‘Tempo’ summary, this was a highly effective Aerobic and Anaerobic Workout that took days from which to recover.

Pay Attention to Garmin Stamina and Stamina Potential

Garmin has been at this game of product development now for about two decades. They bought a company (FirstBeat) with even deeper roots and history. They’re an Aviation company, a sport metrics company, and a travel logistics company. But they’re really onto something here. These developments use a history of science, a slightly conservative approach, but one that is loading features into rugged devices, and then helping recreational athletes improve their fitness in a holistic way. That’s what’s so fascinating about the Garmin Ecosystem. Their motto is, “Beat Yesterday.” And as both a coach and an athlete, using features like Garmin Stamina and Stamina Potential, I am.

Functional Threshold Power Chart Garmin Stamina and Stamina Potential
Something must be working….. The tools are all here at OBC and Garmin Connect.

I’ll post later about the possibilities of BREAKING this fatigue model, and how the model later adapts, but it’s really rare.

Thanks for reading, and ENJOY THE RIDE!

Garmin Sleep-Time Stress

What is Garmin Sleep-Time Stress?

Garmin Sleep-Time Stress Chart
This is the Garmin Sleep-Time Stress Chart. There’s not much information about it, but I think it could provide yet another clue about how to identify problems with your sleep, and how to address those issues. Let’s find out.

I just stumbled across a new chart on Garmin Connect, and I’m curious to know more about it. It’s the “Garmin Sleep-Time Stress” Chart, and I THINK it’s a metric that works with overnight HRV Status, to provide another window into sleep quality. If you own a Garmin watch with a NIRS and optical heart rate sensor, it provides another window into sleep. There’s very little information about it in Garmin’s own Forum or Wiki, and questions asked have not been answered by anyone at Garmin HQ in Kansas.

That said, I think there’s something to this metric. Here are my initial thoughts…

Garmin Sleep-Time Stress – Where to Find This Metric?

First, you need to have one of the more advanced Garmin watches, and you need to have heart monitoring turned on for overnight measurements. Then, using the online website account for connect.garmin.com, follow these pages:

Health Stats Menu Garmin Connect
In Garmin Connect, Open the ‘Health Stats’ drop-down menu….

 

Health Stats Submenu Sleep Garmin Connect
Then click on ‘Sleep’.

A new page will pop up. Click on ‘Sleep Score’, and then ‘Stress’.

Garmin Connect Sleep Score and Stress Submenus
This chart is not easy to find, but get to ‘Sleep Score’, then ‘Stress’, and click on the box.

And finally…

Garmin Connect Sleep-Time Stress Graph and Tips
…You get this chart, with several paragraphs that sort-of explain it, and how to improve your sleep. Honestly, though, I think we need more ‘Do This, Don’t Do That’ effort put in. I’d also like to see temperature or tossing and turning, to see how that affects sleep.

Several Garmin Sleep-Stress Charts for Comparison’s Sake

Here are a couple of charts of mine from this year. Looking at these charts for myself and my clients, two things stand out: Overnight stress usually declines as the night goes on, and it takes a special kind of night or individual to hit this ‘ideal’ (more like ‘mythical’) figure of ’15’.

Garmin Connect Sleep-Time Score 23 Average Sleep
This is what most of my nights, and most of my mid-50s male clients Sleep-Time Stress Charts resemble. Medium Stress, with declines over the progress of the night, followed by intermittent medium stress (waking) moments. Cracking the Sleep Code is going to be the absolute hardest thing I think I’ve ever done in my 30-year history as a cycling coach.

 

Garmin Connect Sleep-Time Score 17 Average Sleep
This was last night’s Sleep-Time Stress chart. I’m almost completely off of alcohol, but we had a stressful day yesterday, and I took a Sominex. So this is what a good night’s rest looks like on drugs. I also went to bed before 9pm. The result? Today I had a 15 watt breakthrough on my Threshold, and year-high 20-minute Mean Max Power……. Sleep Score was an 83, which is high for me.

 

Garmin Connect Sleep-Time Score 29 Average Sleep
This was one of the worst looking charts that I had recently, and yet it offers a completely different perspective from the Sleep Stages chart, which would have me believe that this had been a decent night’s sleep. However, I scored a ’52’ on the Garmin Sleep Score.

 

Garmin Connect Sleep-Time Score 29 Sleep Stages Comparison
Here’s the corresponding Sleep Stages Graph. It does show that I awoke twice in the early sleep period, but I was hoping that the ‘Deep’ sleep would win out. Hmm. It seems like the REM sleep that traditionally hits me right before I wake up, is the period when I’m least-stressed. I’m also starting to see the point behind 7-8 hours of sleep every night. It just helps get that extra time in LOW STRESS SLEEP.

 

Once Again – Sleep Is A Critical Part of Training and Recovery

Garmin just recently peeled back the window on their collection of Meta-Data in the Garmin Connect Ecosystem. For those who may be upset about this, a couple of things; ALL of the platforms are doing this, and have been for a while. Furthermore, it’s more information than you can even think. Garmin though, honestly, I don’t think they have a handle on just what they’re presenting to the population. The stuff in Garmin Connect is GOLD, but I really think I’m one of the few people in the world who are actually using it and sharing this information. I’m the interpreter, and while I may be a Mad Scientist, I am definitely not a Real Scientist. That said, it’s all there.

I’m going to just stick my neck out and say it; if I could find a way to get consistent, deep, restorative sleep on a consistent basis, including medication, I would do it. I understand why a certain Pop Star might have felt desperate enough to employ an Anesthesiologist to ILLEGALLY aid him in sleep (which led to his death….) You’ve read the story about my Lunesta Sleepwalking episodes and how completely wrecked I was physically, after taking these meds. But I’ve done it all; I quit drinking, quit caffeine after 3pm, we have blackout shades, white noise, pink noise, a Muse S EEG forehead reader, fans on my body, cold rooms, weighted blankets, scheduled intimacy….. all of it. The results have been modest.

The few things I see that we can all do to get better sleep, and hence, better overall health and results from our exercise as cyclists and triathletes are these:

                                      • Drink more water.
                                      • Abstain from Alcohol beyond 1 drink.
                                      • Go to bed early.
                                      • Regular intimacy before bed. Yes, I said that. Hump.
                                      • Cold Rooms.
                                      • Noise abatement.
                                      • Blackout curtains or shades.
                                      • White or pink noise.
                                      • No distractions. No TV, late night ball games, etc.

Garmin Sleep-Time Stress; let’s keep watching.

Most of my clients are now on Garmin Watches as well as Garmin Head Units. We’ll be looking at the data in private and together, to help glean just what is working, what isn’t working, and why. I’m not going to go all Puritan, but I’m going to watch that Sleep-Time Stress Chart and see where the balance point is, for myself, my clients, and you, my readers. I will also going to take a look at the ‘Breathwork‘ meditation app in the Garmin Fenix watch lineup, to see if that helps. I’m not a huge fan of meditation, but then again, it may be worth the effort.

Thanks for reading, and ENJOY THE RIDE!

 

Garmin Connect HRV Status Update

Garmin Connect HRV Status Is FINALLY Showing Some Improvement – And I’m Feeling It!

This Garmin Connect HRV based Ecosystem Is really getting interesting. I’m literally using just about everything Garmin; The Scale, the Watch, and the Head Unit. I probably ought to buy a Neo 2t and a pair of pedals, but I’m fine for now with my current setup. I know there is debate over the accuracy of NIRS, the validity of the FirstBeat HRV claims, but let’s face it; no other company is showing the commitment to data collection and general health guidelines like Garmin Fitness. It’s not cheap, but I think the long-term gains for overall health and wellness are working. The Garmin Connect HRV Status shows overnight heart rate variability, and I think the combination of regular exercise, a new bed, a more private bedroom, a LOT less alcohol at night, and a LOT more water throughout the day, is leading to better sleep, and better rides.

***Before we go any further, I’m curious to know if you think these blog posts are informational. IF you feel like they are, then .

Garmin Connect HRV Status Shows How Sleep Is Leading To Better Workouts – and Vice-Versa

Have a look at my 6-month TREND for HRV Status.

6 Month Garmin Connect Training Status Report Including HRV Status
This is the 6-Month Training Status Report from Garmin Connect. Specifically, look at the third chart; HRV Status. It shows the incredible stress I was under at the end of last year, which resulted in a severely suppressed HRV status. Once I started simply walking the dogs last winter, and we had a home we could call our own (that’s a whole other story that remains unfinished), the HRV Status began to stabilize, albeit still ‘low’ (stress) and ‘Tight’ (again, stress). Once I started training regularly again in February of this year, however, HRV Status began to stabilize, and it’s FINALLY starting to rebound, which I’ll show in the next image. Also take a look at the Garmin Connect Acute Training Load, below HRV Status. As my training load grew, HRV Status actually improved, and it was on the days where I rode an acute overreach that the HRV Status dipped back into ‘Unbalanced‘ Territory. We’re Tempering Action With Wisdom.

Now, here’s the corresponding 28-day trend, which is a bit of a close-up of the 6-month chart.

28 day Garmin Connect HRV Status April 26 through May 23rd 2023
The dots on this chart represent a rolling 7-day average of HRV Status, measured at night, from the time I fall asleep to the time I wake up. The grey zones represent a baseline range. I’ve been told that my range is too low (too stressful) and too tight (again, too much stress), but I’m encouraged by the STABILITY I’m seeing in this chart, and the RISING TREND as well. This means that I AM recovering better, and sleeping better to some degree. And as we know, a good night’s rest is critical to a good day’s performance.

Is it leading to better results?

Honestly, I don’t yet know. I am confident that my Threshold is improving, and I believe that my Anaerobic Work Capacity is growing. More importantly, I’ve started losing weight, and I just ‘feel’ better, all around. The first chart shows that Vo2 Max is improving, and I think I could probably break 300 watts for 20 minutes if I really tried. But I’m not ready yet to tax my system like that. I want to focus on consistency, and on learning as much from this Garmin Connect ecosystem as possible. There is SO MUCH DATA available!

Garmin Connect Body Weight 1 Year Graph
I’m convinced that a good night’s rest and improved overnight HRV Status, leads to better workouts with higher calorie counts. This leads to a more optimal weight. I’ll continue to avoid alcohol and increase my caloric expenditure, especially on weekends, to try and achieve my goal of 70kg. If I start to lose fitness because I’m too light, I’ll report that.

Garmin Connect HRV Status and Periodization

If you look at my Acute Training Load chart, you may see that the black line, which is a rolling 7-day average of TRIMPS. It’s bouncing near the bottom of the Green zone, known as the ‘Optimal Range’. This is intentional. I’m backing off on the intensity for the week, to avoid a fitness plateau and stale performance. My clients on VQ Velocity are really enjoying this hybrid approach to Physiology and Physics. 8 weeks in, and we’re set for one of our best summers of activity yet. I’ll be attempting a new 20-minute breakthrough next week, along with a new Threshold and Vo2 Max. I like to attempt these indoors, because it’s consistent. But if the HRV Status or Sleep Scores trend in the wrong direction, I’ll listen to my body, and will delay Breakthrough Efforts until I’m recovered and mentally prepared.

HRV Status Is One More Metric That Can Help With a Holistic Approach to Training, Recovery, and Fitness.

I sell these watches. I love these things. Any cyclist who owns a Garmin head unit and is half-serious, needs to be looking at this stuff. I DO think it’s accurate enough and consistent enough to be effective. I can’t wait to see just how fit I can become, with my clients as well. This is my new platform going forward. We’ll be migrating to this HRV-based ecosystem for the majority of our cycling, and then use wattage for those SUPRA-THRESHOLD efforts that require taxing the Central Governing Theory to its’ limits.

Thanks for reading, and ENJOY THE RIDE!