Not hitting the active zone--60+ woman

[Coloradodaisy]

I am a 60+ woman gifted a Fitbit about 10 days ago and I have become fascinated.  I have an athletic background, but have been largely sedentary for about 10 years, exercising 3 days a week or less, mostly easy walking or hiking. In earlier decades I have been a competitive cyclist (forty-fifty years ago, so does this even matter?), and a marathoner (almost 30 years ago, gulp!) The point here is that I know how to train, what it feels like to over-train, and I backed off on my athleticism because I realized I had a tendency to obsess.

So I get this new FB: The first day my resting HR registers at 46. I want to test the FB parameters, so I go for a hike (I live at 8,000 feet in the mountains) in my neighborhood. This means the first 1/2 is uphill, downhill back home. Our mountains and trails are steep. My normal pace does not get me into the active HR zone. The walk did not even register as an activity on my FB. The next day I added 10 pounds of weights in a pack. This time for a 33 min walk I got 6 mins of active zone credit. It felt like I deserved more credit, but whatever, I'll go harder next time. I needed to hit 91 bpm to get credit. 

So a day or two later I go out again with the weight in my pack and try to push myself. My HR still did not go into the active range on an incline. After about 15 mins I picked up the pace making a pointed attempt to hit the target and make it for the recommended 22 mins.  I was breathing hard and finally in the required range. At the top of the hill, my HR quickly went below the active level, so I had to start running to stay in the zone. I do not run anymore. I was getting irritated.

I ended the workout with 1:31 mins total, 25 mins in the target zone. It felt like a workout that reached the 80% HR intensity, but FB looked at things differently. 

Now all of this I can live with, especially since I did feel a wonderful endorphin rush after the intense workout, but for three days I was noticeably fatigued, and my resting HR is steadily climbing. FB now says it is 51.

I researched max HR calculators, and found information on adjustments for gender and age. As a result I reduced my FB max HR to 151. I then remembered that during my marathoning days my max HR seemed to be lower than expected, so I am playing with this. I still have a hard time achieving active minutes on my walks and hikes.  However FB gave me 85 mins active credit for cleaning house and cooking a holiday dinner!!!! Give me a break. 

Now I have been using FB long enough get a daily readiness score. After using my device for a week for workouts and holiday activity, I feel pooped. My whole body feels fatigued and I know I need to rest. FB readiness score says I am ready for an intense workout.

My goal is to remain fit and increase fitness during aging--heart health, I guess, also strength, and to support my mental well being. Also I want load-being activity.  What approach should I take to build up, and how should I use the FB info?

[alexthecat]

@Coloradodaisy it sounds like you know what you're doing and have a lot of familiarity with heart rate zones. Which Fitbit device do you have? Do you think it is measuring your heart rate accurately? The Readiness Score is based on your heart rate as measured by your Fitbit. If that isn't right, nothing else works. 

[Coloradodaisy]

I have the Charge 6. The default settings tell me to get 22 mins a day of exercise in the 60%+ range, 5 days a week. That seems ways too hard for me at this point, given how hard it is for me to hit what they have set as 60%.  I have been assuming that my resting HR is correct, so I guess I can confirm that. The more I use the FB, the active HR seems to be recording accurately. I had to make a few adjustments for it to pick up my HR and my sleep. My thought is that my Max HR is not input correctly. It defaulted to 159. I changed it to 151. Now I have it set at 141, which may be a bit low. Also thinking that the standard parameters of fitness that the FB algorithms work from are not suitable for me: At my age I take longer to recover, and with such a low resting pulse, and good sleep, maybe FB thinks I am more ready than I really am. 

[Coloradodaisy]

Just took a manual read--the device is right on with my resting HR. Just measured 54 bpm 

[alexthecat]

@Coloradodaisy I would suggest also manually checking your heart rate when you are exercising. Fitbits generally do a good job measuring heart rate at rest. During exercise may be different story. If you're getting active zone minutes for doing stuff around the house, but not when you're actually exercising, it sounds like you're not getting an accurate heartrate measurement during one or both activities. 

You're new enough to Fitbit, that I wouldn't take the Readiness Score too seriously. The app has enough data to give you a score but, in my experience, it takes about a month for the score to be fully calibrated. During that time, do what you need to for your body and let the app figure out what is happening. Instead of following the Readiness Score, make it follow you. 

[Coloradodaisy]

thanks. This is very helpful. Wish I still had my old heart rate monitor 

[alexthecat]

@Coloradodaisy I use a chest strap heartrate monitor when I'm doing cardio and I've done that for more than 20 years. The comfort isn't the best, but the results seem very reliable. 

[Coloradodaisy]

I had a Polar hrm back in the day. Liked it a lot. Last night slept great and am feeling much better but still not fully recovered. Resting hr is now registering on the FB as 47. Still a tad elevated. It feels weird but good to be active again. I expect to be ready for a more intense workout again tomorrow. I swam yesterday, but I am so slow the FB doesn't care, lol. It feels good in the muscles, but not aerobic. Twice the FB has registered me as sleeping when I am just reading on the couch or in bed. Changed the sleep setting to sensitive to see if that creates better accuracy. I'm liking being able to watch my sleep quality, and the assessments are mostly ringing true so far. Do you integrate your HRM data with your FB stats or use them separately?

[alexthecat]

@Coloradodaisy it sounds like you are doing a good job of listening to your body. I hope you'll keep that up!

Fitbit doesn't accept data from a chest strap. I use a Polar strap and the Polar Beat app on my phone for cardio. I do not have a Polar watch. I track cardio sessions with my Fitbit too, but I don't pay as much attention to that data because it is generally less accurate. 

If your Fitbit thinks you're sleeping when you're awake, try to remember to move once in a while. Your resting heartrate is low, so that may be part of the issue, but if you don't move at all for an hour, your Fitbit may decide your sleeping. 

[MrBosco]

The good news is you seem to have retained an extraordinary level of cardio fitness for someone who, by their own estimation, has been largely sedentary for 10 years.  I think those hikes may have been more valuable at keeping your fitness up than you might realize.  The bad news is that the default 'Active Zone Minutes' criteria used by Fitbit are going to be less useful to you than they might be for someone of average fitness.

I have the opposite problem to you - I am extremely unfit compared to you, with a high resting heart rate, and as a result I get Zone Minutes far too easily.  I get zone minutes pulling on my pants in the morning.

To give an example - on Wednesday I went for a 35 minute walk and got 57 zone minutes - 27 'moderate' minutes and 8 'vigorous' minutes, which count as double.  By some Fitbit magic 27 + ( 2 x 8 ) = 57 - I have no idea how that's supposed to work.

Today (Thursday) I walked the same route at almost identical pace and got 35 zone minutes - no 'vigorous' minutes this time.

The difference between the two walks?  I drank alcohol on Tuesday night.  While I was physically well-rested on Wednesday I was (apparently) still a little poisoned after my holiday drinks.

Does that mean my walk on Wednesday was 63% more effective at improving my fitness than my walk on Thursday?  I don't think so - and nobody has ever recommended vodka as a tonic for improved cardiovascular health.  Does it mean my easy walks on city streets are better exercise than your hikes on steep hills?  Absolutely not.  It just means that there is no device, mathematical formula or algorithm that applies equally well to a former marathoner who hikes hills regularly as to a fat man with a hangover.

Perhaps creating a custom heart zone might be useful to you for comparing the benefits of different forms of exercise or different walking/hiking routes.  This can created (in the Android app) at 'Today' -> 'Heart' -> Cog icon at top right -> 'Heart Rate Zones' -> 'Custom Heart Zone' and should enable you to 'aim' for a specific heart rate range during exercise rather than the 'one size fits all' Active Zones that Fitbit uses.

Best of luck with your experimenting 🙂

[Coloradodaisy]

Thank you, @MrBosco MrBosco! You exactly communicate my experience! And I love your colorful illustrations. The FB magic calculation has kicked in a number of times for me and given my mysterious credit (or denied credit equally mysteriously). I feel good exercise and muscle activity when swimming, but according to the FB I might as well be sleeping. (I have had to learn to swim VERY easily so that I don't start gasping and drown. I'm not a good swimmer). Walking across the (hot springs) pool, however, after a soak, becomes a minute of vigorous activity. 

I am most loving watching my sleep and recovery patterns. I don't know your age, but at mine, recovery after higher intensity activity is soooo long. I need to give myself several days of recovery after one of these intense FB inspired workouts.

My best solution for the lack of zone credit has been to set my max heart rate at 141. FB thinks my max HR should be 159 or higher. I know that is crazy high for me. 141 may be low, but the settings seem to be giving me the right workout. I have a custom zone going, but FB doesn't use the custom settings to give me the atta girls I seem to crave 🙂 

My boyfriend has been diagnosed pre-diabetes, so his motivation is similar to yours (I looked at your profile). I am supporting and benefiting from his increased interest in health and fitness. He recently proactively (e.g. no aggravating symptoms) went to the cardiologist and got enough bad news that he will be going on a statin, in addition to the diabetes medication, which he had been trying to avoid with diet change. The cardiologist said that diabetes is essentially a heart disease since it increases the likelihood of so many heart issues. 😞   In his research for preventive options, BF discovered his medicare plan B gives him a FB every year. He gave me his first one, and he'll get another credit in 2024, so next week he will order his own. I will teach him how to use it 🙂 

My own motivation I guess is to be less of a workaholic. I don't even make much money, but my life has long been centered on, I am slowly learning, an unhealthy relationship to work. Weirdly, it's what kicked in when I stopped having the unhealthy relationship to athleticism, which probably was learned from my mother, who her entire life obsessed (for minimal reason) about her weight. These endorphin highs from my new FB workouts are making me experience a new joy and it is wonderful. Leaning to savor and nurture this experience without falling into obsession is my path.

I'd like to be in your cheering section. It's so helpful to have a community to do this with.

[MrBosco]

I'm glad to hear that you're finding ways to use your Fitbit to aid with motivation @Coloradodaisy  I too find it helpful, even though I wish the math behind it was more consistent and more applicable to every user.

Regarding diabetes, you may want to let your boyfriend know about recent studies into remission, if he hasn't discovered it already.  In short, it seems that the great majority of cases of Type 2 diabetes (and thus pre-diabetes) are probably caused by visceral fat - stored in and around internal organs - specifically the liver and pancreas.  What causes the body to store fat in terribly unhealthy places is complex and to some extent a mystery; diet, exercise, age, gender, race and ethnicity all seem to play a role.  Burning off this fat, ideally as soon after diagnosis as possible, can effectively 'cure' type 2 diabetes for most people.  It's not really a cure as you have to keep the fat off for the rest of your life and monitor your blood sugar levels via regular blood tests to be sure it hasn't returned.  Remission can mean however that no medication is required to control it and the negative health effects such as heart disease and eye problems are likely nullified.

Neither my GP (family doctor) nor my diabetes specialist doctor mentioned remission to me, I had to discover it for myself, and you can bet that no pharmaceutical company is investing in research along this line given how profitable some diabetes drugs can be.  The best information and research is coming from and is funded by diabetes-related charities and medical associations.  I've included some links below to some of the clearest information I've found.  My goal is to burn off 1% of my body weight every week until I lose a total of around 20 to 25 kilos - a fifth to a quarter of my starting weight.  This should be enough to burn off my belly fat and I'm hoping this will also be enough to get rid of the problem visceral fat.  No doctor can currently, confidently say if that will do the trick or not, but I'll let you know if the 'cure' has worked sometime in July or August.

Best of luck with your exercise goals and a very happy New Year to you 🙂

https://www.diabetes.org.uk/guide-to-diabetes/managing-your-diabetes/treating-your-diabetes/type2-di...

https://www.diabetes.org.uk/about-us/news-and-views/weight-loss-can-put-type-2-diabetes-remission-le...

[Coloradodaisy]

Wow, great information. We just finished reading Peter Attia, Outlive, which peripherally mentions the organ fat issue, but was not so specific. This is very helpful info. By all accounts your plan will be good for you--both the exercise and the weight loss. Attia's premise is that our medical system pays attention to the wrong things at the wrong time, and helps people way too late in the game. It sounds like your diagnosis has been very motivating for you! Thanks for sharing.

[alexthecat]

Hi @Coloradodaisy! I'd like to comment on this quote from one of your earlier posts:

"I feel good exercise and muscle activity when swimming, but according to the FB I might as well be sleeping." 

Your Fitbit is not able to measure your heartrate accurately when you are swimming. This is true for all trackers that use optical heartrate detection, because light travels differently through water. You can let your Fitbit detect your heartrate in the pool and you'll get a graph. It's nothing to do with your actual heartrate though and it's not meaningful.  

[Coloradodaisy]

So this is confusing, but thank you, also. I am still learning that actual purpose of this device. I am concluding that it is really a training diary on my wrist--with limitations in its record-keeping just as a human might make mistakes. It records heart rate, but with errors. It automatically identifies and records exercise, but also misses workouts. It says it can do something (like record swimming), but doesn't do such a good job. It seems to over-count steps in my house, so I am suspicious of other counts. At least it gives patterns and history, which are useful. I will learn to adjust for errors. 

It totally missed my swimming workout when I expected it to auto record. I figured it was because of my low pulse. Must be because of my bad technique? Same thing with my walks and hikes. I will need to pay better attention to the settings I am working with, but it doesn't seem to consistently pick up exercise sessions that it claims to have the ability to sense.

Bottom line I am still in the learning stage. It is very helpful. thanks for following me @alexthecat 

[alexthecat]

@Coloradodaisy  Fitbit trackers use a technology called photoplethysmography (PPG) to measure heart rate. PPG works by shining a light through your skin and measuring how much light is absorbed. When your heart beats, more blood flows through your veins, which absorbs more light. 

Water interferes with that measurement and prevents accurate heartrate detection. That is why you cannot get an accurate heartrate measurement when swimming. This is true of all wrist-based trackers that use optical heartrate detection. 

You can learn more about using your Fitbit to monitor heartrate, including tips for improving accuracy, here.

The automatic detection of activities is not related to you heartrate. Your Fitbit recongizes the repetitive motion of your arms as being consistent with that of a particular exercise. I find it better to start exercise sessions on my Fitbit, rather than relying on the device to recognize the activity and assign the Start and Stop times correctly.