Impact of Fitness on Type 1 Diabetes Management: a. Blood Sugar Control:
Regular exercise improves insulin sensitivity and enhances the body’s ability to utilize insulin effectively.
Physical activity helps to lower blood sugar levels during and after exercise by increasing glucose uptake by muscles.
It can reduce the amount of insulin needed for glucose management.
b. Glycemic Stability:
Engaging in regular physical activity helps promote more stable blood sugar levels throughout the day.
Consistent exercise routines can lead to better overall glycemic control and reduce the frequency of extreme highs and lows in blood sugar levels.
c. Cardiovascular Health:
Type 1 diabetes increases the risk of cardiovascular complications. Regular exercise can mitigate this risk by improving cardiovascular health.
Aerobic activities like walking, jogging, or cycling help strengthen the heart, lower blood pressure, and improve overall cardiovascular fitness.
d. Weight Management:
Maintaining a healthy weight is important for individuals with type 1 diabetes, as excess weight can make blood sugar management more challenging.
Regular physical activity helps manage weight by burning calories, building lean muscle mass, and improving metabolic function.
e. Mental Health and Well-being:
Regular exercise has a positive impact on mental health and overall well-being, which is crucial for individuals managing a chronic condition like type 1 diabetes.
Physical activity releases endorphins, reducing stress, anxiety, and depression often associated with diabetes management.
Key Factors to Consider: a. Blood Sugar Monitoring:
Before, during, and after exercise, individuals with type 1 diabetes should regularly monitor their blood sugar levels to ensure they remain within a safe range.
Blood sugar levels may fluctuate during exercise, so it is essential to be prepared to adjust insulin dosages or carbohydrate intake accordingly.
b. Individualized Approach:
The impact of exercise on blood sugar levels can vary from person to person.
It is important for individuals with type 1 diabetes to work closely with their healthcare team to develop an exercise plan tailored to their specific needs, taking into account factors such as insulin regimens, meal timing, and personal fitness goals.
c. Hypoglycemia Prevention:
Exercise can sometimes cause hypoglycemia (low blood sugar) in individuals with type 1 diabetes.
Proper planning is crucial to prevent hypoglycemia during or after physical activity.
Adjustments in insulin dosages, meal/snack timing, and carbohydrate intake may be necessary to maintain blood sugar stability.
d. Hydration and Recovery:
Staying adequately hydrated before, during, and after exercise is important for individuals with type 1 diabetes to maintain overall health and prevent dehydration-related complications.
Proper recovery, including rest, nutrition, and adequate sleep, is crucial for optimizing the benefits of exercise and managing blood sugar levels effectively.
Conclusion: Fitness plays a significant role in the management of type 1 diabetes. Regular exercise can improve blood sugar control, promote glycemic stability, enhance cardiovascular health, support weight management, and positively impact mental well-being. It is essential for individuals with type 1 diabetes to work closely with their healthcare team, monitor blood sugar levels, and tailor their exercise routines to their specific needs to ensure safe and effective diabetes management.
Introduction: Fitness tracking has become an integral part of the modern fitness journey, helping individuals understand their progress, set goals, and optimize their training. Two popular platforms, Garmin and Strava, offer unique fitness metrics that provide insights into an individual’s performance and progress. In this blog post, we will delve into the science behind Garmin’s fitness metrics (VO2max, fitness age, training status, stamina) and compare them to Strava’s Fitness and Freshness metrics, shedding light on their differences and applications.
Garmin Fitness Metrics:
VO2max: Garmin’s VO2max is a well-known fitness metric that measures the maximum amount of oxygen an individual can consume during intense exercise. It is considered one of the most accurate indicators of aerobic fitness. The calculation takes into account factors such as heart rate, speed, elevation, and personal characteristics. The higher the VO2max, the better the cardiovascular fitness level.
Fitness Age: Garmin’s Fitness Age metric estimates an individual’s fitness level compared to the general population. It considers various parameters such as activity level, body composition, resting heart rate, and VO2max. By comparing these factors with an average person’s data, Garmin determines an individual’s fitness age. If your fitness age is lower than your actual age, it suggests a higher fitness level.
Training Status: Garmin’s Training Status provides real-time feedback on the effectiveness of your training program. It considers your recent exercise history, performance indicators, and physiological data to determine whether you are undertraining, maintaining, or overreaching. This helps individuals optimize their training by finding the right balance between intensity, volume, and recovery.
Stamina: Garmin’s Stamina metric helps gauge an individual’s energy levels during long-duration activities. It takes into account factors like heart rate, intensity, and duration to estimate the remaining time until exhaustion. Stamina provides valuable insights for endurance athletes, helping them understand their capabilities and manage their efforts during extended activities.
Strava Fitness Metrics:
Fitness: Strava’s Fitness metric focuses on an individual’s overall fitness level and is derived from analyzing their training load and intensity. By taking into account factors like distance, duration, and heart rate, Strava calculates a Fitness score. The higher the score, the better the overall fitness level. It provides a general indication of an individual’s current state of fitness.
Freshness: Strava’s Freshness metric complements the Fitness score by considering an individual’s recent training history. It evaluates the balance between training load and recovery, providing insights into the individual’s readiness for further intense training. A higher Freshness score suggests a well-recovered state, enabling athletes to plan their training schedule effectively.
Comparing Garmin and Strava Metrics:
While both Garmin and Strava offer valuable fitness metrics, there are some key differences between them. Garmin’s metrics, such as VO2max, fitness age, training status, and stamina, provide a more detailed analysis of an individual’s physiological parameters. They focus on factors like oxygen consumption, heart rate, and personalized data to provide a comprehensive view of fitness and performance.
On the other hand, Strava’s Fitness and Freshness metrics are more straightforward, providing a quick overview of an individual’s overall fitness level and recovery status. They are based on training load, intensity, and recent training history, offering insights into an individual’s readiness for further training.
The following table compares the key Garmin and Strava fitness metrics:
Metric
Garmin
Strava
VO2 max
Estimates the maximum amount of oxygen your body can use during exercise.
Not available.
Fitness age
Estimates your fitness level relative to your age.
Estimates your overall fitness level based on your activity history.
Training status
Indicates whether you are in a training, overtraining, or undertraining state.
Not available.
Stamina
Estimates your ability to sustain long-term exercise.
Not available.
Freshness
Estimates your recovery status based on your recent activity and sleep data.
Estimates your recovery status based on your recent activity and sleep data.
Conclusion:
Garmin and Strava, both renowned fitness platforms, offer distinct fitness metrics that cater to different aspects of training and performance. Garmin’s metrics, such as VO2max, fitness age, training status, and stamina, provide a deeper understanding of an individual’s physiological parameters. Strava’s Fitness and Freshness metrics, on the other hand, focus on overall fitness level and recovery status. By utilizing these metrics, individuals can optimize their training programs, set realistic goals, and monitor their progress effectively, ultimately enhancing their fitness journey.
Week 10 is done and dusted. During my long run on Friday I decided to use the New Balance Fresh Foam More V3 running shoes to see if that improved my experience. This is because they are the most padded shoes I own, and the small 3 mm drop is supposed to reduce the risk of injury. Unfortunately this only reduced the pins and needles, but I must have laced them poorly as I got a few blisters. I also started my run way to quickly, and if I cant maintain a few zone 2 runs I am not going to work my slow twitch muscle fibers and improve my fitness fast enough to enjoy this race. These were shoes I had used before so I think it was down to the lacing and running technique. The last run of the week was a 8 km zone 2 run on the treadmill. This was actually the first of run week 9, but I decided to mountain bike ride on the Monday as it was raining on the Sunday so I switched them. For this run I used the New Balance 1080v12 shoes, and this was a great run. Not sure if it was due to treadmill suspension but every second felt good, despise a hypo half way though.
Exercise stats
Blood glucose stats
My experience with AIMI AI has not been a good one, for some reason I keep going on the blood sugar roller coaster and the system either gives too much or too little insulin. I am eating way less at the moment so I would expect more control. I’m back to Boost once this Pod expires to try and improve my glucose values. Probably not a great time to be trying a new system while increasing my training.
Measurements
Weight 75.6 kg
Week 9 (01st – 07th)
In an attempt to reduce the pins and needles I was experiencing I got some 2XU vector compression socks. This seemed like it may have improved the experience somewhat, until I started wearing my Brooks Ghost shoes. During the 8km run with the Ghosts I experienced no issues whatsoever. Blood sugars with AIMI seemed to be much better this week, except for a few isolated incidences where AIMI provided too much insulin. Since AI (or in this instance machine learning) requires data to build its model accurately, its seems likely that I needed more data in order for the system to perform better.
Exercise stats
Blood glucose stats
AIMI – ModelAI
Measurements
Week 8 (08th – 14th)
This week was was a big training week with the start of the extended distance (15-20 km) runs in the training plan. I have bee using the Ghosts more and although I no pain during my runs, I had quite a few blisters afterward the 15 km run. No vector socks this week. The long run was a little difficult to manage with my sugars requiring (22g+25g+28g) 75 g of carbs to stabilize for the run. I wasn’t expecting that. Quite a few more hypers that lasted longer than I had hoped. I think this is my last week of testing AIMI-AI before heading back to good old Boost. I like the fact I can very accurate with IOB with Boost, although my difficulty is due to AIMI adapting so well with all the changes. I also found myself on my Strava groups leader board twice 🙂
Its been interesting to see the difference between how Garmin and Strava track fitness, with Garmin using Vo2 max as its measurement and providing a stamina metric.
Exercise stats
Fitness
Below is a post highlighting the difference between the two systems in relation to fitness metrics.
The Strava fitness metric seems to build with every run, providing some motivation to keep hitting those zone 2 runs. I am still 10 fitness points lower than I was in December. I am currently averaging 6 points every two weeks. If keep at this pace I should reclaim my fitness in about 23 days, or by the 6th of June. So that leaves almost the whole of June to work on improving fitness.
Garmin fitness metrics
The Garmin fitness metric is Vo2 max, or maximal oxygen consumption. This refers to the maximum amount of oxygen that an individual can utilize during intense or maximal exercise. This measurement is generally considered the best indicator of cardiovascular fitness and aerobic endurance.
Blood glucose stats
AIMI – ModelAI
Measurements
Week 7
This week I decided to shake things up, do a little mountain biking in New South Wales and also travel to new beach locations for my runs. It was amazing and I had an incredible time. I have also been asked to be a front runner for the Gold Coast Marathon team training sessions at HOTA.
Exercise stats
Blood glucose stats
AIMI – ModelAI
Measurements
Week 6
This weeks long run was a little harder than usual, but it did have a beautiful view. I wanted to do a 15km but unfortunately was cut short to 14km. My feet felt good and good issues with blistering with the Ghosts. I also did a park run which almost ruined everything as my tendon issue faired up with the lack of a proper warm up. I was a little slower than I thought as I only managed 5min/km for 2,5km before burning out.
Exercise stats
Blood glucose stats
AIMI – ModelAI
Measurements
74kgs
Week 5
This week’s long run was fantastic! I completed the full 16 km without experiencing any pain or discomfort. As an experiment, I decided to try a Cliff Bar for the first time during my run, and I think I may have found my new go-to snack for long-distance running. I started my run with a blood glucose level of 4.1 mmol/l and waited approximately 20 minutes after consuming the bar before getting started. This slight delay caused a small spike in my glucose levels at the beginning of the run. To mitigate this, I plan to wait only 15 minutes before starting my next run.
Analyzing the graph below, we can observe when the Automated Insulin Delivery Systems (AAPS) kicked in to provide a temporary basal rate adjustment to lower my blood sugar levels. Since I set a slightly higher temporary target of 8.3 mmol/l, AAPS registered my insulin sensitivity to be around 55% less than my standard needs. AAPS responded perfectly, gradually bringing my glucose levels down to a comfortable 5.2 mmol/l by the end of the run.
Overall, this run was a success, and the combination of the Cliff Bar and the effective response of AAPS made it even better. I’m excited to continue fine-tuning my routine and exploring the benefits of different strategies to optimize my long-distance running experiences.
Exercise stats
Blood glucose stats
AAPS – Boost 3.9
Measurements
74 kgs
Week 4
This week was a bit of a mixed bag for me as far as my diabetes management goes. On the one hand, I had a great park run, where I managed to run a respectable 5:10 min/km for the 5km duration. This landed me in second position overall for this particular park run.
My long run started off very strong, but towards the end I developed some pain in the glute which resulted in me needing to stop the run at 17km, rather than the planned 18km. I managed to stay in range 100% (3.9-7.8 mmol/l) for the duration of the run with an average of 5.8 mmol/l, and my standard deviation was 1.024. I attribute to this to the cliff bar I ate 15min prior to starting the run.
I had a high percentage of low blood glucose readings on my CGM this week, which was mainly due to CGM sensor issues. This, in conjunction with poor rest has resulted in my HRV being quite for low for the week.
I went one full work week without sugar free soda. This change was due to recent research released indicating the significant detriment to health sugar free soda can have.
Exercise stats
Blood glucose stats
AAPS – Boost 3.9
Measurements
Week 3 (12-18th)
Exercise stats
Blood glucose stats
Measurements
Week 2
During my last long run, I had to make the difficult decision to bail out early. Unfortunately, I was dealing with an ankle and tendon injury, which limited my capacity to cover the desired distance. Additionally, my blood sugar levels dropped significantly, adding another layer of challenge. Upon reflection, I realized that this low blood sugar episode was a consequence of inadequate planning. I had not set a high enough temporary target of 8.3 for a sufficient duration, leading to the drop in blood sugar levels.
To alleviate some stiffness in my legs, I sought a massage on Sunday. However, this revealed another issue – lower back pain on the left side. It became evident that this discomfort was likely a consequence of my existing tendon problem on the left side, as my body attempted to compensate for the imbalance. While I have been diligent in incorporating stretching exercises into my routine, it is unfortunate that I began doing so too late to make a significant impact on my current situation.
Despite the challenges I have faced, I consider these setbacks as valuable learning opportunities. Moving forward, I intend to implement the following lessons to prevent similar situations:
Prioritize Injury Prevention: Understanding the importance of injury prevention, I will be more cautious with my training and listen to my body’s signals. This means recognizing the need for adequate rest, seeking professional advice when necessary, and gradually increasing intensity and distance.
Establish Effective Blood Sugar Management: To avoid experiencing low blood sugar levels during physical activities, I will proactively set higher temporary targets and ensure their duration aligns with the demands of my workouts. This way, I can maintain stable energy levels and perform optimally.
Address Imbalances and Compensatory Patterns: By acknowledging the connection between my tendon issue and the resulting lower back pain, I will incorporate exercises and therapies that specifically target these areas. By addressing imbalances early on, I can prevent further complications and improve overall performance.
While my fitness has undeniably declined due to the limitations imposed by my injuries, I have gained valuable insights from these experiences. By emphasizing injury prevention, refining blood sugar management, and addressing compensatory patterns, I am confident in my ability to overcome these setbacks and continue progressing on my fitness journey. Remember, setbacks are not roadblocks but opportunities for growth and resilience.
Exercise stats
Blood glucose stats
Measurements
Week 1
The lead up to race week has been less than ideal. Unfortunately my injury is preventing me from training and is causing pain and discomfort when I run, especially at incline. This was a reminder that injury prevention is key, and if I ever attempt this again I will ensure I follow a program that prioritises injury prevention through intelligent training, gradually increasing mileage and strength training. Please read my retailed post about the race below.
It’s been three weeks since my last post on the half marathon goal for 2023. I had set myself a target of being able to run 10 km by the 28th of April in order to commit to the 21 km run. So far its undecided as I seem to keep getting a numb right foot during runs, although my fitness seems like its returning slowly.
Blood glucose Analysis for the last three weeks:
During this time I was using a dev branch of AAPS with automations to scale the insulin requirements.
Exercise analysis for the three weeks:
The last week was the start of my running ramp-up increasing distance more substantially from 3-4 km to 6-7 km.
Unfortunately I have been plagued by a numb right foot as I exceed the four (4) km distance. This prompted me to do a little research and the most common problem found seemed to be shoes that did not fit well, or that were laced too tightly.
This could of course be glucose related (neuropathy), as when my A1C was in the sevens (7) I experienced something similar, but It seemed to start as I laced up.
Today’s run I changed shoes to see if that helped, unfortunately I still experience the numbness quite early on in the run, but I kept going. At around the seven (7) km mark I decided to increase pace and this seemed to remedy the issue strangely. Below is a graph of the 9 km run from AAPS / Nightscout data using my custom Python scripts.
The next steps are to purchase some Omega 3 and Alpha lipoic acid and ascertain if that can assist with the foot pain.
It’s been a long-standing goal of mine to run a half marathon. It’s long enough to be a challenge, and short enough that I don’t need to be training all year round and can focus on my other sports.
Pre-requisites
Basal review – I will be doing an incremental basal review in the next few days (hopefully). Skipping meals where required.
Full profile review – Once the basal profile has been updated, I will check my CR (carb ratio) and CRR (carb rise ratio). No need to check ISF (insulin sensitivity factor) as its calculated in Android APS. I will need to be on the look out for blood sugar dips two or more hours after meals as I may need to reduce the Dynamic ISF Adjustment factor.
Injuries
At the moment I have an Achilles tendon issue I am in rehabilitating. It’s the first time I am experiencing this issue, so I am working with a Physio to remedy it.
Training Program
I plan on using the Garmin training program to do most of my training. My longest run prior to this was 16 km and I mountain bike so I think I may be ok with fitness if I can get back into training fairly quickly, but this is dependent on how well my current rehab program works.
This will be updated as and when I can, but the next 3 three (3) weeks are as follows:
Tendon Rehab Program:
Week
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
1
Calf raise holds 5 x 45 seconds, Gym
3km run, double leg calf raise x 3 12-15, body weight single leg calf raise 3 x 10-15
Calf raise holds 5 x 45 seconds, Gym
Calf raise holds 5 x 45 seconds, Gym
3km run in AM, double leg calf raise x 3 12-15, body weight single leg calf raise 3 x 10-15
Calf raise holds 5 x 45 seconds, Gym
Bike in AM
2
Calf raise holds 5 x 45 seconds, Gym
4-5 km
Calf raise holds 5 x 45 seconds, Gym
Calf raise holds 5 x 45 seconds, Gym
4-5 km
Calf raise holds 5 x 45 seconds, Gym
Bike in AM
3
Calf raise holds 5 x 45 seconds, Gym
5-7km
Calf raise holds 5 x 45 seconds, Gym
Calf raise holds 5 x 45 seconds, Gym
5-7km
Calf raise holds 5 x 45 seconds, Gym
Bike in AM
NOTES: If pain/stiffness gets progressively worse, then reduce load and re-assess. If not monitor and keep working.
Strava Running Program:
I had really wanted to use the Garmin program, but I was too late to start it. The Strava program doesn’t seem to have the ability to select the days I plan on running or feedback on training progress at a granular level. My desired routine is 3 days per week.
Garmin Running:
Global Triathlon Network (GTN) half marathon training program
I really liked the plan from GTN, I have modified it a little to fit within my availability.
Disclaimer: The information contained within this blog post are my thoughts and do not constitute medical advice. Please consult your medical team before making any changes to your diet or blood sugar management program.
So far 2022 has been quite the year. With the return to my work offices Its been rather difficult to reach many of the goals I set myself, but I did make progress. It seems 2023 is set to be a particular difficult year, but perhaps this will be the inspiration I need to make some positive changes. The Python scripts I wrote to export data from Nightscout to create my mountain bike videos seem to be working well and I can’t wait to make a few more videos.
I was curious to see if there were any differences in insulin sensitivity between longer and shorter activity durations, as well as higher intensity (where average heart rate was more than 80% of max heart rate) training and it seemed there was, it just wasn’t what I was expecting.
My average total daily dose (TDD) for 2022 was 32.9 units per day. If we analyse my aerobic activity (ride and runs) for the year and we use my sensitivity ratio from AAPS for 24 hours post exercise, I calculate that I saved 256 units of insulin in 2022 through exercise due to increased insulin sensitivity. During aerobic activity I consume 12g of carbs on average per 30 mins of activity unless I am exercising fasted. I can use this input to calculate that I ate 2277g of carbs during 2022. I would need 311 units of insulin to absorb 2277g of carbs. Since I don’t add carbs to AAPS while exercising I don’t have the exact numbers but I do believe this calculation to be pretty accurate. That equates to 49 Big Mac burgers / 82 Apples / 73 slices of Dominos peperoni pizza that I got to eat without insulin as a direct result of exercise.
Exercise metrics
Analysing my exercise metrics I found that I was spending way too much time exercising at more than 75% of heart rate max, this would be hampering performance and building endurance. I did eighteen (18) runs at a distance greater than 8km, an improvement over the two (2) I did in 2021. I also managed my longest run ever at 16km.
exercise type
exercise count
total distance (km)
average distance (km)
average moving time (minutes)
average heart rate (bpm)
EBikeRide
7
20.64
2.95
18.65
N/A
EBikeRide ( > 8 km)
17
252.4
15.7
59.4
133.8 (72% max HR)
Run
108
374.25
3.47
23.5
139.26 (75% max HR)
Run ( > 8 km)
18
183.1
10.1
67
156 (85% max HR)
Walk
48
65.8
1.37
18.6
93 (50% max HR)
WeightTraining
65
0.0
0
33.77
105 (57% max HR)
TOTAL
262
896
5.6
36
125 (68% max HR)
Exercise stats table for 2022
Time-in-range (TIR)
The longer distance running seem to result in the best time-in-range (TIR) (3.9-7.8 mmol/l) but I do feel that these runs also seem to happen at a similar time in the morning where I have more control over insulin-on-board (IOB) and carbs-on-board (COB) and I am the most resistant to insulin. My heart rate is also far more consistent (aerobic) during running than when mountain biking ( aerobic / anaerobic ).
If I start digging into the data for short runs more closely I find that;
TIR (3.9-7.8 mmol/l) from 04:00am – 10:00am is 63%
TIR (3.9-7.8 mmol/l) from 10:00am – 13:00pm is 83%
TIR (3.9-7.8 mmol/l) after 13:00pm is only 23%
exercise type
exercise count
time-in-range (%)
EBikeRide
7
81.67
EBikeRide ( > 8 km)
16
65.56
Run
108
56.8
Run (04:00 – 10:00 am)
18
63.8
Run (10:00 – 13:00 pm)
61
83.6
Run (13:00 – 10:00pm)
29
23.02
Run ( > 8 km)
18
93.6
Walk
45
75.8
WeightTraining
65
87.7
Exercise time-in-range table for 2022
Blood glucose control metrics
The exercise that resulted in the lowest blood glucose fluctuations is walking with a CV of 4%. The exercise with the second lowest CS was weight training. I generally try to train with a little insulin-on-board to counteract the hormones released during training and I don’t need to set a high temp target in the lead-up to the activity, thus my reading is much lower at exercise commencement. The third lowest is short runs (< 8km) with CV of 6%. The higher blood glucose average will be a direct result of me setting a higher temp target (8 mmol/l) prior to exercising, but the duration of activity isn’t long enough to reduce the blood glucose substantially resulting in the high average. Long runs seem to result in the least stable blood glucose values with a CV of 12% but the average for long runs is lower as the sustained activity reduces blood glucose. I suppose on these longer runs I do consume a minimum of 30g of ultra-fast acting carbs (glucose, dextrose) which is going to result in some fluctuations in blood glucose.
With coefficient of the variation (CV) a lower percentage is indicative of more stable blood glucose readings.
exercise type
exercise count
average standard deviation
average blood glucose
average coefficient of the variation (CV)
EBikeRide
7
0.57
7.49
8%
EBikeRide ( > 8 km)
16
0.92
10.6
9%
Run
108
0.43
7.19
6%
Run ( > 8 km)
18
0.69
6.24
11%
Walk
48
0.27
6.77
4%
WeightTraining
65
0.4
6.39
6%
Exercise breakdown for 2022
Insulin sensitivity
A very interesting observation was that longer, more intense activity resulted in sensitivity returning to normal quicker than less intense or shorter activity. Runs shorter than 8km resulted in a massive 12% insulin reduction for 24 hours post activity, that’s around 6.5 units less insulin in a 24 hour period. Long E-Bike rides resulted in the largest increase (35%) in sensitivity 1 hour post activity, with shorter E-Bike rides the second largest increase in sensitivity. Runs longer than 8 km increased sensitivity (25%) the third most, but the body seemed to return to normal more quickly than the shorter runs and was almost back to normal within 12 hours of activity.
(NOTE: I can’t comment on the validity of the results, only that patterns exist after exercise that are not usually observed in the absence of aforementioned exercise.)
average insulin sensitivity
exercise type
exercise count
1 hr post exercise
3 hr post exercise
6 hr post exercise
8 hr post exercise
12 hr post exercise
24 hr post exercise
EBikeRide
7
109
105
103
102
99
95
EBikeRide ( > 8 km)
16
68
78
88
93
97
79
Run
108
86
92
95
96
102
98
Run ( > 8 km)
18
76
80
92
94
97
94
Walk
48
105
109
111
112
114
109
WeightTraining
65
95
101
100
106
110
104
Average insulin sensitivity for multiple time blocks post exercise grouped by exercise type.
Profile Adjustments vs. Temporary Targets (TT)
In the past I used a combination of a 30% reduction in profile and a temporary target of 7 mmol/l while exercising.
This seemed to work quite well, with the caveat that profile adjustments can result in your autosens data being reset if you cancel the adjustment earlier than set.
One way to combat this is to set a higher temp target, this will not effect sensitivity data and can be cancelled at any time without needing to update the basal insulin profile in the pump of effecting autosense data. In order to do this I analysed the adjustments I was using to calculate a temp target that should reduce my insulin enough to keep me in range for the duration of activity.
It’s diabetes awareness month and so I wanted to talk to you about something I am very passionate about, Android artificial pancreas system (AAPS). It’s not the cure I wanted but as far as I am concerned, it’s the closest to normal I have felt in the 25 years I have been a diabetic.
Why ILOVEAndroid APS
I decided to try Android APS just prior to the birth of my daughter. At the time I was using multiple daily injections (MDI) on a low-carb diet (less than 45g per day excluding protein and fat) and trying to pick up some muscle. I found it rather challenging to eat the number of carbs the trainer suggested without compromising control. I was also anticipating the late nights having a baby entails and I wanted to be prepared. David Burren’s blog provided a blueprint of what could be expected if I committed to investing the time required to perform all necessary testing and fine-tuning.
Benefits of Android APS
Meal management
Meals can be managed through a number of mechanisms including;
Un-announced meals (UAM) – AAPS boluses insulin without intervention or carb entry.
Announcing carbs – Add the carbs into the system and the calculator estimates the amount of insulin required based on your COB, IOB, ISF, current blood glucose, blood glucose deltas, and insulin sensitivity.
Extended carbs – typically used to mimic the absorption of protein (gluconeogenesis) or delayed gastric emptying caused by high-fat meals.
Exercise management
Insulin scaling adjusts basal insulin based on current insulin sensitivity
Automations allow you to schedule profile changes and temporary blood sugar targets for the duration of activity or condition.
Directly or indirectly (via Nightscout) display various blood glucose-related data on compatible watches. If you are using an Android watch (WearOS) you can control AAPS via the watch. Garmin watches can display blood glucose data during an activity.
Utilise the blood glucose data from a wide variety of CGMs (continuous glucose monitors)
Software
Automations allow you to automate system actions based on conditions (eg. blood glucose increasing, blood glucose decreasing, leaving for work, pump disconnect) or schedules.
Highly customizable to your unique needs, with certain advanced builds allowing you to control more system variables (Boost, AIMI, Eating Now).
Cutting-edge development
Dynamic insulin sensitivity factor (ISF that changes based on blood glucose)
Improved prediction models
Improved insulin modeling (9-hour DIA)
Quality of Life
Reduced diabetic burden and stress.
Glucose is constantly monitored, with the ability for someone to follow you remotely, including community members. This can assist with fine-tuning settings.
Ability to eat more foods without compromising control
Improved glucose control reduces the possibility of long-term complications.
Safety
Objectives provide a level of safety as users need to understand basic principles of how to use the APS prior to closing the loop.
Nightscout reporter provides detailed reports that can assist with APS tuning and a detailed view of your risk rate through the comprehensive glucose pentagon.
As with all DIY systems, you are required to build the application prior to using it.
Cost of hardware
Phone
CGM
Pump and supplies
Connectivity fatigue
The burden of being connected to technology 24/7
Reliance
It is easy to become reliant on AAPS managing blood sugars.
Usability
Due to its complexity, you are required to invest a large amount of time in order to gain the understanding and skills required to configure and utilise it correctly.
Statistics and examples:
Nightscout statistics – 3 Months
Nightscout blood glucose distribution reportNightscout blood glucose weekly distribution report
Control stats for different systems
Date Started Test
Control Mechanism
e-A1C
Average Blood Glucose
Time In Range (TIR) 3.9 – 10
Standard Deviation
Average carbs consumed
GVI
PGS
CGP – PGR
20/11/2019
MDI
6.1%
7 mmol/l
87%
2.2 mmol/l
1.2
20.33
1.7
20/11/2020
MDI
5.6%
6.3 mmol/l
94%
1.7 mmol/l
< 60
1.17
8.67
1.3
20/11/2021
Loop
5.7%
6.5 mmol/l
94%
1.7 mmol/l
<100 (carb counting)
1.25
8.29
1.3
04/02/2022
Android APS
5.7%
6.5 mmol/l
96%
1.5 mmol/l
>200, little to no carb counting
1.24
5.70
1.2
Analysis stats provided by Nightscout reporter.
Comprehensive glucose pentagon from Nightscout reporter report.
Un-announced meal (UAM) example
Low-carb meal with UAM running (Low-carb bread with cheese, ham, and mayo.)
Extract from Android APS data for a low carb meal
As can be seen above the system manages low-carb meals quite well with no carb inputs from the user. The system constantly monitors for rapid changes in blood sugars and administers insulin when required to quickly brings sugars into range.
Nightscout screenshot of low carb meal being absorbed while AAPS manages sugars.
Exercise stats / examples
Year
Average Time in Range (3.9-7.8 mmol/l)
Average blood glucose (mmol/l)
Average Standard Deviation (mmol/l)
Total Hours
Total KM
2022
80.1 %
6.6
0.43
131
885
2021
71.9 %
6.7
0.4
149
920
2020
69.7 %
6.9
0.7
67
658
Annual improvements are made through tweaking system variables and my approach to exercise.
Weight Training
Date
IOB @ start
Moving time
Exercise Type
Average HR (bpm)
Standard Deviation (mmol/l)
CGM BG Start
CGM BG End
CGM BG Average (mmol/l)
TIR (3.9-10)
2022-10-07
0.14
36.93
WeightTraining
101.1
0.365
7.7
6.8
7.27
100.0%
EBike Ride
Android APS data exported during an E-Bike Ride 2022-11-06.
Date
IOB @ start
Moving time
Exercise Type
Distance (km)
Average HR (bpm)
Standard Deviation (mmol\l)
CGM BG Start
CGM BG End
CGM BG Average (mmol\)
TIR (3.9-10)
2022-11-06
-0.849
115.92
eBikeRide
27
143
1.095
5.9
5.8
7.16
100%
Running
Android APS data exported during a run 2022-10-03.
This week was the best so far. I did my longest run to date (12km) and had a really good gym week lifting (approx. 20% more volume). My diabetes control is improving (thank you AAPS and exercise) and I have learned a lot digging though my data and through responses from the previous weeks question regarding carb sensitivity factor (CSF) being used to measure insulin sensitivity post exercise. I made some strides in my glucose management tool which also felt great.
BG vs. ISF vs. insulin sensitivity post gym (@11:48:09 – 42min)BG vs. ISF vs. insulin sensitivity post run (@11:49:30 – 33min)
After gym sensitivity increased to 115% directly post training, while my sensitivity was stable at 78% post my run.
Body Metrics
Body mass vs. body fat
Start
Week 1
Week 2
Week 3
Week 4
Weight (kilograms)
75.8
74
75
74.1
73.1
Body fat percentage (according to Samsung)
17.3%
17.8
*
*
Body fat percentage (according to the navy seal calculator)
15%
15%
14.8%
14%
Total volume
Table stating the weekly body metrics I am tracking.
Exercise
Week 1
Week 2
Week 3
Week 4
Distance (kilometres)
25.17
20.54
37.22
29.4
Activity (hours)
4.34
3.65
5.64
5.4
Table stating the weekly exercise metrics I am tracking
Nutrition
Screenshot of average macro-nutrients consumed during week 4
Screenshot of average macro-nutrients consumed during week 4
Diabetes
Week 1
Week 2
Week 3
Week 4
Low (<3.9) (%)
0.9
0.6
3.5
1.6
In Range (3.9-7.8) (%)
75.3
74.7
71.9
78.9
High (>= 7.8) (%)
23.8
24.7
24.6
19.5
Standard deviation (SD)
1.3
1.7
1.7
1.5
Average (mmol/l)
6.8
7.0
6.7
6.5
A1c estimation (%)
5.9
6.0
5.8
5.7
Table stating the weekly diabetic metrics I am tracking.
Ideally I want to see a time-in-range (TIR – 3.9-7.8 mmol/l) exceeding 90% with an average in the low sixes and a standard deviation (SD) around one (1).
I am starting to feel like a routine is forming, perhaps not around diet yet, but definitely in regards to training. In previous years of doing this I was eating clean most days, as it provided improved diabetic control in the absence of an APS/AID and pump.
This week was particularly heavy due to my birthday dinner, a new phone, a new version of AAPS (Boost test platform 3.6.5) and a 25 km cycle. *I have been unable to pair my galaxy watch with my new phone, which is sad as I really liked the watch and having the plethora of sensors.
I was investigating the possibility of measuring insulin sensitivity changes in AAPS . One way would be to use the autosens feature in AAPS , but since I wasn’t including the carbs I ate to fix hypos, and I was snacking in-between to keep my readings steady that wasn’t going to work. The only metric that may prove useful may be my carb sensitivity factor (CSF). The average CSF over the 22 days so far is 8.7 while the average sensitivity ratio was 106%. This would mean that according to CSF I was 36% more sensitive to carbs yesterday or 29% less sensitive according to autosens.
Body Metrics
Start
Week 1
Week 2
Week 3
Week 4
Weight (kilograms)
75.8
74
75
74.1
Body fat percentage (according to Samsung)
17.3%
17.8
*
Body fat percentage (according to the navy seal calculator)
15%
15%
14.8%
Total volume
Table stating the weekly body metrics I am tracking.
Exercise
Week 1
Week 2
Week 3
Week 4
Distance (kilometres)
25.17
20.54
37.22
Activity (hours)
4.34
3.65
5.64
Table stating the weekly exercise metrics I am tracking
Nutrition
Screenshot of average macro-nutrients consumed during week 3
Screenshot of average macro-nutrients consumed during week 3
Diabetes
Week 1
Week 2
Week 3
Week 4
Low (<3.9) (%)
0.9
0.6
3.5
In Range (3.9-7.8) (%)
75.3
74.7
71.9
High (>= 7.8) (%)
23.8
24.7
24.6
Standard deviation (SD)
1.3
1.7
1.7
Average (mmol/l)
6.8
7.0
6.7
A1c estimation (%)
5.9
6.0
5.8
Table stating the weekly diabetic metrics I am tracking.
Ideally I want to see a time-in-range (TIR – 3.9-7.8 mmol/l) exceeding 90% with an average in the low sixes and a standard deviation (SD) around one (1).
Dick The Diabetic's APS Adventures 