Exercise mode

Why isn't Exercise mode available in the standard AAPS when using autoISF?

Exercise mode was intentionally disabled in AAPS several years ago due to associated risks. However, in the current configuration, it is enabled, mirroring the approach in OpenAPS. While Exercise mode can be a potent tool, caution is advised in its use. Scott Leibrandt outlined the risks, emphasizing their rarity. These risks only manifest under specific conditions, all of which must be met simultaneously:

1. Oref1 sensitivity is enabled.
2. High temptarget raises sensitivity is enabled.
3. A site change or profile change has been logged within the last few minutes.
4. A high temptarget is enabled.
5. An unreasonable autosens threshold has been set.

(Note: Point 5 serves as a safety setting, requiring intentional modification from default settings.)

A toggle has been incorporated into the overview screen for swift activation (bottom) or deactivation (top) of the exercise mode. Alternatively, users can customize settings individually within the OpenAPS SMB menu. The pertinent settings for the exercise mode include:

• The parameter high_temp_target_raises_sensitivity (synonymous with "exercise mode") is set to false by default. When configured as true, it increases sensitivity (decreasing sensitivity ratio/ISF numbers) and decreases basal rates when the temp targets surpass 100. The greater the deviation of your temp target above 100, the more pronounced the impact on sensitivity ratios. For instance, a temp target of 120 yields a sensitivity ratio of 0.75, while a target of 140 results in a ratio of 0.6 (assuming the default half_basal_exercise_target is 160). Basal rates will be proportionately reduced. Refer to half_basal_exercise_target for additional details.

• half_basal_exercise_target defaults to 160 mg/dl. This implies that when the temporary target is set to 160 mg/dl, and high_temptarget_raises_sensitivity is true, the system will adjust the basal rate to 50% (for a temp target of 120 at 75%; for a temp target of 140 at 60%). You have the flexibility to customize this base exercise target number in the OpenAPS SMB menu, providing you with more precise control over your exercise modes. Notably, this adjustment not only affects the basal rate but also influences sensitivity. Refer to the documentation on high_temptarget_raises_sensitivity for further details.

• low_temp_target_lowers_sensitivity is a boolean parameter, with a default value of false. When set to true, it has the capability to reduce sensitivity, thereby increasing the sensitivity ratio or ISF (Insulin Sensitivity Factor) numbers for temp targets below 100. As the temp target drops below 100, the sensitivity ratios become less responsive. For instance, a temp target of 95 yields a sensitivity ratio of 1.09, whereas a target of 85 results in a ratio of 1.33 (assuming the default value for half_basal_exercise_target is 160).

• It's important to note that this adjustment not only affects sensitivity ratios but also results in corresponding adjustments and increases in basal rates.

NOTE

Kindly be aware that the sensitivity ratio (ISF), as adjusted according to the exercise mode, serves as the foundational factor for subsequent sensitivity modifications via autoISF. This represents an extension of the fundamental principle, wherein only the more potent ISF modifier takes precedence.