The algorithm would then be expected to adjust insulin delivery solely based on changing glucose readings. On the other end of the spectrum, hybrid systems involve exercise announcement by the patient to the algorithm to adjust glucose target ranges higher targets and adopt a more cautious insulin delivery.

In between the two ends, trials include addition of glucagon in DH-AP, use of exercise detectors such as heart rate or movement to guide the algorithm to self-adjust or combinations of these approaches.

The aim behind investigating these different strategies is to account for exercise-induced: 1-increases in insulin sensitivity and absorption from subcutaneous depot due to skin heat and movement, 2- delays in CGM due to rapid changes in blood glucose levels 5 , 6.

As discussed in the previous sections, the effect on glucose of different types, duration, intensity and timing of exercise need to be taken into consideration when examining AP studies around physical activity 6. Good overall results were observed in a study conducted with unannounced 40 min exercise performed in a postprandial state as moderate and interval sessions in children and adolescents with T1D Median time of glucose-in-target 3.

standard insulin pump therapy; however, there were no differences in percentage of time in hypoglycemia ranges or in events requiring CHO replacement In another study, unannounced exercise to SH-AP algorithm was examined during prolonged skiing activity two sessions per day, 5 day camp in a group of adolescents and compared to another matched group under sensor augmented pump SAP control Although an overall benefit was seen with SH-AP vs.

SAP per 24 h and overnight for time spent with glucose-in-target, this was not maintained during the pooled skiing sessions and the hypoglycemia events requiring CHO correction Table 2 Table 2. Main artificial pancreas studies with reported exercise related outcomes.

These results support the use of a simple snacking strategy to avoid exercise-induced lowering of PG while on AP However, snack consumption may be undesired given the increased prevalence of the metabolic syndrome in patients with T1D who frequently practice exercise with in weight loss or maintenance objectives 3.

Other strategies to improve AP performance around physical activity consisted of examining the effect of glucagon addition through DH-AP systems and exercise announcement to the algorithm. Jacobs et al. tested if announcing physical activity to their DH-AP algorithm by adjusting its insulin and glucagon dosing at the start of a 45 min aerobic moderate intensity exercise could improve glucose management in the following hours Less time was spent in hypoglycemia with adjustment to DH-AP by 2.

The authors observed a similar time spent with glucose-in-target between the three arms Another head-to-head SH-AP to DH-AP comparison in which insulin dosing algorithm is similar in order to specifically investigate the additional benefit of glucagon incorporation in AP during exercise Two types of exercise sessions consisting of 60 min of continuous and interval exercise were performed in the postprandial state under both SH-AP and DH-AP on 4 separate visits Exercise was announced 20 min prior to its start which resulted in changing the target glucose level from 5.

Overall, with DH-AP, median time spent with glucose-in-target was increased by The number of hypoglycemia events requiring CHO treatment were also reduced 3 in DH-AP vs. An alternative to directly announcing exercise sessions to an AP algorithm was sought by some groups using exercise detectors such as heart rate monitors or accelerometers.

The idea behind exercise detection and indirect announcement is to relieve patients from active inputs especially during unplanned and unknown activity intensities.

Such systems would be particularly interesting to investigate in youngsters whose activity level is often unpredictable making them at high risk for both hypo- and hyperglycemia. Breton et al. were among the first to study the feasibility of adding heart rate monitoring to a SH-AP in 12 adults performing mild 30 min exercise sessions exhaustion at 9—10 on Borg scale Similar results were observed by Jacobs et al.

This triggered a change in glucose target from 6. A combination of different strategies was also tested. Recently, an interesting study was performed in adults comparing DH-AP and SH-AP that adapt to exercise using wearable sensors with predictive low glucose suspend and current care during and after exercise Both AP systems had an integrated algorithm for exercise detection that receives input from heart rate monitor and accelerometer the ZephyrLife BioPatch.

Once exercise was detected, the participant was asked by the algorithm to confirm it and the changes to insulin and glucagon were similar to what is described above for the study by Jacobs et al. Additionally the DH-AP was adaptive with adjustments to glucagon delivery at earlier timings and higher glucose levels on subsequent days 2—4 in comparison to day 1.

Number of hypoglycemia events requiring CHO consumption was also lowest with DH-AP over the whole study period with a mean of 0.

The AP studies that specifically tackled glucose control in relation to exercise are still heterogeneous, small in size and do not cover all exercise scenarios Table 2 summarizes the discussed trials. Most to date cover moderate intensity exercise performed in the post-absorptive state Table 2.

Nevertheless, they highlight the positive impact of artificial pancreas systems around exercise. AP is still an emerging technology and many future trials at large scale and in outpatient settings are needed in general and around exercise in particular. Directly announcing exercise seems to still be needed for optimized results but the timing of the announcement from the start of exercise maybe an area to explore in future studies particularly for postprandial exercise when meal insulin boluses are active.

Exercise detection by sensors is an interesting avenue particularly for children and adolescents living with T1D but adds the burden of wearing additional devices necessitating active research efforts in the future to develop small sensors integrated to the artificial pancreas itself.

Glucagon clearly shows an added benefit but the complexity of adding an additional chamber and material needs to be weighed against the additional hypoglycemia benefit.

Therefore, future research trails should be designed to carefully identify patients who are most in need of glucagon and show high rates of exercise-induced hypoglycemia.

While SH-AP currently reach the market in various countries, DH-AP are not expected to be commercialized in the near future since stable glucagon formulations are not yet available for use but promising research is underway.

Clinical trials with DH-AP may still be conducted with the commercially available glucagon used for severe hypoglycemia treatment but needs to be reconstituted every 24 h Meanwhile, another pressing aspect is proving the safety profile of chronic glucagon use in its different formulations or analogs given its multisystemic effects in humans Technological advances have endowed individuals with T1D with important tools to help them better manage their blood glucose during exercise mainly allowing more secure conditions with reduced hypoglycemia risks.

Some limitations to the different technologies have been detailed in this review and future research areas that need to be explored have been highlighted as well. The hope is that optimizing the use of these different technologies during exercise will encourage the majority of patients with T1D to regularly engage in physical activity.

ST, NT, and RR-L conceived the study design and content. ST and NT drafted the manuscript which was critically reviewed by RR-L. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

ST is supported by a fellowship grant from SFD Société Francophone du Diabète and FRM Fondation de Recherche Médicale. NT is recipient of scholarship of CIHR Canadian Institutes of Health Research and FRSQ Fonds de Recherche Santé Québec scholarships.

RR-L is holding the J-A DeSève diabetes research chair, a Diabetes Canada program grant DIRR and a NIH grant for artificial pancreas research that all supported this work. Chimen M, Kennedy A, Nirantharakumar K, Pang TT, Andrews R, Narendran P.

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Šoupal J, PetruŽelková L, Flekač M, Pelcl T, Matoulek M, Danková M, et al. Comparison of different treatment modalities for type 1 diabetes, including sensor-augmented insulin regimens, in 52 weeks of follow-up: a COMISAIR study. Non-invasive glucose monitoring promises blood testing without the need for even the small needle that CGM sensors use to measure glucose levels.

A leading concept in this space uses lasers to shine infrared light on the skin, delving beneath the skin surface to analyse the make-up of underlying tissue and sending this information back to a reader device.

Recent studies have shown that this technique can directly measure glucose concentrations through the skin, and the accuracy of the results have been refined to reach a level close to current CGM devices. The next step is including this in a useable wearable device, and there are plans to have a wristwatch type prototype ready in the next two years.

There are other challenges, such as how to ensure devices are calibrated and affordable, but non-invasive glucose monitoring also offers the opportunity to overcome some of the practical and environmental drawbacks of CGM by taking away the need for consumables.

If the technology can be incorporated into a wearable device, it may only need regular software updates to work and stay up-to-date. A company limited by guarantee registered in England and Wales with no. Skip to main navigation Skip to content. Breadcrumb Home About us News and views Three exciting diabetes tech developments horizon.

Save for later Page saved! You can go back to this later in your Diabetes and Me Close. Three exciting diabetes tech developments on the horizon. Further advances in closed loop As mentioned above, closed loop systems — sometimes called automated insulin delivery — are already changing diabetes care.

Continuous ketone monitoring CGM devices are familiar to many people living with diabetes, and similar thought is being given toward how to improve testing for other important measures like ketones. Non-invasive glucose monitoring Non-invasive glucose monitoring promises blood testing without the need for even the small needle that CGM sensors use to measure glucose levels.