Classification of Physical Activity: Information to Artificial Pancreas Control Systems in Real Time

J Diabetes Sci Technol. 2015 Oct 6;9(6):1200-7. doi: 10.1177/1932296815609369.


Physical activity has a wide range of effects on glucose concentrations in type 1 diabetes (T1D) depending on the type (ie, aerobic, anaerobic, mixed) and duration of activity performed. This variability in glucose responses to physical activity makes the development of artificial pancreas (AP) systems challenging. Automatic detection of exercise type and intensity, and its classification as aerobic or anaerobic would provide valuable information to AP control algorithms. This can be achieved by using a multivariable AP approach where biometric variables are measured and reported to the AP at high frequency. We developed a classification system that identifies, in real time, the exercise intensity and its reliance on aerobic or anaerobic metabolism and tested this approach using clinical data collected from 5 persons with T1D and 3 individuals without T1D in a controlled laboratory setting using a variety of common types of physical activity. The classifier had an average sensitivity of 98.7% for physiological data collected over a range of exercise modalities and intensities in these subjects. The classifier will be added as a new module to the integrated multivariable adaptive AP system to enable the detection of aerobic and anaerobic exercise for enhancing the accuracy of insulin infusion strategies during and after exercise.

Keywords: aerobic and anaerobic exercise; multivariable artificial pancreas; real-time exercise classification.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Algorithms*
  • Biomarkers / blood
  • Blood Glucose / drug effects*
  • Blood Glucose / metabolism
  • Case-Control Studies
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / diagnosis
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Diabetes Mellitus, Type 1 / physiopathology
  • Energy Metabolism / drug effects
  • Equipment Design
  • Exercise Test
  • Exercise*
  • Female
  • Humans
  • Hypoglycemic Agents / administration & dosage*
  • Insulin / administration & dosage*
  • Insulin Infusion Systems*
  • Male
  • Middle Aged
  • Motor Activity*
  • Multivariate Analysis
  • Pancreas, Artificial*
  • Predictive Value of Tests
  • Reproducibility of Results
  • Signal Processing, Computer-Assisted
  • Time Factors
  • Treatment Outcome
  • Young Adult


  • Biomarkers
  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin