The goal of this study is to assess the impact of physician-driven insulin setting changes in type 1 patients using multiple daily injection insulin therapy with exercise. This is a short outpatient study with multiple outpatient and home exercise sessions with an assigned type of exercise.

Subjects will be on study for 28 days. Sensor glucose, exercise, insulin and meal data will be collected during this time. Subjects will wear the Dexcom G6 CGM system and a physical activity monitor. The Subjects will complete 2 exercise visits in-clinic and 4 exercise visits as an outpatient. Subjects will be randomized to aerobic, anaerobic or high intensity interval exercise sessions for 30 minutes each. Physicians will review CGM and insulin data every 7 days and make insulin dose recommendations that the subject will adjust in the dose calculator.

Inclusion Criteria:

• Diagnosis of type 1 diabetes mellitus for at least 1 year.
• Male or female subjects 18 to 50 years of age.
• Physically willing and able to perform 30 min of exercise (as determined by the investigator after reviewing the subject's activity level).
• Use of multiple daily insulin injections (MDI).
• A1C ≥7.0% at the time of screening.
• Current use of a smart phone.
• Willingness to follow all study procedures, including attending all clinic visits.
• Willingness to sign informed consent and HIPAA documents.

Exclusion Criteria:

• Female of childbearing potential who is pregnant or intending to become pregnant or breast-feeding, or is not using adequate contraceptive methods. Acceptable contraception includes birth control pill / patch / vaginal ring, Depo-Provera, Norplant, an IUD, the double barrier method (the woman uses a diaphragm and spermicide and the man uses a condom), or abstinence.
• Any cardiovascular disease, defined as a clinically significant EKG abnormality at the time of screening or any history of: stroke, heart failure, myocardial infarction, angina pectoris, or coronary arterial bypass graft or angioplasty. Diagnosis of 2nd or 3rd degree heart block or any non-physiological arrhythmia judged by the investigator to be exclusionary.
• Renal insufficiency (GFR < 60 ml/min, using the MDRD equation as reported by the OHSU laboratory).
• Liver failure, cirrhosis, or any other liver disease that compromises liver function as determined by the investigator.
• Hematocrit of less than 36% for men, less than 32% for women.
• History of severe hypoglycemia during the past 12 months prior to screening visit or hypoglycemia unawareness as judged by the investigator. Subjects will complete a hypoglycemia awareness questionnaire. Subjects will be excluded for four or more R responses.
• Adrenal insufficiency.
• Any active infection.
• Known or suspected abuse of alcohol, narcotics, or illicit drugs.
• Seizure disorder.
• Active foot ulceration.
• Peripheral arterial disease.
• Major surgical operation within 30 days prior to screening.
• Use of an investigational drug within 30 days prior to screening.
• Chronic usage of any immunosuppressive medication (such as cyclosporine, azathioprine, sirolimus, or tacrolimus).
• Bleeding disorder or platelet count below 50,000.
• Allergy to aspart or glargine insulin.
• Need for uninterrupted treatment of acetaminophen.
• Current administration of oral or parenteral corticosteroids.
• Any life threatening disease, including malignant neoplasms and medical history of malignant neoplasms within the past 5 years prior to screening (except basal and squamous cell skin cancer).
• Beta blockers or non-dihydropyridine calcium channel blockers.
• Current use of any medication intended to lower glucose other than insulin (ex. use of liraglutide).
• A positive response to any of the questions from the Physical Activity Readiness Questionnaire with one exception: subject will not be excluded if he/she takes a single blood pressure medication that doesn't impact heart rate and blood pressure is controlled on the medication (blood pressure is less than 140/90 mmHg).
• Any chest discomfort with physical activity, including pain or pressure, or other types of discomfort.
• Any clinically significant disease or disorder which in the opinion of the Investigator may jeopardize the subject's safety or compliance with the protocol.

28 days

All participants that started a visit are included in the adverse events. All subjects completed all visits except one. That subject only completed the start up visit.