The goal of this pilot study is to evaluate the magnitude of changes in glucose and hormone levels in response to structured exercise in the fasting state in individuals with post-bariatric hypoglycemia (PBH).

This pilot study will assess the adequacy of a protocol to test the following hypotheses: (1) hypoglycemia will develop in individuals with PBH in response to exercise; (2) counterregulatory hormonal responses to hypoglycemia during exercise are impaired in individuals with PBH.

Inclusion Criteria:

1. Males or females diagnosed with ongoing post-bariatric hypoglycemia with prior episodes of neuroglycopenia, unresponsive to dietary intervention (low glycemic index, controlled carbohydrate portions) and trial of acarbose therapy at the maximally tolerated dose.
2. Age 18-60 years of age, inclusive, at screening.
3. Willingness to provide informed consent and follow all study procedures, including attending all scheduled visits.

Exclusion Criteria:

Initial general screening will be performed during an initial phone or in person visit (e.g. during a clinical visit). Individuals who appear to meet criteria will be invited for a screening visit, when a detailed history and physical exam will be performed by study clinicians. Inclusion and exclusion criteria will be reviewed after the visit to determine study eligibility.

Inclusion criteria:

1. Males or females diagnosed with ongoing post-bariatric hypoglycemia with prior episodes of neuroglycopenia, unresponsive to dietary intervention (low glycemic index, controlled carbohydrate portions) and trial of acarbose therapy at the maximally tolerated dose.
2. Age 18-60 years of age, inclusive, at screening.
3. Willingness to provide informed consent and follow all study procedures, including attending all scheduled visits.

Exclusion criteria:

1. Inability to exercise or medical contraindication to exercise;
2. Documented hypoglycemia occurring in the fasting state (> 12 hours fast);
3. Chronic kidney disease stage 4 or 5 (including end-stage renal disease);
4. Hepatic disease, including serum alanine transaminase (ALT) or aspartate transferase (AST) greater than or equal to 3 times the upper limit of normal; hepatic synthetic insufficiency as defined as serum albumin < 3.0 g/dL; or serum bilirubin > 2.0;
5. Congestive heart failure, New York Heart Association (NYHA) class II, III or IV;
6. History of myocardial infarction, unstable angina or revascularization within the past 6 months or 2 or more risk factors for coronary artery disease including diabetes, uncontrolled hypertension, uncontrolled hyperlipidemia, and active tobacco use;
7. History of syncope (unrelated to hypoglycemia) or diagnosed cardiac arrhythmia;
8. Concurrent administration of β-blocker therapy;
9. History of a cerebrovascular accident;
10. Seizure disorder (other than with suspect or documented hypoglycemia);
11. Active treatment with any diabetes medications except for acarbose and miglitol;
12. Active treatment with a somatostatin analogue (both long and short acting) or diazoxide;
13. Active malignancy, except basal cell or squamous cell skin cancers;
14. Personal or family history of pheochromocytoma or disorder with increased risk of pheochromocytoma(MEN 2, neurofibromatosis, or Von Hippel-Lindau disease);
15. Known insulinoma;
16. Major surgical operation within 30 days prior to screening;
17. Hematocrit < 33% (women) or <36% (men);
18. Bleeding disorder, treatment with warfarin, or platelet count <50,000;
19. Blood donation (1 pint of whole blood) within the past 2 months;
20. Active alcohol abuse or substance abuse;
21. Current administration of oral or parenteral corticosteroids;
22. Pregnancy and/ or Lactation: For women of childbearing potential: there is a requirement for a negative urine pregnancy test and for agreement to use contraception during the study and for at least 1 month after participating in the study. Acceptable contraception includes birth control pill / patch / vaginal ring, Depo-Provera, Norplant, an intra-uterine device (IUD), the double barrier method (the woman uses a diaphragm and spermicide and the man uses a condom), or abstinence;
23. Use of an investigational drug within 30 days prior to screening.

There will be no involvement of special vulnerable populations such as fetuses, neonates, pregnant women, children, prisoners, institutionalized or incarcerated individuals, or others who may be considered vulnerable populations.