title: Effects of acute caffeine supplementation on reducing exercise-associated hypoglycaemia in individuals with Type 1 diabetes mellitus.
abstract: OBJECTIVE
  To determine the effects of acute caffeine ingestion on glycaemia during moderate to vigorous intensity aerobic exercise and in recovery in individuals with Type 1 diabetes.
  
  
  METHODS
  A total of 13 patients with Type 1 diabetes [eight women, five men: mean ± sd age 25.9 ± 8.8 years, BMI 71.9 ± 11.0 kg, maximal oxygen consumption 46.6 ± 12.7 ml/kg/min, body fat 19.9 ± 7.2%, duration of diabetes 14.4 ± 10.1 years and HbA1c 55 ± 8 mmol/mol (7.4 ± 0.8%)] were recruited. Participants ingested capsules that contained gelatin or pure caffeine (6.0 mg/kg body mass) and performed afternoon exercise for 45 min at 60% maximal oxygen consumption on two separate visits with only circulating basal insulin levels.
  
  
  RESULTS
  The main finding was that a single caffeine dose attenuates the drop in glycaemia by 1.8 ± 2.8 mmol/l compared with placebo intake during exercise (P=0.056). Continuous glucose monitoring data, however, showed that caffeine was associated with elevated glycaemia at bedtime after exercise, compared with placebo, but lower glucose concentrations in the early morning the next day.
  
  
  CONCLUSIONS
  Caffeine intake should be considered as another strategy that may modestly attenuate hypoglycaemia in individuals with Type 1 diabetes during exercise, but should be taken with precautionary measures as it may increase the risk of late-onset hypoglycaemia.
authors.affiliation: Department of Kinesiology and Health Science, Faculty of Health, Muscle Health Research Center and Physical Activity and Chronic Disease Unit, York University, Toronto, Ontario, Canada.
authors.forename: D P
authors.initials: DP
authors.lastname: Zaharieva
authors.affiliation: Department of Kinesiology and Health Science, Faculty of Health, Muscle Health Research Center and Physical Activity and Chronic Disease Unit, York University, Toronto, Ontario, Canada.
authors.forename: L A
authors.initials: LA
authors.lastname: Miadovnik
authors.affiliation: Department of Kinesiology and Health Science, Faculty of Health, Muscle Health Research Center and Physical Activity and Chronic Disease Unit, York University, Toronto, Ontario, Canada.
authors.forename: C P
authors.initials: CP
authors.lastname: Rowan
authors.affiliation: Department of Kinesiology and Health Science, Faculty of Health, Muscle Health Research Center and Physical Activity and Chronic Disease Unit, York University, Toronto, Ontario, Canada.
authors.forename: R J
authors.initials: RJ
authors.lastname: Gumieniak
authors.affiliation: Department of Kinesiology and Health Science, Faculty of Health, Muscle Health Research Center and Physical Activity and Chronic Disease Unit, York University, Toronto, Ontario, Canada.
authors.forename: V K
authors.initials: VK
authors.lastname: Jamnik
authors.affiliation: Department of Kinesiology and Health Science, Faculty of Health, Muscle Health Research Center and Physical Activity and Chronic Disease Unit, York University, Toronto, Ontario, Canada.
authors.forename: M C
authors.initials: MC
authors.lastname: Riddell
mesh_terms: D000293:Adolescent; D000328:Adult; D002110:Caffeine / Q000009:adverse effects / Q000627:therapeutic use*; D000697:Central Nervous System Stimulants / Q000009:adverse effects / Q000627:therapeutic use*; D002940:Circadian Rhythm; D003131:Combined Modality Therapy / Q000009:adverse effects; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000178:diet therapy* / Q000188:drug therapy / Q000628:therapy; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D015444:Exercise; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007003:Hypoglycemia / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000009:adverse effects / Q000627:therapeutic use; D007328:Insulin / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D018670:Monitoring, Ambulatory; D009864:Ontario / Q000453:epidemiology; D012306:Risk; D055815:Young Adult
chemical_list: D002110:Caffeine; D000697:Central Nervous System Stimulants; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; C517652:hemoglobin A1c protein, human