Fitness and physical activity in youth with type 1 diabetes mellitus in good or poor glycemic control.
BACKGROUND
Patients with type 1 diabetes mellitus (T1DM) may experience poor muscle health as a result of chronic hyperglycemia. Despite this, muscle function in children with T1DM with good or poor glycemic control has yet to be examined in detail.


OBJECTIVE
To assess differences in muscle-related fitness variables in children with T1DM with good glycemic control (T1DM-G), as well as those with poor glycemic control (T1DM-P), and non-diabetic, healthy controls.


METHODS
Eight children with T1DM-G [glycosylated hemoglobin (HbA1c) ≤ 7.5% for 9 months], eight children with T1DM-P (HbA1c ≥ 9.0% for 9 months), and eight healthy controls completed one exercise session.


METHODS
Anaerobic and aerobic muscle functions were assessed with a maximal isometric grip strength test, a Wingate test, and an incremental continuous cycling test until exhaustion. Blood samples were collected at rest to determine HbA1c at the time of testing. Physical activity was monitored over 7 d using accelerometry.


RESULTS
Children with T1DM-P displayed lower peak oxygen consumption (VO2peak ) values (mL/kg/min) compared to healthy controls (T1DM-P: 33.2 ± 5.6, controls: 43.5 ± 6.3, p < 0.01), while T1DM-G (43.5 ± 6.3) had values similar to controls and T1DM-P. There was a negative relationship between VO2peak and HbA1c% (r = -0.54, p < 0.01). All groups were similar in all other fitness variables. There were no group differences in physical activity variables.


CONCLUSIONS
Children with T1DM-G did not display signs of impaired muscle function, while children with T1DM-P have signs of altered aerobic muscle capacity.
Child Health and Exercise Medicine Program, Department of Pediatrics, McMaster University, Hamilton, ON, L8S 4L8, Canada.
Thanh
T
Nguyen
Joyce
J
Obeid
Rachel G
RG
Walker
Matthew P
MP
Krause
Thomas J
TJ
Hawke
Karen
K
McAssey
John
J
Vandermeulen
Brian W
BW
Timmons
D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism*; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D015444:Exercise / Q000502:physiology; D005260:Female; D018737:Hand Strength; D006339:Heart Rate; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D053580:Muscle Strength; D010101:Oxygen Consumption; D010809:Physical Fitness / Q000502:physiology*; D011659:Pulmonary Gas Exchange / Q000502:physiology
D001786:Blood Glucose
fitness; glycemic control; muscle function; type 1 diabetes mellitus