Glucose level recommendations have yet to be established for adolescents diagnosed with type 1 diabetes (T1D) who participate in VO2 max exercise testing for clinical or strength and conditioning purposes. Although a decrease in glucose may be expected throughout, and immediately after exercise testing, a minimal pre-test glucose setpoint has not been established to reduce the risk of hypoglycemia. Retrospective medical and sports medicine chart reviews were conducted of clinical pediatric sports medicine and physical activity program patients with a diagnosis of T1D (N = 24; mean age = 15.5 ± 1.7 years; male = 14, 58.3%) who participated in a modified Bruce protocol for maximal oxygen uptake (VO2 max). The majority of the participants identified as non-Hispanic (n = 22, 91.7%) and white (n = 19, 79.2%). Their average body mass index (BMI) based on age and sex was in the 66th percentile ± 19.5 and their average hemoglobin A1c (HbA1c) was 8.8% ± 1.8. Almost 2/3 of the participants (n = 15, 62.5%) wore a continuous glucose monitor. Their average VO2 max peak was 43.7 ml/kg/min ± 7.1. A paired-samples t-test was employed to detect a statistically significant reduction in glucose levels between pretest (< 30 minutes, mean = 191.1 mg/dl ± 61.2) and post-test VO2 max (< 5 minutes, mean = 166.7 mg/dl ± 57.9); t(21) = 2.3, p <. 05). The American Diabetes Association recommends that glucose levels do not fall below 70 mg/dl in order to prevent symptoms of hypoglycemia. These results demonstrated a mean decrease in glucose of 24.4 mg/dl and provide further data which can be used to set safety parameters and expectations for adolescents with T1D participating in VO2 max testing.


K. King: None. B. J. Thrasher: None. T. E. Mckay: None. K. A. Wintergerst: None.

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