Exercise in people with type 1 diabetes is associated with increased hypoglycaemia frequency and fear of hypoglycaemia. A potential role for regular anaerobic exercise (AnaE) to minimise hypoglycaemia has not been reported and was explored in this analysis.
Methods: n=79 adults with type 1 diabetes, 53% male, with mean±SD age 41.7±13.4 years, diabetes duration 18.3±13.2 years, HbA1c 8.3±1.4%, completed validated self-report questionnaires, pertaining to exercise type and frequency (Stanford), attitudes to exercise and fear of hypoglycaemia (HFS-II, FH-15). Only 6/79 that performed no exercise were excluded.
Results: On average, 209±193 minutes of weekly exercise was reported, with 192±164 minutes of AerE and 17.3 ± 47.8 minutes of AnaE, respectively. Only n=15 undertook AnaE, which all cases were combined with AerE, and total exercise averaged 1.9 fold more than AerE alone (n=58), with at least 83.0 minutes/week. While increased duration of total and AerE each correlated positively with fear of overall (r=0.30, P=0.01 and r=0.31, P=0.01) and nocturnal hypoglycaemia (r=0.30, P=0.01 and r=0.31, P=0.01), no such correlations were found for AnaE. Compared with undertaking similar duration AerE alone, AnaE was associated with ~3 fold fewer hypoglycaemia events (severe: 5.75vs1.90 /12 months P=0.041; mod.: 4.62vs1.55 /6months P=0.055; mild:4.02vs 1.35/month P=0.13, for AnaE vs AerE respectively).
For lack of hypoglycaemia awareness (LOHA), 52% sensed hypoglycaemia normally with BGL symptom threshold 3.3-3.8 mM, but 31% (2.7-3.2), 6% (2.7-2.2) and 10% (<2.2) mM. Data indicate that greater severity of LOHA occurs with greater duration of total or AerE, whereas increased AnaE relatively protects against more severe LOHA.
Conclusion: This self-reported data suggests that compared with aerobic exercise alone, anaerobic exercise in a mixed regimen may protect against hypoglycaemia and lack of hypoglycaemia awareness. A prospective intervention study of mixed exercise appears warranted to determine if it can help prevent exercise-induced hypoglycaemia in type 1 diabetes.