The Resistance Exercise in Already Active Diabetic Individuals (READI) Randomised Clinical Trial.

OBJECTIVE
To evaluate the incremental impact of resistance training on HbA1c, fitness, body composition and cardiometabolic risk factors in aerobically-active people with type 1 diabetes.


RESEARCH DESIGN AND METHODS
The Resistance Exercise in Already-active Diabetic Individuals (READI) trial (NCT00410436) was a four-centre randomized parallel-group trial. After a 5-week run-in period with diabetes management optimization, 131 aerobically-active individuals with type 1 diabetes were randomized to resistance exercise (n = 71, intervention - INT) or control (n = 60, CON) for 22 additional weeks. Both groups maintained their aerobic activities and were provided dietary counselling throughout. Exercise training was three times per week at community-based facilities. The primary outcome was HbA1c, and secondary outcomes included fitness (peak oxygen consumption, muscle strength), body composition (anthropometrics, dual-energy X-ray absorptiometry, computed tomography) and cardiometabolic risk markers (lipids, apolipoproteins). Assessors were blinded to group allocation.


RESULTS
There were no significant differences in HbA1c change between INT and CON. Declines in HbA1c [INT: 7.75 ± 0.10% (61.2 ± 1.1 mmol/mol) to 7.55 ± 0.10% (59 ± 1.1 mmol/mol); CON: 7.70 ± 0.11% (60.7 ± 1.2 mmol/mol) to 7.57 ± 0.11% (59.6 ± 1.3 mmol/mol); intergroup difference in change -0.07 [95% CI -0.31, 0.18]. Waist circumference decreased more in INT than CON after six months (p = 0.02). Muscular strength increased more in INT than in CON (p < 0.001). There were no intergroup differences in hypoglycemia or any other variables.


CONCLUSIONS
Adding resistance training did not impact glycemia, but it increased strength and reduced waist circumference, in aerobically active individuals with type 1 diabetes.