Table 1 Inclusion and exclusion criteria

Participants older than 18 years

More than 2 years of established T1D

Stable insulin regimen in the past 6 months indexed by less than 20% change in total insulin daily dose

HbA1c less than 9.0%

Weekly physical activity of 90 min or more

Participation in recreational or competitive soccer-related activities, at least four times per month

Participants able to provide informed consent

Any treatment regimen different from continuous subcutaneous insulin infusion or multiple daily insulin injections

Any use of medications (other than insulin) known to affect glycemic control including oral or parenteral steroids (except for inhaled steroids), metformin, SGLT2 inhibitors, GLP.1 agonists, thiazolidinedione, sulfonylureas, DPP-4 inhibitors, or any other oral antidiabetic therapy

Detectable C-peptide in serum

Cognitive impairment comprising any substantial decrease in alertness, language reception, or attention that might interfere with understanding instructions for motor and cognitive testing, not including hypoglycemia unawareness

Chronic kidney disease (glomerular filtration rate less than 90 mL · min^-1)

Chronic liver failure (Child-Pugh B or C)

Advanced diabetic retinopathy

Pregnancy

Color blindness