Prolonged physical exercise (PE) is a challenge in type 1 diabetes with an increased incidence of both hypoglycemia and hyperglycemia.

The purpose was to evaluate the impact of two consecutive days of carbohydrate (CHO) loading, followed by high intermittent CHO-intake during prolonged PE, facilitated by a proactive use of Real-Time Continuous Glucose Monitoring (rtCGM), on glucose control in individuals with type 1 diabetes.

Ten physically active individuals with type 1 diabetes were invited to participate in a 3-day long sports camp with the objective to evaluate CHO-loading and high intermittent CHO-intake during prolonged PE. 1.5 months later the same procedure was evaluated during a 90 km cross-country skiing race. Participants were instructed to act proactively using rtCGM with predictive alerts set for high and low glucose values to maintain sensor glucose values within target range, defined as 72-180 mg/dl (4-10 mmol/l).

This is a descriptive, single arm, non-randomized interventional study. The intervention consisted of carbohydrate loading prior to and intermittent high carbohydrate intake during physical exercise and a proactive use of Real-Time Continuous Glucose Monitoring (rtCGM) to achieve and maintain glucose control.

Central Contact Person Stig A Mattsson, dietician PhD student Phone: +46702047759 E-mail: stigmattsson@live.com

IPD Sharing Statement No: There is not a plan to make IPD available.

Inclusion criteria:

• age 18-50 years
• type 1 diabetes
• diabetes duration >1 year
• exercising regularly ≥3 workout/week
• previous experience from cross-country skiing

Exclusion Criteria:

• A1c 8.6% NGSP (70 mmol/mol IFCC)
• proliferative retinopathy
• known nephropathy
• cardiac failure
• following a low-carbohydrate diet.

We will not share participants' data with other researchers.