Effects of Long Duration Cycling in People With Type 1 Diabetes (PEDAL-T1D)

Universitat de Girona

Status: Active, not recruiting

Conditions: Type 1 Diabetes (T1D)

Treatments: Behavioral: Prolonged moderate-intensity cycling session

Study type: Interventional

Funder types: Other; NETWORK

Identifiers

NCT07286019

2025.110 (Other Identifier)

UdG-PEDAL-T1D

Details and patient eligibility

About

The goal of this interventional study is to build a high quality, real world multimodal dataset that combines continuous glucose monitoring (CGM), wearable and fitness data, performance metrics, and saliva and urine omics collected during a prolonged, moderate intensity outdoor gravel-cycling session in adults with type 1 diabetes (T1D).

The main questions it aims to answer are:

• Can we collect and synchronize comprehensive CGM, physiological, performance, and omics data around a single cycling session to enable further artificial intelligence (AI) model development?
• What molecular changes in saliva and urine occur during exercise, and how do they relate to glycemic outcomes?

Participants will:

• Complete a supervised ~75 km gravel-cycling route at their own pace under real-world conditions, without protocolized therapy adjustments.
• Wear a Dexcom G7 starting ~4 days before the ride and continue through the sensor lifespan to capture CGM data.
• Provide saliva and urine immediately before and after the ride for epigenomic and proteomic analyses.

This study will generate an integrated resource that supports the development and validation of AI models for predicting glucose responses to exercise in T1D and will help guide future studies on how prolonged exercise affects glucose control.

Enrollment: 29 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Type 1 diabetes for > 5 years.
• Age between 18-60 years.
• HbA1c ≤ 8.5%.
• Body mass index between 18 and 30 kg/m².
• Physically active (≥ 4 hours/week of exercise).
• Laboratory data and EKG without alterations of the last 12 months.
• Valid Type 2 sports medical examination, which includes a monitored stress test with continuous ECG and blood pressure monitoring, as well as an official medical certificate confirming fitness to participate in this study.
• Experience using CGM sensors and be used to self-monitor blood glucose and carbohydrate counting.

Exclusion criteria

• Unable to ride gravel bikes.
• Unable to use clipless pedals.
• Pregnancy and breastfeeding.
• Hypoglycemia unawareness (Clarke Test > 3).
• Severe hypoglycemia in the previous 6 monhts.
• Progressive fatal disease.
• History of drug or alcohol abuse.
• Impaired liver function.
• Clinically relevant microvascular complications (macroalbuminuria, pre-proliferative and proliferative retinopathy), cardiovascular, hepatic, neurological, endocrine or other systemic disease, apart from T1D.
• Mental conditions that prevent the subject from understanding the nature, purpose and possible consequences of the study.
• Using an experimental drug or device during the prior 30 days.

Inclusion (healthy control group): adults 18-60 years without diabetes and physically active (≥ 4 hours/week of exercise) who can provide pre/post saliva and uringe samples for omics analyses.

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

29 participants in 2 patient groups

Adults with type 1 diabetes

Experimental group

Description:

Adults with type 1 diabetes complete one supervised outdoor gravel cycling route of \~75 km under real-world conditions that represent moderate-intensity cycling. Intensity is not prescribed by the protocol and participants will regulate their effort themselves. Participants continue their usual insulin therapy with no protocolized insulin adjustments. A Dexcom G7 sensor is started \~4 days before the event and worn through its life to capture baseline/during/post-exercise data. Saliva and urine are collected immediately before and after the ride for omics analyses.

Treatment:

Behavioral: Prolonged moderate-intensity cycling session

Adults without diabetes

Experimental group

Description:

Adults without diabetes complete the same supervised gravel cycling route of \~75 km under real-world, moderate intensity conditions. Intensity is not prescribed by the protocol and participants will regulate their effort themselves. A Dexcom G7 sensor is started \~4 days before the event and worn through its life to capture glycemic data. Saliva and urine are collected immediately before and after the ride for omics analyses.

Treatment:

Behavioral: Prolonged moderate-intensity cycling session