Clinical Trial: Fat and Sugar Metabolism During Exercise in Patients With Metabolic Myopathy

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

Official Title: Fat and Sugar Metabolism During Exercise in Patients With Metabolic Myopathy

Brief Summary: This study aims to characterize the pathophysiological mechanisms of 21 different metabolic myopathies. The study will focus on exercise capacity and the metabolic derangement during exercise.

Detailed Summary:

Patients will be compared to a group of matched healthy control subjects (matched for age, gender, physical activity level and BMI) for comparison of the primary and secondary outcome measures.

Methods:

Each subject will go through 3 test days.

Test day 1:

• International Physical Activity Questionnaire (IPAQ). The results will be used to match the patients to control subjects.
• DEXA-scan. This is used to estimate the volume of distribution for stable isotope tracers.
• Maximal oxidative capacity test (max-test). On a cycle ergometer, subjects will exercise for approximately 15 minutes with increasing resistance until exhaustion. The peak oxidative and workload capacities will be compared to the healthy controls and will be used to find the workload that corresponds to 55-65 % of VO2max used in the following exercise tests.
• Blood samples. Samples will be drawn before exercise and at exhaustion and will be analyzed for the plasma concentrations of glucose, lactate, ammonia, creatine kinase and myoglobin.

Test day 2:

•Long exercise test #1. The purpose of this test is to measure the total fat and sugar oxidation rates during exercise by using stable isotope tracers.

Subjects arrive at the laboratory after 3-9 hours of fasting. One IV-catheter is inserted in the cubital vein in one arm and another in a peripheral vein in the other hand. The stable isotope tracers will be given in the cubital vein as a constant infusion of solutions of: Sponsor: Rigshospitalet, Denmark

Current Primary Outcome: Total fat oxidation (rate of disappearance) during prolonged moderate intensity exercise. Measured as micro mol per kg per minute. [ Time Frame: Measured at at time (minutes) -120, -20, -10, 0, 10, 20, 30, 40, 50, 60. Zero is the indicatet start of 1 hour cycling test. Measured on day 2 of participation ]

Original Primary Outcome:

• Total fat oxidation (rate of disappearance) during prolonged moderate intensity exercise. Measured as micro mol per kg per minute. [ Time Frame: Measured at at time (minutes) -120, -20, -10, 0, 10, 20, 30, 40, 50, 60. Zero is the indicatet start of 1 hour cycling test. Measured on day 2 of participation ]
  Measured using stable isotope technique ([U-13C]-palmitate, [1,1,2,3,3-2H5]-glycerol and [6.6-2H2]-glucose ) and indirect calorimetry.
• Total glucose oxidation (rate of disappearance) during prolonged moderate intensity exercise. Measured as micro mol per kg per minute. [ Time Frame: Measured at at time (minutes) -120, -20, -10, 0, 10, 20, 30, 40, 50, 60. Zero is the indicatet start of 1 hour cycling test. Measured on day 2 of participation ]
  Measured using stable isotope technique ([U-13C]-palmitate, [1,1,2,3,3-2H5]-glycerol and [6.6-2H2]-glucose ) and indirect calorimetry.

Current Secondary Outcome:

• Maximal oxidative capacity (mL*kg-1*minutes-1) [ Time Frame: Day 1 of participation ]
  Oxidative capacity is measured continuously during a maximum exercise test on the first day of the trial. The test lasts about 15 minutes (when the participant is fully exhausted). The maximal oxidative capacity is the peak measure during the test.
• Endurance measured as minutes:seconds [ Time Frame: Day 2 and 4 of participation ]
  During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. The test will last for 1 hour or until exhaustion. Endurance will be defined as the total exercise duration.
• Heart rate (HR) during prolonged exercise, with and without blood sugar maintained by an infusion of a 10% glucose solution. Measured in beats per minute. [ Time Frame: During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. ]
  During 1 hour cycling at 55-65% of VO2max the heart rate is measured every 2 minuts.
• Oxygen consumption rate (VO2) during prolonged exercise, with and without blood sugar maintained by an infusion of a 10% glucose solution. Measured in mL. [ Time Frame: During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. ]
  During 1 hour cycling at 55-65% of VO2max the oxygen consumption rate is continuously measured.
• Self-evaluated exertion (Rate of Perceived Exertion (RPE)) during prolonged exercise, with and without blood sugar maintained by an infusion of a 10% glucose solution. Measured using a Borg-scale (6-20). [ Time Frame: During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. ]
  During 1 hour cycling at 55-65% of VO2max the participant is asked to rate their exertion every 2 minutes.
• Maximal workload capacity. Measured in watt [ Time Frame: Day 1 of participation ]
  The participant will be cycling at incremental workload until exhaustion. The test lasts about 15 minutes (when the participant is fully exhausted). The maximal workload is the peak measure at the end of the test.
• Total glucose oxidation (rate of disappearance) during prolonged moderate intensity exercise. Measured as micro mol per kg per minute. [ Time Frame: Measured at at time (minutes) -120, -20, -10, 0, 10, 20, 30, 40, 50, 60. Zero is the indicatet start of 1 hour cycling test. Measured on day 2 of participation ]
  Measured using stable isotope technique ([U-13C]-palmitate, [1,1,2,3,3-2H5]-glycerol and [6.6-2H2]-glucose ) and indirect calorimetry.

Original Secondary Outcome:

• Maximal oxidative capacity (mL*kg-1*minutes-1) [ Time Frame: Day 1 of participation ]
  Oxidative capacity is measured continuously during a maximum exercise test on the first day of the trial. The test lasts about 15 minutes (when the participant is fully exhausted). The maximal oxidative capacity is the peak measure during the test.
• Endurance measured as minutes:seconds [ Time Frame: Day 2 and 4 of participation ]
  During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. The test will last for 1 hour or until exhaustion. Endurance will be defined as the total exercise duration.
• Heart rate (HR) during prolonged exercise, with and without blood sugar maintained by an infusion of a 10% glucose solution. Measured in beats per minute. [ Time Frame: During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. ]
  During 1 hour cycling at 55-65% of VO2max the heart rate is measured every 2 minuts.
• Oxygen consumption rate (VO2) during prolonged exercise, with and without blood sugar maintained by an infusion of a 10% glucose solution. Measured in mL. [ Time Frame: During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. ]
  During 1 hour cycling at 55-65% of VO2max the oxygen consumption rate is continuously measured.
• Self-evaluated exertion (Rate of Perceived Exertion (RPE)) during prolonged exercise, with and without blood sugar maintained by an infusion of a 10% glucose solution. Measured using a Borg-scale (6-20). [ Time Frame: During 1 hour cycling test 1 and 1 hour cycling test 2 on day 2 and 4 of participation. ]
  During 1 hour cycling at 55-65% of VO2max the participant is asked to rate their exertion every 2 minutes.
• Maximal workload capacity. Measured in watt [ Time Frame: Day 1 of participation ]
  The participant will be cycling at incremental workload until exhaustion. The test lasts about 15 minutes (when the participant is fully exhausted). The maximal workload is the peak measure at the end of the test.

Information By: Rigshospitalet, Denmark

Dates:
Date Received: December 9, 2015
Date Started: January 2016
Date Completion: December 2020
Last Updated: April 5, 2016
Last Verified: April 2016