Lowering Impaired Fasting Glucose Levels With Exercise

  • End date
    Sep 27, 2021
  • participants needed
  • sponsor
    University of Missouri-Columbia
Updated on 27 January 2021


Morning hyperglycemia plays a role in the future development of insulin resistance and type 2 diabetes (T2D) (8) and is associated with numerous microvascular and cardiovascular complications and renal disease. These augmented morning glucose levels are due to an elevated endogenous glucose production (EGP), as a result of a loss of coordination between glucose levels and insulin secretion, and possibly hyperglucagonemia during the overnight period. Exercise stimulates glucose uptake and increases insulin sensitivity acutely, and may be the best lifestyle intervention to minimize the nocturnal rise in glucose levels. Prescription of the timing of exercise relative to a meal and/or to the overnight period may be particularly critical for individuals that have impaired fasting glucose (IFG) levels. Surprisingly little is known about the overnight period when elevated EGP and the synchrony between glucose and c-peptide/glucagon levels becomes disturbed. This novel study will provide insight into the hormonal/metabolic milieu of a dinner meal, the evening and overnight period that occurs in non-obese, OB and OB+IFG individuals; it will also establish if the timing of exercise can attenuate nocturnal glucose elevations, and if this is associated with improved hormonal synchrony. This project will compare EGP, -cell function and hormonal responses between morning and evening exercise on the postprandial and overnight period in obese individuals with/without IFG levels. Fifty-four subjects will be studied during the evening meal (EGP and -cell function), postprandially and through the overnight period (1600-0700 h), allowing us to examine some of the potential mechanisms for the elevation in overnight glucose levels. This is the first study that will examine this issue from pre-dinner through the night while previous studies have only examined chronically fasted individuals and this study will lay the groundwork for understanding the pathology of the predawn phenomena in OB+IFG individuals. These potentially translational findings may impact the efficiency of physician communication to patients concerning exercise. These investigators are one of the few groups that study subjects through the overnight period and have the facilities and capability to do this research.


In individuals with type 2 diabetes (T2D), chronically elevated glucose and insulin levels result in numerous health complications. Maintaining tight glucose control is difficult for individuals with T2D, particularly in the postprandial period and in the morning period just prior to waking. In the postprandial period, the combined effect of insulin resistance and beta cell dysfunction results in a prolonged elevation in glucose levels, and augmented insulin levels in an attempt to reduce the circulating glucose levels. In the overnight period, there is evidence of enhanced endogenous glucose production and of a disruption of the interaction between glucose levels and insulin secretion. Early work in individuals with T2D demonstrated that with continued fasting, glucose levels stopped declining in the evening and subsequently rose throughout the night to reach a morning maximum, and this elevation persisted till noon. Additionally these authors demonstrated that insulin levels and insulin secretion rates did not parallel the nocturnal glucose changes in individuals with T2D, while in the controls the nocturnal glucose and insulin secretion rates coincided. Evidence is also emerging that hyperglucagonemia may be occurring in the setting of deficient insulin secretion, and may be playing a role in the elevated postprandial glucose levels and in the overnight period. These studies provide preliminary evidence that there is disruption in the fine coordination between glucose levels and glucagon and insulin secretion, and that this is exacerbated more in the overnight period than during the waking hours. Previous studies examining the overnight period have been conducted following prolonged fasting (~24-34 h), however, most people do not fast for extended periods of time prior to going to bed. Additionally, individuals with T2D often know that meal composition the evening prior can exacerbate the elevated fasting glucose levels the following morning, thus highlighting the need to examine the effect of meal composition on overnight glucose control. To date, very little is known about the pathology of why fasting glucose levels are elevated in many obese individuals. There appears to be asynchrony between glucose and insulin levels in the overnight period but very little research has focused on this phenomenon or how meal composition affects overnight glucose levels. This study will provide evidence of potential mechanisms for the elevation in overnight glucose levels and the findings will be translatable for individuals with impaired fasting glucose (IFG) levels to understand the importance of meal composition in the evening period.

The specific aims of this project are:

  1. To examine the hormonal responses (glucagon, c-peptide, insulin, incretins) in response to a meal in the postprandial period and the synchronization between glucose and insulin/glucagon during the overnight period in non-obese individuals and obese individuals with impaired fasting glucose levels (IFG).
  2. To determine if the meal composition (standard meal: 55% carbohydrate, 20% protein, 25% fat vs. high fat/fructose: 40% carbohydrate- 25% fructose, 40% fat, 20% protein) will alter the hormonal responses (glucagon, insulin, incretin) in the postprandial period, and if this change in meal composition will impact glucagon levels and glucose/c-peptide synchrony in the overnight period.

Experimental design: Subjects will participate three times; 1) no exercise, 2) 2 hr post dinner exercise, and 3) morning exercise (~7am). The order in which subjects undergo each treatment will be randomized prior to study enrollment. Eligible subjects will initially undergo baseline testing for assessment of body composition, exercise stress test and blood screening. All subjects will have impaired fasting glucose levels. All subjects will undergo 3 study days that will start at ~1600 h and continue until 0700 h the following morning. They will receive a standard meal (55% carbohydrate, 20% protein, 25% fat) at 1800 h and blood samples will be taken from ~4:30 pm until 7 am.

Condition Type2 Diabetes
Treatment No Exercise, Morning exercise, Evening exercise
Clinical Study IdentifierNCT03019510
SponsorUniversity of Missouri-Columbia
Last Modified on27 January 2021


Yes No Not Sure

Inclusion Criteria

Is your age between 25 yrs and 65 yrs?
Gender: Male or Female
Do you have Type2 Diabetes?
Do you have any of these conditions: Do you have Type2 Diabetes??
-65 yrs of age body mass index (BMI): 30-45 kg/m2 for the obese subjects
<24.5 kg/m2 for the non-obese subjects weight stable during prior 6 months
non-smokers OB with impaired fasting glucose: elevated elevated morning
fasting glucose levels >110 mg/dL for 5 of 7 days non-obese and OB subjects
fasting glucose levels < 100 mg/dL - 2hr OGTT glucose value <140 mg/dL
Exclusion criteria overt cardiovascular disease sleep apnea surgical history
for weight loss use of weight-loss medications or active dieting participate
in exercise > 3 days/wk per week at a moderate or vigorous intensity pregnant
or lactating women. Medications for glycemic control (including insulin)
blockers, glucocorticoids, testosterone, or other medications for chronic
pulmonary, cardiac or other systemic diseases
Significant hypertension BP > 180 systolic or > 100 diastolic, at rest
Untreated hypothyroidism or hyperthyroidism (will be included if treated and
euthyroid) Active users of tobacco and chronic alcohol abuse. Renal, hepatic
pulmonary, adrenal, or pituitary disease. Liver function tests with > 2xULN
Clear my responses

How to participate?

Step 1 Connect with a site
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact


Phone Email

Please verify that you are not a bot.

Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note