An interventional study of Timing of exercise and Timing of exercise in Prediabetes and Overweight , Obesity, sponsored by German Diabetes Center. Recruiting at 1 site in Germany. Open to participants aged 19 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-09-11.
Sponsored by German Diabetes Center · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to find out whether exercising at the right time of day, based on a person's natural body clock, leads to greater health benefits in people living with prediabetes. The main question it aims to answer is whether doing a single session of exercise in the morning or in the evening affects how the body handles sugar differently in adults with prediabetes who have an extreme natural body clock. This will be done by comparing three conditions (no-exercise, morning exercise, and evening exercise) within the same participant. Each condition will be tested on a different day, with at least 14 days between the test days. During the no-exercise test days, participants will come to the study centre and will only be allowed to do sedentary activities (e.g. office work, reading, or screen time). During the morning exercise test days, participants will perform an exercise session at 9:00 am that involves short periods of very hard effort followed by short rest periods. Whereas for the evening exercise test days, the same type of exercise will be performed at 5:00 pm.
Chronotype refers to an individual's circadian preferences for being active and fully functional at certain times of the day. Using validated questionnaires, individual's chronotype can be categorized to either a morning (lark), evening (owl), or intermediate (neutral) chronotypes. Individuals with morning chronotype wake up and go to bed early. Therefore, their calorie distribution as well as peak mental and physical performances predominantly occur earlier in the day. This is in contrast with individuals with evening chronotype that wake up and go to bed late, resulting in most of their calorie consumption happens later in the day. They are also more active and alert in the evening. Growing evidence has shown that late afternoon or evening exercise is better than morning exercise for blood glucose control in individuals with type 2 diabetes (T2D) or those at risk of T2D. In men with T2D, two weeks of high-intensity interval training (HIIT) reduced continuous glucose monitor (CGM)-based glucose concentration when performed in the afternoon than in the morning. This finding was further supported by a retrospective study involving men at risk for or T2D that found afternoon exercise led to superior peripheral insulin sensitivity, insulin-mediated suppression of adipose tissue lipolysis, and fasting plasma glucose. Interestingly, in a recently published crossover trial involving men and women, with and without T2D, no difference was observed in 24-hour glucose profile assessed using CGM across all cohorts (including gender and diabetes status) between morning and evening exercise. However, morning exercise increased post-exercise blood glucose levels during the two hours recovery period in both men and women with T2D, which was not observed following the evening exercise. It is important to note that all the above-mentioned studies are either excluding individuals with extreme chronotype or the chronotype of the participants was not clearly reported. This limitation raises an important research question: Do people living with extreme chronotype respond differently to timed exercise? Therefore, in this study, it is hypothesize that people living with prediabetes and extreme chronotype will gain superior metabolic benefits when the timing of exercise is aligned with their chronotype. To test this, a randomized controlled cross-over study is conducted in which participants are subjected to three conditions that are no-exercise, morning exercise, and evening exercise. The main outcome is insulin sensitivity determined by a 2-step hyperinsulinemic-euglycemic clamp.
918 studies on the registry are indexed under Prediabetic State; 232 are open to participants now.
This study's planned enrollment of 28 is below the median of 62 across 762 interventional studies indexed under Prediabetic State.
Browse Prediabetic State studies →German Diabetes Center is the lead sponsor of 30 studies on the registry; 8 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Pre-diabetes defined as an isolated impaired glucose tolerance or a combination of impaired glucose tolerance and impaired fasting glucose (values are based on the American Diabetes Association (ADA):
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Behavioral: Timing of exercise
Behavioral: Timing of exercise
Behavioral: Timing of exercise
Behavioral: Timing of exercise
Behavioral: Control
Behavioral: Control
An acute exercise bout of cycling performed in the morning at 9 AM
An acute exercise bout of cycling performed in the morning at at 5 PM
No exercise
Insulin sensitivity
Effect of timed exercise on insulin sensitivity assessed using insulin sensitivity index (reported as M-value: mg x kg-1 x min-1) during an hyperinsulinemic-euglycemic clamp
Time frame: 12 to 24 hours post-exercise intervention
Skeletal muscle metabolites
Effect of timed exercise on skeletal muscle mitochondrial respiration (pmol/mg/s) measured with high resolution respirometry
Time frame: 12 to 24 hours post-exercise intervention
Skeletal muscle clock genes
Effect of timed exercise on quantified DNA measured with quantitative polymerase chain reaction (qPCR)
Time frame: 12 to 24 hours post-exercise intervention
Adipose tissue metabolites
Effect of timed exercise on adipose tissue mitochondrial respiration (pmol/mg/s) measured with high resolution respirometry
Time frame: 12 to 24 hours post-exercise intervention
Adipose tissue clock genes
Effect of timed exercise on quantified DNA measured with quantitative polymerase chain reaction (qPCR)
Time frame: 12 to 24 hours post-exercise intervention
Hepatic glycogen content assessed using 13C Magnetic Resonance Spectroscopy
Effect of timed exercise on hepatic glycogen content, expressed in millimoles per liter (mmol/L) of liver tissue
Time frame: Post-dinner on exercise day
Serum glucose
Effect of timed exercise on serum glucose levels (mg/dL) determined from venous blood draws
Time frame: 12 to 24 hours post-exercise intervention
Serum free fatty acids
Effect of timed exercise on serum free fatty acid levels (mmol/L) determined from venous blood draws
Time frame: 12 to 24 hours post-exercise intervention
Serum triglycerides
Effect of timed exercise on serum triglycerides (mg/dL) determined from venous blood draws
Time frame: 12 to 24 hours post-exercise intervention
Serum cholesterol
Effect of timed exercise on serum cholesterol (mg/dL) determined from venous blood draws
Time frame: 12 to 24 hours post-exercise intervention
Serum insulin
Effect of timed exercise on serum insulin levels (uIU/mL) determined from venous blood draws
Time frame: 12 to 24 hours post-exercise intervention
Resting energy expenditure assessed using indirect calorimetry
Effect of timed exercise on resting energy expenditure, expressed in kilocalories per day (kcal/day)
Time frame: 12 to 24 hours post-exercise intervention
Objective sleep quantity and quality assessed using an actighrapy device
Effect of timed exercise on sleep duration, efficiency, and fragmentation are measured objectively from the actighrapy device
Time frame: The nighttime of exercise intervention day
Liver lipid content measured using ¹H/³¹P Magnetic Resonance Spectroscopy
To assess the difference in liver lipid content in percentage (%) between morning versus evening chronotypes
Time frame: Baseline assessment
Skeletal muscle lipid content measured using ¹H/³¹P Magnetic Resonance Spectroscopy
To assess the difference in skeletal muscle lipid content in percentage (%) between morning versus evening chronotypes
Time frame: Baseline assessment
Body composition expressed as fat mass (kg and %) and fat-free mass (kg) assessed using Bodpod and Bioelectrical Impedance
To assess the difference in body composition between morning versus evening chronotypes
Time frame: Baseline assessment
Maximal aerobic capacity measured using spiroergometry
To assess the difference in maximal aerobic capacity (VO₂max) between morning versus evening chronotypes
Time frame: Baseline assessment
Subjective sleep quality assessed using the Pittsburgh Sleep Quality Index (PSQI)
To assess the difference in subjective sleep quality between morning versus evening chronotypes. Total score range of 1 to 21, higher scores indicating poorer sleep quality
Time frame: Baseline assessment
Level of sleepiness assessed using the Stanford Sleepiness Scale (SSS)
To assess the difference in level of sleepiness between morning versus evening chronotypes. On a 7-point scale, 1 representing feeling alert and 7 indicating being almost in reverie
Time frame: Baseline assessment
Consumption of specific foods or food groups assessed using the DEGS1-Food Frequency Questionnaire (FFQ)
To assess the difference in consumption frequency of specific foods or food groups (expressed as times per week) between morning versus evening chronotypes
Time frame: Baseline assessment
Hedonic hunger assessed using the Power of Food Scale questionnaire
To assess the difference in hedonic hunger between morning versus evening. Mean score of 15 items rated on a 5-point Likert scale (range 1-5). Higher scores indicate greater psychological responsiveness to food cues
Time frame: Baseline assessment
Severity and type of food cravings assessed using the Control of Eating Questionnaire (CoEQ)
To assess the difference in self-reported craving strength between morning versus evening chronotypes. A numeric rating scale ranges from 0 to 10. Higher scores indicate stronger food cravings
Time frame: Baseline assessment
Subjective physical activity levels determined using the International Physical Activity Questionnaire (IPAQ)
To assess subjective physical activity levels (low, moderate, high expressed as MET-minutes/week) between morning versus evening chronotypes
Time frame: Baseline assessment
Cognitive performance assessed using the Sustained Attention to Response Test (SART)
To assess the difference in cognitive performance between morning versus evening chronotypes. Performance is assessed using commission errors (incorrect responses to no-go stimuli), omission errors (missed responses to go stimuli), mean reaction time, and reaction time variability, with higher error rates and greater reaction time variability indicating poorer sustained attention and inhibitory control
Time frame: Baseline assessment
Cognitive performance assessed using the Brief Psychomotor Vigilance Test (PVT-B)
To assess the difference in cognitive performance between morning versus evening chronotypes. Performance is assessed using mean reaction time, number of lapses (reaction times ≥500 ms), and fastest 10% reaction times, with slower reaction times and more lapses indicating reduced vigilant attention and alertness.
Time frame: Baseline assessment
Well-being assessed using the World Health Organization-Five Well-being Index (WHO-5)
To assess the difference in well-being between morning versus evening chronotypes. Scores range from 0 to 25 with higher scores indicating better well-being and psychological health
Time frame: Baseline assessment
Mental health assessed using the Patient Health Questionnaire-9 (PHQ-9)
To assess the difference in mental health between morning versus evening chronotypes. A 9-item self-report questionnaire assessing depressive symptoms over the past two weeks, scored from 0 to 27 with higher scores indicating greater severity of depressive symptoms
Time frame: Baseline assessment
Quality of life assessed using the 36-Item Short Form Survey Instrument (SF-36)
To assess the difference in quality of life between morning versus evening chronotypes. A self-report questionnaire assessing health-related quality of life across eight domains-physical functioning, role limitations due to physical health, bodily pain, general health, vitality, social functioning, role limitations due to emotional problems, and mental health-with scores transformed to a 0-100 scale, where higher scores indicate better health and functioning
Time frame: Baseline assessment
Plan to share: No — Participant data will only be discussed with other researcher on group level. We are not interested in sharing individual participant data.
Start is estimated for Sep 2026; primary completion for Aug 2028, 23 months later.
Of 378 non-industry interventional studies with no phase under Prediabetic State, half reached primary completion within 25 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 39. This study's planned 23 months is close to that.
Counting every sponsor, half of 424 studies reached it within 23 months; a quarter within 11 and three quarters within 37.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
German Diabetes Center