Clinical trial NCT03952000: Influence of Prior Walking on Postprandial Metabolism in Centrally Obese Men
Official title: Influence of Prior Walking on Endothelial Function and Coronary Heart Disease Risk Markers in Centrally Obese South Asian and White European Men
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Diabetes Mellitus, Type 2
Cardiovascular Diseases
Endothelial Dysfunction
Insulin Resistance
Oxidative Stress
Lead sponsor: Loughborough University
Sponsor class: OTHER
Collaborators: name: University Hospitals, Leicester
First posted: 2019-05-16
Enrollment: 30
Sex: MALE
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: PREVENTION

Brief summary: The present study will investigate the effect of prior walking on postprandial metabolism and endothelial function in centrally obese South Asian and White European men.

Participants will complete two, 2-day trials in a random, crossover design separated by at least a week.

On day 1, participants will either rest or complete a 60 minute walk at 60% maximal oxygen uptake. On day 2, participants will arrive at 08:00 having fasted overnight and a baseline venous blood sample and endothelial function measurement will be taken. Participants will consume a high-fat breakfast and lunch and 12 subsequent venous blood samples will be taken throughout the day at standardised intervals to measure a variety of coronary heart disease risk markers. A second endothelial function measurement will be completed 2 hours after the breakfast. Blood pressure will be measured every hour.

It is expected that the South Asian participants will have impaired metabolism and endothelial function compared to their European counterparts but the bout of exercise performed on day 1 will mitigate these responses.

Detailed description: South Asians have a higher-than-average risk of coronary heart disease. The reasons for this are unclear, but physical inactivity and/or poor responsiveness to exercise may play a role. It is important to understand the effect of exercise on endothelial function and coronary heart disease risk markers in the hope that exercise can be prescribed as an effective treatment to mitigate endothelial dysfunction and the risk of heart disease.

Previous research from the investigators' laboratory has indicated that postprandial metabolism is impaired in South Asian men, but this, and other coronary heart disease risk markers, can be improved with acute exercise. However, the previous research was conducted in apparently healthy South Asian and White European men. The investigators now wish to quantify and compare the coronary heart disease risk marker and endothelial function response to acute exercise in centrally obese South Asian and White European individuals who are at a higher risk for diabetes and cardiovascular disease.

On visit 1, participants will attend the laboratory to undergo preliminary assessments and to be familiarised with the laboratory environment and study procedures. Specifically, health status, habitual physical activity, dietary habits and anthropometric data (height, weight, waist and hip circumference, body fat) will be collected. A HbA1c test will be performed to check participants are not diabetic. The modified Bruce Treadmill test will be performed to predict maximal oxygen uptake.

On visit 2, participants will undergo a magnetic resonance imaging (MRI) scan to quantify regional body composition comprising abdominal subcutaneous adipose tissue, visceral adipose tissue, liver fat percentage, thigh intramuscular adipose tissue and thigh muscle volume.

On visits 3-6 participants will complete two, 2-day trials in a random, crossover design separated by at least 1 week. On day 1 of both trials, participants will arrive fasted at 08:00 and a baseline blood sample, blood pressure and endothelial function measurement will be taken. Participants will consume a standardised high fat breakfast at 09:00 and lunch at 13:00. At 15:30 the participants will walk for 60 minutes at 60% maximal oxygen uptake and complete a second endothelial function measurement at 16:45. Participants will leave the laboratory with a standardised evening meal to consume before 22:00. The control trial will be the same, except no exercise will be performed.

On day 2, participants will arrive at 08:00 having fasted overnight for 10h (except plain water). A cannula will be inserted into the antecubital vein for collection of venous blood samples. Blood pressure will be measured at 08:00 (0h) and again at hourly intervals throughout the day. Endothelial function will measured at 08:15 (0.25h) and again at 3h. At 0h, a fasting blood sample will be collected. Subsequent venous blood samples will be collected at 1.5, 1.75, 2, 3, 4, 5, 5.5, 5.75, 6, 7, 8 and 9h. Participants will consume a standardised high fat breakfast at 1h and a standardised high fat lunch at 5h. The meals consist of 57% fat, 32% carbohydrate and 11% protein. The meals provide 14.3 kcal per kg of body mass.

Participants will rest in the laboratory throughout day 2 of both the exercise and control trials.

Eligibility criteria: Inclusion Criteria:

* 18 to 60 year old South Asian and White European men;
* Centrally obese (waist circumference \>90cm for South Asians, \>94cm for White Europeans);
* Weight stable for the past 3 months;
* Non-smokers;
* No known contradictions to maximal exertion exercise.

Exclusion Criteria:

* Musculoskeletal injury that has affected normal ambulation within the last month;
* Congenital heart disease;
* Any muscle or bone injuries that do not allow them to walk on a treadmill;
* Uncontrolled exercise-induced asthma;
* Coagulation or bleeding disorders;
* Diabetes (metabolism will be different to non-diabetics potentially skewing the data);
* Taking any medication that might influence fat metabolism;
* Taking any medication that might influence blood glucose (e.g., insulin for diabetes);
* Heart conditions;
* Smoking;
* Dieting or restrained eating behaviours;
* Weight fluctuation greater than 3 kg in the previous 3 months to study enrolment;
* A food allergy.

Primary outcomes:
measure: Triacylglycerol changes in response to exercise and feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 1.5hours, 1.75hours, 2hours, 3hours, 4hours, 5hours, 5.5hours, 5.75hours, 6hours, 7hours, 8hours and 9hours.
measure: Endothelial function changes in response to exercise and feeding
timeFrame: Day 1 fasting and 8.75hours. Day 2 fasting and 2.5hours.
Secondary outcomes:
measure: Glucose changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 1.5hours, 1.75hours, 2hours, 3hours, 4hours, 5hours, 5.5hours, 5.75hours, 6hours, 7hours, 8hours and 9hours.
measure: Blood pressure changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point) and 1hours, 2hours, 3hours, 4hours, 5hours, 6hours, 7hours, 8hours and 9hours.
measure: Total cholesterol
timeFrame: Day 1 fasting. Day 2 fasting.
measure: Insulin changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 1.5hours, 2hours, 4hours, 5hours, 5.5hours, 7hours, 8hours.
measure: High-density lipoprotein cholesterol
timeFrame: Day 1 fasting. Day 2 fasting.
measure: Low-density lipoprotein cholesterol
timeFrame: Day 1 fasting. Day 2 fasting.
measure: Non-esterified fatty acids changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 1.5hours, 2hours, 4hours, 5hours, 5.5hours, 7hours and 9hours.
measure: Interleukin-6 changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 3hours, 6hours and 8hours.
measure: C-Reactive protein changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 3hours, 6hours and 8hours.
measure: Tumor Necrosis Factor concentrations
timeFrame: Day 1 fasting. Day 2 fasting.
measure: Peroxiredoxin-4 changes in response to exercise and/or feeding
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 3hours, 6hours and 8hours.
measure: Superoxide dismutase 3
timeFrame: Day 1 fasting. Day 2 fasting (0 hour point), 3hours, 6hours and 8hours.
Other outcomes:
Locations:
city: Loughborough
country: United Kingdom
facility: National Centre for Sport and Exercise Medicine, Loughborough University
Study officials:
affiliation: Loughborough University
name: David Stensel
role: PRINCIPAL_INVESTIGATOR
References:
citation: Arjunan SP, Deighton K, Bishop NC, King J, Reischak-Oliveira A, Rogan A, Sedgwick M, Thackray AE, Webb D, Stensel DJ. The effect of prior walking on coronary heart disease risk markers in South Asian and European men. Eur J Appl Physiol. 2015 Dec;115(12):2641-51. doi: 10.1007/s00421-015-3269-7. Epub 2015 Oct 5.
citation: Arjunan SP, Bishop NC, Reischak-Oliveira A, Stensel DJ. Exercise and coronary heart disease risk markers in South Asian and European men. Med Sci Sports Exerc. 2013 Jul;45(7):1261-8. doi: 10.1249/MSS.0b013e3182853ecf.