Individual Variability of Coronary Heart Disease Risk Markers and Sleep Responses to Exercise
- Conditions
- Coronary Heart DiseaseBlood PressureArterial StiffnessCardiovascular Risk FactorSleep
- Interventions
- Behavioral: Exercise
- Registration Number
- NCT05022498
- Lead Sponsor
- Loughborough University
- Brief Summary
The aim of this study is to examine the reproducibility of postprandial coronary heart disease (CHD) risk marker and sleep responses to acute exercise bouts and to quantify the magnitude of individual variability in responses using a replicated crossover design. Healthy, recreationally active men will complete two identical rest control and two identical exercise (60 min at 60% maximum oxygen uptake) conditions in randomised sequences. Fasting and postprandial venous blood samples, arterial blood pressure and arterial stiffness measurements will be taken at pre-determined intervals, and sleep duration and quality will be assessed. Reproducibility and individual variability will be examined using bivariate correlations and linear mixed modelling.
- Detailed Description
Single bouts of exercise reduce circulating concentrations of postprandial triacylglycerol - an established independent risk marker for coronary heart disease (CHD). The exercise-induced reduction in postprandial triacylglycerol concentrations has been shown to coincide with transient changes in other CHD risk markers, including reductions in postprandial insulin, interleukin-6, arterial stiffness and resting arterial blood pressure, and exercise may also promote sleep duration and quality. Individual variability in these responses is suspected but has not been examined using robust designs and appropriate statistical models. A recent approach to quantify individual variability in the intervention response involves quantifying the participant-by-condition interaction from replicated intervention and comparator arms. Using this approach (the replicated crossover design), the present study will (i) examine whether the postprandial CHD risk marker and sleep responses to acute exercise are reproducible on repeated occasions; and (ii) determine whether there is true individual variability in postprandial CHD risk marker and sleep responses to acute exercise.
A total of 20 healthy, recreationally active men will be recruited. Participants will undertake a preliminary measures visit (visit 1) to confirm eligibility, to undergo anthropometric measurements and to determine maximum oxygen uptake. Participants will complete four, 2-day experimental conditions in randomised sequences separated by at least one week: two identical control and two identical exercise conditions. On day 1 (visits 2, 4, 6 and 8), participants will arrive fasted at 08:00 and a baseline blood sample, blood pressure and arterial stiffness measurement will be taken. Participants will consume a standardised high fat breakfast at 08:45 (0 h) and lunch at 12:45 (4 h). A second arterial stiffness measurement will be taken at 16:45 (8 h). The two control and two exercise conditions will be identical, except that participants will be asked to exercise on the treadmill for 60 minutes at 60% of their maximum oxygen uptake at 15:15 (6.5 h) in both exercise conditions. On day 2 (visits 3, 5, 7 and 9), participants will arrive fasted at 08:00 and will rest in the laboratory throughout the day in the two control and two exercise conditions. Participants will consume a standardised breakfast at 08:45 (0 h) and a standardised lunch at 12:45 (4 h). Venous blood samples will be collected at 0, 0.5, 1, 2, 3, 4, 4.5, 5, 6, 7 and 8 h. Resting arterial blood pressure will be measured at hourly intervals. Arterial stiffness will be measured at 0, 2.5 and 5 h. Sleep duration and quality will be assessed for three nights before and two nights after visits 3, 5, 7 and 9 using a triaxial actigraphy watch.
Reproducibility and individual variability will be explored by correlating the two sets of response differences between exercise and control conditions. Within-participant covariate-adjusted linear mixed models will be used to quantify participant-by-condition interactions. It is hypothesised that (i) control-adjusted postprandial CHD risk marker and sleep responses to acute exercise will be reproducible; and (ii) true interindividual variability will exist in postprandial CHD risk marker and sleep responses to acute exercise beyond any random within-subject variation.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 20
- 18 to 45-year-old men;
- Be able to run continuously for 1 hour;
- Body mass index between 18.5 and 29.9 kg/m2;
- No known contradictions to maximal exertion exercise (e.g., recent musculoskeletal injury, congenital heart disease).
- Musculoskeletal injury that has affected normal ambulation within the last month;
- Uncontrolled exercise-induced asthma;
- Coagulation or bleeding disorders;
- Heart conditions;
- Diabetes (metabolism will be different to non-diabetics potentially skewing the data);
- Taking any medication that might influence fat metabolism, blood glucose or appetite;
- Smoking (including vaping);
- Dieting or restrained eating behaviours;
- Weight fluctuation greater than 3 kg in the previous 3 months to study enrolment;
- Presence of any diagnosed sleeping disorder;
- A food allergy.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Exercise 2 Exercise Participants will complete 60 min of treadmill exercise on day 1 (15:15-16:15). Participants will rest in the laboratory for the remainder of day 1 and throughout day 2 (08:00-17:00). A high fat breakfast and lunch will be consumed on both days at pre-determined intervals. Exercise 1 Exercise Participants will complete 60 min of treadmill exercise on day 1 (15:15-16:15). Participants will rest in the laboratory for the remainder of day 1 and throughout day 2 (08:00-17:00). A high fat breakfast and lunch will be consumed on both days at pre-determined intervals.
- Primary Outcome Measures
Name Time Method Plasma triacylglycerol concentration Day 1: fasted; Day 2: fasted (0 hours), 0.5 hours, 1 hours, 2 hours, 3 hours, 4 hours, 4.5 hours, 5 hours, 6 hours, 7 hours and 8 hours Fasted plasma triacylglycerol concentration on day 1 and day 2. Time-averaged total area under the curve for triacylglycerol on day 2 in response to exercise and/or feeding.
- Secondary Outcome Measures
Name Time Method Plasma total cholesterol concentration Day 1: fasted; Day 2: fasted Fasted plasma total cholesterol concentration on day 1 and day 2.
Plasma C-reactive protein concentration Day 1: fasted; Day 2: fasted Fasted plasma C-reactive protein concentration on day 1 and day 2.
Apolipoprotein E Day 1: fasted (baseline) Apolipoprotein E genotype at baseline.
Plasma high-density lipoprotein cholesterol concentration Day 1: fasted; Day 2: fasted Fasted plasma high-density lipoprotein cholesterol concentration on day 1 and day 2.
Plasma low-density lipoprotein cholesterol concentration Day 1: fasted; Day 2: fasted Fasted plasma low-density lipoprotein cholesterol concentration on day 1 and day 2.
Sleep efficiency 20 nights (5 nights per condition; three nights before and two nights after visits 3, 5, 7 and 9) Total sleep time expressed as a percentage of time in bed.
Resting arterial blood pressure Day 1: fasted; Day 2: fasted (0 hours), 1 hours, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours and 8 hours Fasted resting systolic and diastolic blood pressure on day 1 and day 2. Time-averaged total area under the curve for systolic and diastolic blood pressure on day 2 in response to exercise and/or feeding.
Resting pulse wave analysis Day 1: fasted (0 hours), 8 hours; Day 2: fasted (0 hours), 2.5 hours, 5 hours. Time-course of resting pulse wave analysis in response to exercise and/or feeding on day 1 and day 2.
Resting pulse wave velocity Day 1: fasted (0 hours), 8 hours; Day 2: fasted (0 hours), 2.5 hours, 5 hours. Time-course of resting pulse wave velocity in response to exercise and/or feeding on day 1 and day 2.
Actual wake time 20 nights (5 nights per condition; three nights before and two nights after visits 3, 5, 7 and 9) Total time awake after the first sleep period.
Sleep onset latency 20 nights (5 nights per condition; three nights before and two nights after visits 3, 5, 7 and 9) Total time from 'lights out' to the first sleep epoch.
Plasma glucose concentration Day 1: fasted; Day 2: fasted (0 hours), 0.5 hours, 1 hours, 2 hours, 3 hours, 4 hours, 4.5 hours, 5 hours, 6 hours, 7 hours and 8 hours Fasted plasma glucose concentration on day 1 and day 2. Time-averaged total area under the curve for glucose on day 2 in response to exercise and/or feeding.
Plasma insulin concentration Day 1: fasted; Day 2: fasted (0 hours), 0.5 hours, 1 hours, 2 hours, 3 hours, 4 hours, 4.5 hours, 5 hours, 6 hours, 7 hours and 8 hours Fasted plasma insulin concentration on day 1 and day 2. Time-averaged total area under the curve for insulin on day 2 in response to exercise and/or feeding.
Time in bed 20 nights (5 nights per condition; three nights before and two nights after visits 3, 5, 7 and 9) Total time in bed between 'lights out' to 'lights on'.
Total sleep time 20 nights (5 nights per condition; three nights before and two nights after visits 3, 5, 7 and 9) Total time asleep between 'lights out' to 'lights on'.
Sleep fragmentation index 20 nights (5 nights per condition; three nights before and two nights after visits 3, 5, 7 and 9) Number of times that sleep is terminated after one minute expressed as a percentage of the total sleep time.
Trial Locations
- Locations (1)
Loughborough University
🇬🇧Loughborough, United Kingdom