Effects of Physical Inactivity on Insulin Sensitivity, Appetite, Energy Balance, and Cardiovascular Responses in Humans.

Short-term Effects of Physical Inactivity on Insulin Sensitivity, Appetite, Energy Balance, and Cardiovascular Responses in Healthy Humans.

Physical inactivity is a significant predictor of major non-communicable diseases such as type 2 diabetes (7%), cardiovascular disease (6%), musculoskeletal disorders and some cancers, and has been proposed to be the 4th leading cause of death worldwide. Reduced physical activity leads to an impaired function of the hormone insulin and increased adiposity. Thus, the elimination of physical inactivity would remove between 6% and 10% of the major non-communicable diseases and increase life expectancy. The aim of the study is to investigate the effects of a short-term (2-day) period of reduced physical activity, with and without a proportional decrease in energy intake, on the action of insulin to regulate blood sugar fluctuations, appetite, and cardiovascular parameters (heart rate, cardiac output, stroke volume, blood flow, arterial blood pressure, peripheral vascular resistance) in response to food ingestion.

Study Overview

• Status: Completed
• Conditions: Sedentary Behavior
• Intervention / Treatment: Other: Control; Other: SIT+E; Other: SIT=E

• Study Type: Interventional
• Enrollment (Actual): 8
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Nottingham, United Kingdom
    • University of Nottingham

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Non-smoking
• Males and females
• Age (18-35 years old)
• Body mass index (BMI) of 18-27 kg/m2
• Waist circumference <94cm for males and <80cm for females
• Ability to give informed consent

Exclusion Criteria:

• Smoking
• Any metabolic (e.g. diabetes), endocrine (e.g. hyperthyroidism) or cardiovascular (e.g. heart or blood) abnormalities including hypertension or heart failure
• Clinically significant abnormalities on screening including ECG abnormalities
• Taking routine medication that may alter cardiovascular function and blood flow (e.g. blood pressure-lowering drugs or drugs that cause hypertension)
• Well trained individuals with PAL>2.00; on an energy-restricted diet or seeking to lose weight
• High alcohol consumption (<3-4 units/d for men; <2-3 units/d for women)
• Females who are pregnant or lactating; self-reported allergy, intolerance or strong dislike of foods or drinks to be offered for the test breakfast, pasta meal or during the intervention period
• Beck Depression Inventory score >10 and Eating Attitudes Test (EAT-26) score >20 as self-reported markers of symptoms and concerns characteristic of depression and eating disorders, respectively.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Control; 2 consecutive days of standardised daily levels of moderate physical activity (PAL=1.85 reflecting their habitual levels), and matched energy (food) intake	Other: Control; Normal physical activity and standard energy intake
Experimental: SIT+E; 2 consecutive days of reduced physical activity induced by prolonged periods of sitting (PAL=1.4) whilst maintaining the level of food intake prescribed in the Control trial, thus creating a positive energy balance	Other: SIT+E; Reduced physical activity and standard energy intake
Experimental: SIT=E; 2 consecutive days of reduced physical activity induced by prolonged periods of sitting (PAL=1.4) whilst reducing food intake to match the reduction in energy expenditure induced by inactivity, thus maintaining energy balance	Other: SIT=E; Reduced physical activity and reduced energy intake

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The incremental area under curve for Insulin	The incremental area under curve for Insulin will be calculated using samples collected at 20 minute intervals between baseline and three hours	Over three hours from baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The incremental area under curve for arterialized whole blood glucose	The incremental area under curve for arterialized whole blood glucose will be calculated using samples collected at 10 minute intervals between baseline and four hours	Over four hours from baseline

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
The incremental area under curve for free fatty acids	The incremental area under curve for free fatty acids will be calculated using samples collected at 20 minute intervals between baseline and three hours	Over three hours from baseline
The incremental area under curve for Triglycerides	The incremental area under curve for Triglycerides will be calculated using samples collected at 20 minute intervals between baseline and three hours	Over three hours from baseline
The incremental area under curve for Ghrelin	The incremental area under curve for Ghrelin will be calculated using samples collected at one hour intervals between baseline and four hours	Over four hours from baseline
The incremental area under curve for composite satiety score	Composite satiety score will be calculated using 100mm visual analogue score ratings of satiety, fullness, hunger, desire to eat and prospective food consumption collected every 20 minutes between baseline and four hours.	Over four hours from baseline
Weight of consumption of a pasta meal three hours after baseline	Weight of pasta consumed from a bowel refilled prior to being empty until participants feel comfortably full	Three hours post baseline
The incremental area under curve for cardiovascular parameters	The incremental area under curve for mean blood pressure,cardiac output, stroke volume, peripheral resistance, heart rate, systolic blood pressure and diastolic blood pressure continuously over three hours from baseline using Finometer	Over three hours from baseline
The incremental area under curve for limb blood flow	The incremental area under curve for limb blood flow measured at 30 minute intervals between baseline and three hours using venous occlusion plethysmography	Over three hours from baseline

Collaborators and Investigators

• Sponsor: University of Nottingham

Study record dates

Study Major Dates

• Study Start (Actual): October 20, 2017
• Primary Completion (Actual): March 13, 2020
• Study Completion (Actual): March 13, 2020

Study Registration Dates

• First Submitted: November 19, 2019
• First Submitted That Met QC Criteria: November 19, 2019
• First Posted (Actual): November 21, 2019

Study Record Updates

• Last Update Posted (Actual): March 30, 2020
• Last Update Submitted That Met QC Criteria: March 27, 2020
• Last Verified: November 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Hyperinsulinism; Insulin Resistance
• Other Study ID Numbers: I200317

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: only anonymised individual personal data will be shared, upon specific request from other researchers, for example, in order to undertake a meta analysis

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No