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

University of Nottingham

Status: Completed

Conditions: Sedentary Behavior

Treatments: Other: SIT=E; Other: SIT+E; Other: Control

Study type: Interventional

Funder types: Other

Identifiers

NCT04172090

I200317

Details and patient eligibility

About

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.

Enrollment: 8 patients

Sex: All

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

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.

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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8 participants in 3 patient groups

Control

Other group

Description:

2 consecutive days of standardised daily levels of moderate physical activity (PAL=1.85 reflecting their habitual levels), and matched energy (food) intake

Treatment:

Other: Control

SIT+E

Experimental group

Description:

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

Treatment:

Other: SIT+E

SIT=E

Experimental group

Description:

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

Treatment:

Other: SIT=E