Influence of Sedentary Time on Skeletal Muscle Protein Metabolism

Influence of Increased Sedentary Time on Long-term Rates of Skeletal Muscle Protein Synthesis in Young Adults

This study will investigate the influence of increased sedentary time on long-term measures of muscle protein synthesis and metabolic health. The investigators will test the hypothesis that increased time spent in sedentary behaviours will lead to a reduction in long-term measures of muscle protein synthesis and compromised metabolic health.

Study Overview

• Status: Completed
• Conditions: Sedentary Lifestyle
• Intervention / Treatment: Behavioral: 7 days of habitual physical activity followed by 7 days of reduced physical activity

Detailed Description

Sarcopenia, the loss of muscle mass with age, is thought to be accelerated by an inactive, sedentary lifestyle. Increased sedentary time has consistently been associated with lower muscle mass and compromised metabolic health. However, there is currently a lack of direct evidence to support these associations.

Therefore, this study will investigate whether increased sedentary time (reduced step count and exercise cessation) directly influences long-term measures of muscle protein synthesis and metabolic health in young, active adults. Following a 7 day period of normal habitual physical activity, participants will undertake a 7 day period of step reduction and exercise cessation. It is hypothesised that 7 days of increased sedentary time will result in a reduction in long-term rates of muscle protein synthesis and a worsening of metabolic health.

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

Contacts and Locations

Study Locations

• United Kingdom
  • Birmingham, United Kingdom, B15 2TT
    • School of Sport Exercise and Rehabilitation Sciences, University of Birmingham

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Body mass index (18.5-29.99 kg/m2)
• Active - defined as: ≥ 7000 steps per day (assessed during screening) and taking part in regular exercise (defined as participation in ≥ 3 sessions of aerobic and/or resistance exercise type sessions a week for ≥ 6 months prior to recruitment)
• Good general health

Exclusion Criteria:

• Lidocaine allergy
• Hypertension (≥140/90 mmHg)
• Current participation in another clinical study
• Previous participation in this study
• Bleeding disorder/s
• Current or recent smoker
• Past history of substance abuse and/or taking prescription or non-prescription medication (e.g., beta-blockers, insulin or thyroxine) or supplements that may influence normal metabolic responses.
• Participants who have previously (within 5 years of the present study) had 4 or more muscle biopsies obtained from the thigh quadriceps region will be ineligible.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Physical inactivity; Study arm consisting of 7 days of habitual physical activity followed by 7 days of step reduction and exercise cessation.	Behavioral: 7 days of habitual physical activity followed by 7 days of reduced physical activity; Young, active participants will undergo a 7 day period of habitual physical activity followed by a 7 day period of step reduction and exercise cessation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle protein synthesis (FSR %/day)	Long-term muscle protein synthesis (FSR %/day) will be determined using deuterium oxide (D2O) to compare muscle protein synthesis rates over the first 7 day period and the second 7 day period.	0-14 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of fat oxidation at rest (g/min)	Whole body oxygen consumption (VO2, L/min) and carbon dioxide production (VCO2, L/min) at rest will be measured using indirect calorimetry to calculate the rate of fat oxidation at rest (g/min).	For 20 minutes at day 7 and day 14
Rate of fat oxidation during an oral glucose tolerance test (g/min)	Whole body oxygen consumption (VO2, L/min) and carbon dioxide production (VCO2, L/min) following an oral glucose drink will be measured using indirect calorimetry to calculate the rate of fat oxidation during an oral glucose tolerance test (g/min).	At 0, 30, 60, 90 and 120min of the oral glucose tolerance test at day 7 and day 14
Rate of carbohydrate oxidation at rest (g/min)	Whole body oxygen consumption (VO2, L/min) and carbon dioxide production (VCO2, L/min) at rest will be measured using indirect calorimetry to calculate the rate of carbohydrate oxidation at rest (g/min).	For 20 minutes at day 7 and day 14
Rate of carbohydrate oxidation during an oral glucose tolerance test (g/min)	Whole body oxygen consumption (VO2, L/min) and carbon dioxide production (VCO2, L/min) following an oral glucose drink will be measured using indirect calorimetry to calculate the rate of carbohydrate oxidation during an oral glucose tolerance test (g/min).	At 0, 30, 60, 90 and 120min of the oral glucose tolerance test at day 7 and day 14
Blood glucose concentration	Blood glucose concentration will be assessed in blood samples taken during the oral glucose tolerance test.	At 0, 30, 60, 90 and 120min of the oral glucose tolerance test at day 7 and day 14
Blood insulin concentration	Blood insulin concentration will be assessed in blood samples taken during the oral glucose tolerance test.	At 0, 30, 60, 90 and 120min of the oral glucose tolerance test at day 7 and day 14
Blood fatty acid concentration	Blood fatty acid concentration will be assessed in blood samples taken during the oral glucose tolerance test.	At 0, 30, 60, 90 and 120min of the oral glucose tolerance test at day 7 and day 14

Collaborators and Investigators

• Sponsor: University of Birmingham
• Collaborators: Maastricht University
• Investigators: Principal Investigator: Brandon J Shad, BSc, University of Birmingham

Study record dates

Study Major Dates

• Study Start: March 1, 2016
• Primary Completion (Actual): April 1, 2017
• Study Completion (Actual): February 1, 2018

Study Registration Dates

• First Submitted: December 2, 2015
• First Submitted That Met QC Criteria: December 3, 2015
• First Posted (Estimate): December 8, 2015

Study Record Updates

• Last Update Posted (Actual): October 11, 2018
• Last Update Submitted That Met QC Criteria: October 10, 2018
• Last Verified: October 1, 2018

More Information

Terms related to this study

• Other Study ID Numbers: ERN_15-1238