Effects of Interrupting Sedentary Time on Glycemic Control in Older Overweight and Obese Adults

Summary

Increasing physical activity in older adults has important implications for treating obesity related metabolic conditions, however the interaction of aging- and obesity-related declines in physical function may make adding structured exercise particularly challenging for this group. Given these challenges, an alternative prescription to traditional structured exercise, may be short bouts of intermittent walking scattered throughout the day - this may be an effective strategy to increase physical activity, reduce sedentary behavior, and improve glycemic control in overweight/obese older adults. The purpose of this project is to determine how interrupting sedentary time with short bouts of moderate intensity walking affects important metabolic outcomes in older, overweight adults. It would also be of interest to compare the effects of short, frequent interruptions in sedentary behavior to a traditional exercise prescription (continuous 30 min walking bout) on metabolic outcomes (e.g., glycemic control, insulin sensitivity, and 24 h fat oxidation). Thus, the overall aims of the proposed research are to 1) Determine the effect of performing short bouts of moderate-intensity intermittent walking (IW) on glucose and insulin metabolism compared to uninterrupted sitting (US) in older overweight and obese adults. 2) To compare the effects of interrupting sedentary time (IW) vs. a traditional exercise prescription (continuous 30 m walk (CW)) on metabolism.

The investigators hypothesize that interrupting sedentary time with intermittent walking will improve glucose and insulin metabolism compared to uninterrupted sitting and it will be as effective at improving metabolism as a single continuous 30 min walk.

Conditions

• Metabolic Syndrome
• Diabetes
• Aging

Interventions

OTHER

US

US is a 5-hour intervention/condition where participants will be required to sit quietly for 5 consecutive hours.

OTHER

IW

IW is a 24-hour intervention/condition where participants interrupt sedentary time with short 1.5 minute walking bout.

OTHER

CW

CW is a 24-hour intervention/condition where participants perform a 36 minute continuous walking bout and are seated the remainder of the time.

Sponsors & Collaborators

• University of Colorado, Denver

  lead OTHER

Principal Investigators

• Kate Lyden, PhD · University of Colorado, Denver

• Ed Melanson, PhD · University of Colorado, Denver

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

CROSSOVER

Eligibility

Min Age

60 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2013-11-30

Primary Completion

2014-12-31

Completion

2014-12-31

Countries

• United States

Study Locations