"We Walk": Impact of Exercise Dose on Health Outcomes Among Women Ages 60-75

NCT ID: NCT01722136

Last Updated: 2019-04-19

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 72 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-08-31
• Study Completion Date: 2015-06-30

Brief Summary

The overall goal is to determine whether any energy expenditure compensation in response to 16 weeks of aerobic exercise at a higher-dose is greater compared to a lower-dose intervention in older women, and to begin to investigate underlying physiological mechanisms that influence energy expenditure changes in older women.

Detailed Description

The overall goal is to determine whether any energy expenditure compensation in response to 16 weeks of aerobic exercise at a higher-dose is greater compared to a lower-dose intervention in older women, and to begin to investigate underlying physiological mechanisms that influence energy expenditure changes in older women. Changes in all components of energy expenditure, as well as concentrations of plasma leptin and serum free T3, in response to the two different exercise programs (14 and 8 kcal/kg body weight weekly, 60-65% VO2max, 4 days/wk) will be compared in older, non-obese women (60-75 yrs, BMI=18-30 kg/m2).

Specific Aim 1: To determine whether differential changes in total daily energy expenditure and its components occur in older women in response to two exercise programs of different doses. State-of-the-art methods will be used (total daily energy expenditure by doubly labeled water; non-exercise activity thermogenesis using Physical Activity Monitoring System; resting metabolic rate and thermic effect of food via indirect calorimetry).

Primary Hypothesis: Due to a greater decline in NEAT, women will exhibit a smaller increase in total daily energy expenditure in response to the higher-dose, compared to the lower-dose, exercise program, despite greater increases in resting metabolic rate and thermic effect of food.

Specific Aim 2: To explore whether differential changes occur in plasma leptin and serum free triiodo-L-thyronine (free T3) concentrations in older women in response to 16-week aerobic exercise programs of two different doses.

We hypothesize that in response to the higher-dose exercise program, women will exhibit larger decreases in plasma leptin and serum free T3 concentrations, compared to the lower-dose exercise program.

We will also determine whether women exhibit greater improvements in plasma lipids, insulin sensitivity (using homeostasis model assessment, HOMA, score), blood pressure, and aerobic fitness in response to the higher-dose, compared to the lower-dose, exercise program.

Conditions

Condition

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: NONE

Study Groups

Low Dosage

Exercise dose of 8kcal/kg/week

Group Type: EXPERIMENTAL

Low Dosage

Intervention Type: BEHAVIORAL

Exercise dose of 8kcal/kg/week

High Dosage

Exercise dose 14kcal/kg/week

Group Type: EXPERIMENTAL

High Dosage

Intervention Type: BEHAVIORAL

Exercise dose of 14kcal/kg/week

Interventions

Low Dosage

Exercise dose of 8kcal/kg/week

Intervention Type: BEHAVIORAL

High Dosage

Exercise dose of 14kcal/kg/week

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• BMI 18-30
• Sedentary (exercising less than 20 minutes no more than 3 times per week)
• Non-smoking
• Weight stable (+/- 5%) over past 3 months

Exclusion Criteria

• Self-reported cardiovascular disease
• Additional self-reported medical conditions
• Medications known to affect metabolism
• Excess caffeine use
• Self-reported contradictions according to ACSM
• Unwillingness to provide informed consent

• Minimum Eligible Age: 60 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

University of South Carolina

OTHER

Sponsor Role: lead

Responsible Party

Xuewen Wang

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Xuewen Wang, PhD, MEd, BM

Role: PRINCIPAL_INVESTIGATOR

University of South Carolina

Locations

Public Health Research Center University of South Carolina

Columbia, South Carolina, United States

Countries

United States

Related Links

http://wewalk.sc.edu

Brief description of study for potential participants

Other Identifiers

Pro00016306

Identifier Type: -

Identifier Source: org_study_id