Curves 30/30 Study (C-30)

Effects of Repeated Short-Term Diets on Weight Loss in Women Participating in the Curves Fitness Program

The purpose of this study is to determine whether following a high carbohydrate/low fat diet or high protein/low fat diet for 30-days several times during six months of participating in the Curves fitness and diet program with or without dietary calcium supplementation promotes stepwise reductions in body weight, improvements in body composition, and/or improvements in markers of fitness and health.

Study Overview

• Status: Completed
• Conditions: Weight Loss
• Intervention / Treatment: Dietary supplement: Curves Calcium; Dietary supplement: Placebo

Detailed Description

The Curves International fitness and weight loss program has become a very popular means of promoting health and fitness among women. The program involves a 30-minute circuit training program and a weight management program involving periods of moderate caloric restriction (1,200 to 1,600 calories per day) followed by short periods of higher caloric intake (2,600 calories per day). The program is designed to promote a gradual reduction in body fat while increasing strength and muscle mass/tone. Researchers in the Exercise & Sport Nutrition Laboratory (ESNL) at Texas A&M University have conducted an extensive study on the effectiveness and safety of the Curves fitness and diet program. Results of this initial study have shown that the program promotes weight loss, improves markers of health, and improves fitness. However, we feel that the program may be even more effective with some additional nutritional interventions. Calcium has been shown to slow bone loss and more recently has been found to help promote fat loss. If this is the case, supplementing the diet with calcium may promote greater benefits in women participating in the Curves fitness and diet program. The purpose of this study is to determine whether following a high carbohydrate/low fat diet or high protein/low fat diet for 30-days several times during six months of participating in the Curves fitness and diet program with or without dietary calcium supplementation promotes stepwise reductions in body weight, improvements in body composition, and/or improvements in markers of fitness and health.

• Study Type: Interventional
• Enrollment (Actual): 57
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Texas
    • College Station, Texas, United States, 77843
      • Exercise & Sport Nutrition Laboratory

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Participant is female;
• Participant is post-menopausal;
• Participant is between the ages of 18 and 45;
• Participant is sedentary, overweight (BMI > 27) and post-menopausal;

Exclusion Criteria:

• Participant has any metabolic disorders including known electrolyte abnormalities, heart disease, arrhythmias, diabetes, or thyroid disease;
• Participant has a history of hypertension, hepatorenal, musculoskeletal, autoimmune or neurological disease;
• Participant is taking thyroid, hyperlipidemic, hypoglycemic, anti-hypertensive or androgenic medications;
• Participant has taken ergogenic levels of nutritional supplements that may affect muscle mass (i.e., creatine, HMB, etc.), anabolic/catabolic hormone levels (i.e., androstenedione, DHEA, etc.) or weight loss (i.e., ephedra, thermogenics, etc.) within three months prior to the start of the study;
• Participant is consistently taking 500 mg or more of a Calcium supplement per day;
• Participant is receiving Hormone Replacement Therapy (HRT);
• Participant is involved in a planned exercise program within 3 - 6 months prior to the start of the study;
• Participant has lost > 20 lbs. within the last 3 - 6 months;

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Control; No diet or exercise intervention	Dietary supplement: Curves Calcium; Dietary Supplement: Curves Calcium Curves Essential Bio-Available Calcium (providing 800 mg/d of calcium [as calcium citrate malate and calcium citrate], 400 IU of Vitamin D, 300 mg/d of magnesium, 4 mg/d of zinc, 2 mg/d of copper, 2 mg/d of manganese, 198 mg/d of potassium, 100 mg/d of trace mineral complex, and 2 mg/d of boron); Dietary supplement: Placebo; Dextrose Placebo
Experimental: No Diet plus Exercise; No diet, exercise only intervention	Dietary supplement: Curves Calcium; Dietary Supplement: Curves Calcium Curves Essential Bio-Available Calcium (providing 800 mg/d of calcium [as calcium citrate malate and calcium citrate], 400 IU of Vitamin D, 300 mg/d of magnesium, 4 mg/d of zinc, 2 mg/d of copper, 2 mg/d of manganese, 198 mg/d of potassium, 100 mg/d of trace mineral complex, and 2 mg/d of boron); Dietary supplement: Placebo; Dextrose Placebo
Experimental: High Protein Diet plus Exercise; High protein diet and exercise intervention	Dietary supplement: Curves Calcium; Dietary Supplement: Curves Calcium Curves Essential Bio-Available Calcium (providing 800 mg/d of calcium [as calcium citrate malate and calcium citrate], 400 IU of Vitamin D, 300 mg/d of magnesium, 4 mg/d of zinc, 2 mg/d of copper, 2 mg/d of manganese, 198 mg/d of potassium, 100 mg/d of trace mineral complex, and 2 mg/d of boron); Dietary supplement: Placebo; Dextrose Placebo
Experimental: High Carbohydrate Diet plus Exercise; High carbohydrate diet and exercise intervention	Dietary supplement: Curves Calcium; Dietary Supplement: Curves Calcium Curves Essential Bio-Available Calcium (providing 800 mg/d of calcium [as calcium citrate malate and calcium citrate], 400 IU of Vitamin D, 300 mg/d of magnesium, 4 mg/d of zinc, 2 mg/d of copper, 2 mg/d of manganese, 198 mg/d of potassium, 100 mg/d of trace mineral complex, and 2 mg/d of boron); Dietary supplement: Placebo; Dextrose Placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Composition: Body Fat	Changes in body composition (% body fat) obtained via DXA and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Body Composition: Fat Free Mass	Changes in body composition (fat free mass) obtained via DXA and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Body Composition: Bone Mass	Changes in body composition (bone mass) obtained via DXA and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Body Composition: Fat Mass	Changes in body composition (fat mass) obtained via DXA and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Body Composition: Lean Mass	Changes in body composition (lean mass) obtained via DXA and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Body Composition: Body Weight	Changes in body composition (body weight) obtained via DXA and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Energy Homeostasis: Resting Energy Expenditure (REE)	Changes in REE obtained via metabolic cart and expressed in absolute (kcal/d) and relative terms kcals/kg/d) and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Energy Homeostasis: Respiratory Exchange Ratio (RER)	Changes in RER as an indicator of carbohydrate and fat oxidation analyzed with related resting energy expenditure outcome measures via General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Muscular Strength: 1 Repetition Maximum (1 RM) Bench Press	Changes in bench press 1 RM obtained from a bench press test and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 3, and 6 months
Muscular Strength: 1 Repetition Maximum (1 RM) Leg Press	Changes in bench press 1 RM obtained from a leg press test and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 3, and 6 months
Muscular Endurance: 80% of 1 Repetition Maximum (1 RM) Bench Press Endurance Test	Changes in total repetitions at 80% of 1 RM obtained from a bench press test and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 3, and 6 months
Muscular Endurance: 80% of 1 Repetition Maximum (1 RM) Leg Press Endurance Test	Changes in total repetitions at 80% of 1 RM obtained from a leg press test and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 3, and 6 months
Cardiac Variable: Resting Electrocardiogram (ECG)	Changes in resting ECG obtained via electrodes and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 3, and 6 months
Cardiac Variable: Graded Exercise Test (GXT)	Changes in exercise capacity obtained via a treadmill test and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 3, and 6 months
Hemodynamic Variable: Resting Heart Rate (RHR)	Changes in resting heart rae (RHR) obtained via a blood pressure meter and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Hemodynamic Variable: Resting Systolic Blood Pressure (SBP)	Changes in resting systolic blood pressure (mmHg) analyzed with related resting hemodynamic outcome measures via General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Hemodynamic Variable: Resting Diastolic Blood Pressure (DBP)	Changes in resting diastolic blood pressure (mmHg) analyzed with related resting hemodynamic outcome measures via General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Anthropometric Measures: Waist Circumference	Changes in waist circumference obtained via tape measure and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Anthropometric Measures: Hip Circumference	Changes in hip circumference obtained via tape measure and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Anthropometric Measures: Waist to Hip Ratio	Changes in the ratio of waist to hip (waist/hip circumference) analyzed with related anthropometric outcome measures via General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Fasting Glucose	Changes in glucose obtained via venous blood draws and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Lipid Panel: Cholesterol	Changes in cholesterol obtained via venous blood draws and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Lipid Panel: HDL Cholesterol	Changes in HDL cholesterol obtained via venous blood draws and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Lipid Panel: Cholesterol to HDL Ratio	Changes in cholesterol to HDL ratio obtained via venous blood draws and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Lipid Panel: LDL Cholesterol	Changes in LDL cholesterol obtained via venous blood draws and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months
Lipid Panel: Triglycerides	Changes in triglycerides obtained via venous blood draws and analyzed by General Linear Model multivariate and univariate analyses with repeated measures and mean change from baseline with 95% confidence intervals (CI's)	Measured prior to supplementation (Pre), and after 1, 2, 3, 4, 5 and 6 months

Collaborators and Investigators

• Sponsor: Texas A&M University
• Collaborators: Curves International

Study record dates

Study Major Dates

• Study Start: May 18, 2009
• Primary Completion (Actual): May 3, 2012
• Study Completion (Actual): May 3, 2012

Study Registration Dates

• First Submitted: April 9, 2020
• First Submitted That Met QC Criteria: April 9, 2020
• First Posted (Actual): April 14, 2020

Study Record Updates

• Last Update Posted (Actual): April 15, 2020
• Last Update Submitted That Met QC Criteria: April 13, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Body Weight Changes; Weight Loss; Physiological Effects of Drugs; Calcium-Regulating Hormones and Agents; Calcium
• Other Study ID Numbers: IRB2008-0480

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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