Increased Calorie Intake to Reverse Energy Deficiency in Exercising Women: Impact on Bone and Menstrual Cyclicity

The Pennsylvania State University (PENNSTATE)

Status: Completed

Conditions: Menstrual Irregularity

Treatments: Behavioral: EAMD+Calories

Study type: Interventional

Funder types: Other; Other U.S. Federal agency

Identifiers

NCT00392873

15353

Details and patient eligibility

About

The purpose of this study is to examine the effects of increased food intake on the menstrual cycle and bone health in physically active women who have irregular or absent menstrual cycles. This study will examine whether a 12 month period of increased food intake will cause menstrual cycles to resume and help bones get stronger.

Full description

Low levels of estrogen found in physically active, premenopausal women with irregular or absent menstrual periods is likely caused by insufficient energy (calorie) intake compared to energy expenditure. Premenopausal women with menstrual disturbances and amenorrhea suffer from reductions in bone mineral density, particularly in the lumbar spine. Bone loss observed in amenorrheic women may be serious enough to result in osteoporotic fractures, but is also associated with a high prevalence of stress fractures. Increased calorie intake should help improve energy status, menstrual status, and bone health.

Comparison: Premenopausal women with irregular or absent menstrual periods will be assigned to either receive additional calories or serve as controls. A group of premenopausal women with normal menstrual periods will also be used for comparison.

Enrollment: 233 patients

Sex: Female

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria for Ovulatory Control Volunteers:

• 18-35 years
• BMI 16-25 kg/m2
• At least 2 hr/wk of aerobic exercise
• Gynecological age >/= 5 years
• Weight stable (+/- 2 kg) last 6 months
• History of regular menses for 6 months

Inclusion Criteria for Women with Irregular or Absent Menses:

• 18-35 years
• BMI 16-25 kg/m2
• At least 3 hr/wk of aerobic exercise
• Gynecological age >/= 5 years
• Weight stable (+/- 2 kg) last 6 months
• No menses within past 3 months or 6 or less menses in last 12 months
• Low to normal bone mass (L1-L4 Z score </=0)

Exclusion Criteria for all participants:

• Hormonal contraceptives in last 6 months
• Smoking currently
• Current clinical diagnosis of an eating disorder
• Use of medications incompatible with measurement of reproductive or metabolic hormones, including thyroid medications that may interfere with any of the study outcomes.
• Dietary habits incompatible with prescribed diet for study
• Any metabolic, reproductive or bone disease
• Sedentary individuals with less than 120 minutes (2 hrs) of activity per week

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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233 participants in 3 patient groups

EAMD+Calories

Experimental group

Description:

This group contains women with exercise-associated menstrual disturbances (EAMD) and receives an intervention of increased caloric intake during the 12-month intervention. The targeted increase in caloric intake is 20-30% of baseline energy expenditure.

Treatment:

Behavioral: EAMD+Calories

EAMD Control

No Intervention group

Description:

This group contains women with exercise-associated menstrual disturbances (EAMD) and undergoes the same procedures as the EAMD+Calories group. However, this group is instructed to maintain exercise and eating habits.

Heathy Control

No Intervention group

Description:

This group contains exercising women with regular, ovulatory menstrual cycles. this group is instructed to maintain body weight and exercise and eating habits.