Breastfeeding and Exercise for Healthy Infants and Postpartum Moms Too!
Breastfeeding and Exercise for Healthy Infants and Postpartum Moms Too!
Approximately 8 million American women suffer from osteoporosis, and one out of every two
 women over the age of 50 will have an osteoporotic-related fracture in their lifetime (42).
 While epidemiological studies suggest that pregnancy and lactation are not associated with
 risk of fractures later in life, these studies did not control for site-specific decrements
 in bone mineral density (BMD). In addition, 55% of American women between the ages of 20 to
 39 are overweight (14). Excess weight retention after pregnancy increases a woman's risk for
 developing a chronic disease later in life (44). There is a paucity of research on exercise
 and dietary interventions in postpartum lactating women aimed at promotion of bone health and
 weight loss.

 The goal of this study is to promote long-term lifestyle changes through a home based
 strength training, aerobic, and nutrition intervention targeting overweight lactating women.
 The objective is to attenuate lactation-induced bone loss and promote weight loss. We
 hypothesize that the intervention group will lose a greater amount of fat mass while
 preserving lean mass and bone mineral mass and increase levels of anabolic hormones through
 diet and exercise compared to the minimal care group. Additionally, the acquisition of such
 knowledge is unique since no other studies have measured growth hormone and insulin-like
 growth factor-1 in lactating women with respect to bone and exercise. This intervention will
 encourage breastfeeding, weight loss and an increase in bone density resulting in healthy
 infants and mothers.

 The proposed research is the first to examine the effects of a resistance exercise and weight
 loss intervention on attenuation of lactation-induced bone loss in overweight women. To our
 knowledge, this is the first study to use MyPyramid for Menu Planner for Moms for dietary
 counseling using the total diet approach. The expected outcomes are the intervention group
 will lose weight while preserving lean body mass, bone mineral mass and increase
 cardiovascular fitness and strength compared to the minimal care group. Additionally, the
 exercise group will improve the overall quality of their diet using internet based
 technology. An increase in activity and promotion of weight loss through a modest reduction
 in calories may lead to overall improvement of the mother's bone and health status later in
 life.
Participants will be randomized, stratified by parity, into either an intervention or minimal
 care group after all baseline measurements are complete (3 +/- 1 wk postpartum).

 The specific aims of this project are to evaluate in overweight lactating women at 3 and 20
 weeks postpartum (PP) whether an exercise and weight loss intervention, compared to a minimal
 care group, will:

 1. Improve body composition. The working hypothesis for this aim is the intervention group
 will lose less lean body mass and bone mineral mass and promote more fat loss compared
 to the minimal care group at 20 weeks PP.

 2. Promote an increase in cardiovascular fitness and strength. The working hypothesis for
 this aim is the intervention group will increase predicted maximal oxygen consumption
 and maximal strength compared to the minimal care group at 20 weeks PP.

 3. Affect bone-related hormones. The working hypothesis for this aim is the intervention
 group will increase growth hormone and insulin-like growth factor-1 compared to the
 minimal care group at 20 weeks PP.

 4. Improve total diet or overall pattern of food eaten. The working hypothesis for this
 aim, based on menu modeling with MyPyramid (16), is the intervention group will improve
 the quality of their intake by consuming the recommended amounts of food groups
 established by MyPyramid compared to the minimal care group at 20 weeks PP.
Inclusion Criteria:

 -  To be eligible for the study, women must be less than 3 weeks postpartum, between the
 ages of 25 to 40, with a body mass index (BMI) between 25 and 30 kgm-2), exclusively
 breastfeeding, sedentary for the past 3 months (< 3 weekly sessions of moderate
 aerobic activity), non-smokers, medically cleared for exercise by their physician, and
 agree to randomization.

 Exclusion Criteria:

 -  Exclusion criteria for the study are delivery by cesarean section, have medical
 complications where exercise is contraindicated, or a disease that would affect
 hormone levels.