Breastfeeding mothers do a lot for their babies, but the process of breastfeeding can shortchange moms when it comes to bone mineral density.
During pregnancy and lactation a woman's body can show bone mineral loss even greater than what the average woman experiences after menopause. While bone mineral density usually returns to normal levels when lactation stops, it doesn't return to pre-pregnancy levels in all women.
But exercise, according to a new study, may help shore up that bone loss. Researchers from the University of North Carolina at Greensboro recruited 20 breastfeeding women, randomly assigning half to an exercise intervention group, and half to a control group that did no exercise. Neither group changed their diet.
The 16-week exercise program consisted of aerobic activity three days a week (brisk walking) and resistance training three days a week that emphasized increasing core strength. Individual exercises included squats, bench presses, push-ups, abdominal planks and dead lifts and were done at home with handheld weights and a stability ball. Since all study participants were sedentary at the beginning of the study, time and intensity of the exercises increased gradually.
All that exercise paid off--the workout group showed significantly less bone mineral density losses in the lumbar spine compared with the control group. The intervention group also showed greater muscular strength and improved endurance over the control group. That group also lost substantially less lean body mass than the control.
The study concluded: "Additional research is needed to determine whether these beneficial effects of exercise continue after weaning, resulting in higher [bone mineral density] and decreasing the risk of osteoporosis in later life."
The study appears in the October issue of the journal Medicine & Science in Sports & Exercise.
-- Jeannine Stein
Photo credit: Barbara Peacock/CORBIS