The Effects of Calcium and Glutamine Co-supplementation on Body Composition and Bone Mineral Density in Young Female Athletes: A Randomized Clinical Trial

Abstract

Background: Female athletes who experience menstrual disorders have an energy imbalance due to dietary restrictions and training. A significant problem arising from the daily training of such athletes is the imbalance between energy intake and energy expenditure, leading to fractures due to osteoporosis, amenorrhea, diabetes, and cardiovascular disease. The purpose of this study was to investigate and compare the complementary effect of calcium (Ca), Glutamine (Gln), and Ca+Gln supplements on bone mineral density (BMD), body composition, and physiological and biochemical symptoms of young female athletes with menstrual disorders during 90 days of the training program. Methods: In this randomized clinical trial (RCT), participants were classified into four groups: Ca supplementation group (Ca), Gln supplementation group (Gln), Ca+Gln supplementation group, and placebo group. Ca supplement containing 500 mg elemental Ca was given to the recipient groups daily. Gln supplement was given at the dose of 10,000 mg. The control group received maltodextrin (similar to Gln powder) as a placebo. BMD, serum Ca and vitamin D3, mid-arm upper circumference (MUAC), weight, and body mass index (BMI) were recorded in the four groups pre and post intervention. Results: Our study found that BMD differences in the three intervention groups were significant (P < 0.05). Results showed that Ca+Gln and Ca supplementation significantly improved BMD. This effect was observed in the Gln supplementation group too; however, it was lower than that of the Ca and Ca+Gln groups. Serum Ca was significantly elevated in the Ca group (P < 0.05). Conclusions: Ca+Glu supplement improves BMD in female athletes.