The Preventive Effect of Calcium Supplementation on Weak Bones Caused by the Interaction of Exercise and Food Restriction in Young Female Rats During the Period from Acquiring Bone Mass to Maintaining Bone Mass.
Increasing calcium (Ca) intake is important for female athletes with a risk of weak bone caused by inadequate food intake. The aim of the present study was to examine the preventive effect of Ca supplementation on low bone strength in young female athletes with inadequate food intake, using the rats as an experimental model. Seven-week-old female Sprague-Dawley rats were divided into four groups: the sedentary and ad libitum feeding group (SED), voluntary running exercise and ad libitum feeding group (EX), voluntary running exercise and 30% food restriction group (EX-FR), and a voluntary running exercise, 30% food-restricted and high-Ca diet group (EX-FR+Ca). To Ca supplementation, we used 1.2% Ca diet as "high-Ca diet" that contains two-fold Ca of normal Ca diet. The experiment lasted for 12 weeks. As a result, the energy availability, internal organ weight, bone strength, bone mineral density, and Ca absorption in the EX-FR group were significantly lower than those in the EX group. The bone strength and Ca absorption in the EX-FR+Ca group were significantly higher than those in the EX-FR group. However, the bone strength in the EX-FR+Ca group did not reach that in the EX group. These results suggested that Ca supplementation had a positive effect on bone strength, but the effect was not sufficient to prevent lower bone strength caused by food restriction in young female athletes.
Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Yuki
Y
Aikawa
Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Umon
U
Agata
Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Yuya
Y
Kakutani
Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Shoyo
S
Kato
Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Yuichi
Y
Noma
Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Satoshi
S
Hattori
Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
Hitomi
H
Ogata
Department of food and nutrition, Japan Women's University, 2-8-1 Mejirodai, Bunkyo-Ku, Tokyo, 112-8681, Japan.
Ikuko
I
Ezawa
Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan. ominaomi@taiiku.tsukuba.ac.jp.|Institute of Health and Sports Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8574, Japan. ominaomi@taiiku.tsukuba.ac.jp.
Naomi
N
Omi
D000818:Animals; D015519:Bone Density / Q000187:drug effects; D001846:Bone Development / Q000187:drug effects*; D001851:Bone Diseases, Metabolic / Q000178:diet therapy / Q000517:prevention & control*; D016723:Bone Remodeling / Q000187:drug effects; D001842:Bone and Bones / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000187:drug effects*; D002136:Calcium, Dietary / Q000494:pharmacology*; D031204:Caloric Restriction / Q000009:adverse effects*; D019587:Dietary Supplements; D005260:Female; D005508:Food Deprivation / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000009:adverse effects*; D011859:Radiography; D051381:Rats; D017207:Rats, Sprague-Dawley; D012420:Running / Q000502:physiology
D002136:Calcium, Dietary
Bone strength; Growing rat; High-Ca diet; Inadequate food intake; Young female athlete