The purpose of this study was to test the effect of acute dairy calcium intake on exercise energy metabolism and endurance performance. Trained female runners completed two trials. Each trial consisted of a 90-min glycogen depletion run followed by a self-paced 10K time trial, conducted one hour after consumption of a high dairy (500 mg Ca+2) or low dairy (80 mg Ca+2) meal. During the 90-min run, blood samples and respiratory gases were collected. No treatment main effects of acute dairy intake were found for respiratory exchange ratio (RER), calculated fat oxidation, lactate, glycerol, or 10K time. Following this protocol, acute dairy calcium intake did not alter fat utilization or endurance performance in trained female runners.
Kimberly M. White, Roseann M. Lyle, Michael G. Flynn, Dorothy Teegarden and Shawn S. Donkin
Rebekah D. Alcock, Gregory C. Shaw, Nicolin Tee, Marijke Welvaert and Louise M. Burke
12–24 hr after the consumption of a habitual breakfast (BL1 and BL2) or 20 g of either collagen-containing (gelatin and hydrolyzed collagen) or dairy (calcium caseinate and hydrolyzed casein) supplements. Line shows median, boxes represent 25th–75th percentiles, and whiskers show maximum and minimum
Deborah Leachman Slawson, Barbara S. McClanahan, Linda H. Clemens, Kenneth D. Ward, Robert C. Klesges, Christopher M. Vukadinovich and Edwin D. Cantler
Adequate calcium intake is integral to bone health as well as for optimal athletic performance. This study was conducted to investigate: (a) food sources of calcium in a sample of collegiate athletes, (b) gender and/or ethnic differences in food sources of calcium, and (c) whether athletes that derive less of their calcium intake from dairy sources increase their calcium intake from supplements or other food sources. Participants were African-American and Euro-American NCAA Division 1-A athletes. Eighty-five men and 59 women participated. Calcium intake for the previous 7-day period was assessed with a brief calcium screen.
Men consumed significantly more calcium than women (1,354 vs. 898 mg/day), with female cross-country runners exhibiting the lowest average intake (605 mg/day). Both men and women obtained the majority of their calcium from dairy products and mixed dishes, while men consumed significantly more calcium-fortified foods. Several gender and ethnic interactions for calcium intake from food groups were found. Mean total dairy calcium intake was found to vary according to total calcium intake in men, and supplemental calcium was not used to augment low dairy intakes of calcium in any group.
While African-Americans and Euro-Americans athletes were consuming similar levels of calcium, the female athletes in the sample did not get adequate amounts.