Oral Calcium Loading Before Exercise Influences PTH and CTX Responses

Timing of calcium (Ca) ingestion relative to exercise may attenuate observed increases in parathyroid hormone (PTH) and c-terminal telopeptide of type I collagen (CTX, a marker of bone resorption). Controlled Ca supplementation studies have typically used doses of >1000 mg, but it is not known how much Ca is absorbed. PURPOSE: to quantify Ca absorption during exercise when preceded by a high (H: 1015 mg) or low (L: 215 mg) Ca-containing meal and...