This randomised trial will investigate the effect of calcium supplementation on bone and calcium metabolism in women during acute load carriage exercise. This study will test the hypothesis that calcium supplementation before load carriage exercise will attenuate the decline in serum ionised calcium and increase in parathyroid hormone and bone resorption.
Endurance exercise decreases serum ionised calcium and increases parathyroid hormone and bone resorption. These disturbances to calcium homeostasis can be attenuated by calcium supplementation before exercise. Military field exercises are characterised by high exercising energy expenditures, restricted dietary intake, and prolonged periods of load carriage. These exercise and nutritional challenges can result in impaired bone turnover, a negative calcium balance, and an increased risk of stress fracture. It is unknown if military load carriage disturbs calcium homeostasis and whether calcium supplementation before exercise can attenuate this disturbance. This crossover randomised controlled trial will investigate the effect of acute calcium supplementation on bone and calcium metabolism in women during acute load carriage exercise. Each participant will complete two 2 h load carriage trials. The trials will be performed after either consuming 1000 mg of calcium one hour before or with no treatment. During each experimental trial blood and urine will be sampled for markers of bone and calcium metabolism.
Primary Outcome: The absolute change in urine calcium balance (Ca44:Ca42) between pre- and post-load carriage will be compared between the non-supplemented (Control) and calcium supplemented trial (Supplement) using one-way ANCOVAs with pre-load carriage calcium balance (either as a ratio, or both the numerator and denominator) as the covariate, or a linear mixed model with the restricted maximum likelihood estimation to allow incorporation of incomplete data.
Secondary Outcomes: Circulating measures of bone turnover and calcium metabolism during load carriage will be compared between Control and Supplement using linear mixed models with the restricted maximum likelihood estimation to allow incorporation of incomplete data.
Condition | Calcium Deficiency |
---|---|
Treatment | calcium, Low energy availability |
Clinical Study Identifier | NCT04823156 |
Sponsor | Army Health Branch, British Army |
Last Modified on | 11 May 2022 |
,
You have contacted , on
Your message has been sent to the study team at ,
You are contacting
Primary Contact
Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.
Learn moreIf you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.
Learn moreComplete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.
Learn moreEvery year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.
Sign up as volunteer
Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!
No annotations made yet
Congrats! You have your own personal workspace now.