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Richard D. Lewis and Christopher M. Modlesky

Calcium and vitamin D can significantly impact bone mineral and fracture risk in women. Unfortunately, calcium intakes in women are low and many elderly have poor vitamin D status. Supplementation with calcium (~1000 mg) can reduce bone loss in premenopausal and late postmenopausal women, especially at sites that have a high cortical bone composition. Vitamin D supplementation slows bone loss and reduces fracture rates in late postmenopausal women. While an excess of nutrients such as sodium and protein potentially affect bone mineral through increased calcium excretion, phytoestrogens in soy foods may attenuate bone loss ihrough eslrogenlike activity. Weight-bearing physical activity may reduce the risk of osteoporosis in women by augmenting bone mineral during the early aduli years and reducing the loss of bone following menopause. High-load activities, such as resistance training, appear to provide the best stimulus for enhancing bone mineral; however, repetitive activities, such as walking, may have a positive impact on bone mineral when performed at higher intensities. Irrespective of changes in bone mineral, physical activities that improve muscular strength, endurance, and balance may reduce fracture risk by reducing the risk of falling. The combined effect of physical activity and calcium supplementation on bone mineral needs further investigation.

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Pamela J. Magee, L. Kirsty Pourshahidi, Julie M. W. Wallace, John Cleary, Joe Conway, Edward Harney, and Sharon M. Madigan

Background:

A high prevalence of vitamin D insufficiency/deficiency, which may impact on health and training ability, is evident among athletes worldwide. This observational study investigated the vitamin D status of elite Irish athletes and determined the effect of wintertime supplementation on status.

Methods:

Serum 25-hydroxyvitamin D [25(OH)D], calcium, and plasma parathyroid hormone were analyzed in elite athletes in November 2010 (17 boxers, 33 paralympians) or March 2011 (34 Gaelic Athletic Association [GAA] players). A subset of boxers and paralympians (n = 27) were supplemented during the winter months with either 5,000 IU vitamin D3/d for 10–12 weeks or 50,000 IU on one or two occasions. Biochemical analysis was repeated following supplementation.

Results:

Median 25(OH)D of all athletes at baseline was 48.4 nmol/L. Vitamin D insufficiency/deficiency (serum 25(OH)D <50 nmol/L) was particularly evident among GAA players (94%) due to month of sampling. Wintertime supplementation (all doses) significantly increased 25(OH)D (median 62.8 nmol/L at baseline vs. 71.1 nmol/L in April or May; p = .001) and corrected any insufficiencies/deficiencies in this subset of athletes. In contrast, 25(OH)D significantly decreased in those that did not receive a vitamin D supplement, with 74% of athletes classed as vitamin D insufficient/deficient after winter, compared with only 35% at baseline.

Conclusions:

This study has highlighted a high prevalence of vitamin D insufficiency/deficiency among elite Irish athletes and demonstrated that wintertime vitamin D3 supplementation is an appropriate regimen to ensure vitamin D sufficiency in athletes during winter and early spring.

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Amanda Zaleski, Beth Taylor, Braden Armstrong, Michael Puglisi, Priscilla Clarkson, Stuart Chipkin, Charles Michael White, Paul D. Thompson, and Linda S. Pescatello

)D groups. Multivariable regression analyses were used to test the influence of baseline 25(OH)D on resting SBP, DBP, peak SBP, and absolute peak SBP change while controlling for potential covariates such as age, sex, BMI, medication use, vitamin D supplementation use, and season. Chi-squared test examined

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Blair Crewther, Christian Cook, John Fitzgerald, Michal Starczewski, Michal Gorski, and Joanna Orysiak

between 25(OH)D concentrations and muscular (eg, strength, power, and work) and aerobic fitness ( 4 , 18 , 19 , 25 ), performance differences between subgroups that differ in 25(OH)D status ( 22 ), and performance gains following vitamin D supplementation ( 24 , 39 ). Other cross-sectional studies

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Eric S. Rawson, Mary P. Miles, and D. Enette Larson-Meyer

/d; identify deficiencies through blood work, consult with a physician and sport nutritionist, and take corrective actions in insufficient/ deficient athletes with changes in lifestyle, food intake, and possibly supplementation; indiscriminate vitamin D supplementation for athletes is not advised; compensatory

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run. Conclusion.— Contrary to our hypothesis, two weeks vitamin D supplementation (10.000 UI /day), did not change the postexercise hepcidin response in long-distance runners. Impact of Vitamin D Supplementation on Hormone Levels and Cytokine Generation During Ultramarathon Katarzyna Kasprowicz, PhD

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Hanan A. Alfawaz, Soundararajan Krishnaswamy, Latifah Al-Faifi, Halima Ali Bin Atta, Mohammad Al-Shayaa, Saad A. Alghanim, and Nasser M. Al-Daghri

for protection from cardiovascular diseases ( Nunez-Cordoba & Martinez-Gonzalez, 2011 ), calcium and vitamin D supplementation for increasing bone mineral density ( Silk et al., 2015 ), and vitamin C in preventing and treating the common cold ( Hemila & Chalker, 2013 ). Despite the absence of

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Katie Crockett, Saija A. Kontulainen, Jonathan P. Farthing, Philip D. Chilibeck, Brenna Bath, Adam D.G. Baxter-Jones, and Catherine M. Arnold

version 22.0 (IBM SPSS Statistics for Macintosh, Version 22.0. Armonk, NY: IBM Corp). Significance was set at α = .05. Results There were no significant differences in age, height, weight, PASE scores, number of medications, age of onset of menopause, or total calcium or vitamin D supplementation between

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Francisco Alvarez-Barbosa, Jesús del Pozo-Cruz, Borja del Pozo-Cruz, Antonio García-Hermoso, and Rosa María Alfonso-Rosa

vitamin D supplementation Note . WBV = whole-body vibration; A = whole-body vibration accelerations; C = control; F = frequency; P = peak-to-peak displacement amplitude; TUG = Timed up and Go test; EQ-5D = Euroqol-5 dimension; PS = physical therapy; PPA = physiological profile assessment; KE = knee

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Megan A. Kuikman, Margo Mountjoy, Trent Stellingwerff, and Jamie F. Burr

with those who consumed 1,500 mg of calcium per day ( Nieves et al., 2010 ). Furthermore, in the armed services, female recruits who received a 2,000 mg calcium and 800 IU vitamin D supplement had a 21% lower rate of stress fracture than those receiving a placebo over 8 weeks of training ( Lappe et