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Research examining the preventative effects of calcium and vitamin D supplementation has focused on children and females, leaving the effects on male bone mineral density (BMD) largely unexplored. Thus, the aim of this systematic review and meta-analysis is to examine the efficacy of calcium supplementation, with or without vitamin D for improving BMD in healthy males. Medline, EMBASE, SPORTDiscus, Academic Search Complete, CINHAHL Plus and PubMed databases were searched for studies including healthy males which provided participants calcium supplementation with or without vitamin D and used changes to BMD as the primary outcome measure. Between trial standardized mean differences of percentage change from baseline in BMD of femoral neck, lumbar spine, total body and total hip sites were calculated. Nine studies were included in the systematic review with six references totaling 867 participants contributing to the meta-analysis. Significant pooled effects size (ES) for comparison between supplementation and control groups were found at all sites included in the meta-analysis. The largest effect was found in total body (ES = 0.644; 95% CI = 0.406–0.883; p < .001), followed by total hip (ES = 0.483, 95% CI= 0.255–0.711, p < .001), femoral neck (ES = 0.402, 95% CI = 0.233–0.570, p = .000) and lumbar spine (ES = 0.306, 95% CI = 0.173–0.440, p < .001). Limited evidence appears to support the use of calcium and vitamin D supplementation for improving BMD in older males. There is a need for high quality randomized controlled trials, especially in younger and middle-aged male cohorts and athletic populations to determine whether supplementation provides a preventative benefit.

The purpose of this study was to measure the influence of diet, exercise, or both on body composition and cardiorespiratory fitness in obese women. Ninety-one obese subjects were randomized into one of four groups: diet (D) (4.19–5.44 MJ or 1,200–1,300 kcal/day), exercise (E) (five 45-min sessions at 78.5 ± 0.5% maximum heart rate), exercise and diet (ED), and controls (C). Maximal aerobic power and body composition were measured in all subjects before and after a 12-week diet intervention period. Subjects in D and ED lost 7.8 ± 0.7 and 8.1 ± 0.6 kg body mass, with no significant change for E relative to C. Losses of percent body fat and fat mass were significantly greater in D and ED but not in E relative to C. The change in VO₂max was greater in ED and E but not D when compared to C. Results indicate that moderate aerobic exercise training during a 12-week period has no discernible effects on body composition but does improve cardiorespiratory fitness in dieting obese women.

Ovariectomy leads to weight gain primarily in the form of adipose tissue in rodents. The authors investigated whether swimming improves ovariectomy-induced obesity through activation of peroxisome proliferatoractivated receptor α (PPARα) in the skeletal muscle of female ovariectomized (OVX) mice, an animal model of postmenopausal women. Female mice were randomly divided into 3 groups (n = 8/group): a sedentary sham-operated group, a sedentary OVX group, and a swim-trained OVX group. After mice were subjected to swim training or kept sedentary for 6 wk, the authors studied the effects of swimming on not only bodyweight gain, white adipose tissue (WAT) mass, adipocyte size, and skeletal-muscle lipid accumulation but also the expression of skeletal-muscle PPARα target genes. Sedentary OVX mice had significantly higher body weight and WAT than sedentary sham mice. However, swim training reduced body-weight gain, WAT mass, and adipocyte size of OVX mice. Swim-trained OVX mice had significantly lower levels of serum triglycerides and total cholesterol than sedentary OVX mice. Lipid accumulation in skeletal muscle was also markedly decreased by swimming. Concomitantly, swim training significantly increased mRNA levels of skeletal-muscle PPARα and its target enzymes, as well as uncoupling protein 3 (UCP3) responsible for fattyacid oxidation. These results suggest that swimming can effectively prevent weight gain, adiposity, adipocyte hypertrophy, and lipid disorders caused by ovariectomy, in part through the activation of PPARα and UCP3, in the skeletal muscle of female mice and may contribute to the alleviation of metabolic syndrome, including obesity, hyperlipidemia, and Type 2 diabetes in postmenopausal women.

The authors studied the effects of antioxidant diet supplementation with an almond-based beverage on neutrophil antioxidants, nitrite, and protein oxidative alterations after exercise. Fourteen trained male amateur runners were randomly assigned in a double-blind fashion to receive antioxidant supplementation (152 mg/d vitamin C and 50 mg/d vitamin E) or placebo using an almond-based beverage for 1 mo and participated in a half-marathon race. Blood samples were taken before and after the half-marathon and after 3 hr recovery. Supplementation significantly increased basal neutrophil vitamin C compared with placebo (p < .05). Exercise increased neutrophil vitamin E levels in the supplemented group and decreased vitamin C in both groups after recovery (p < .05). Neutrophil catalase and glutathione peroxidase gene expression and nitrite levels were significantly increased as result of exercise (p < .05). Nitrotyrosine and protein carbonyl derivates increased only in the placebo group after exercise (p < .05), and these values remained high at recovery. No significant differences were evidenced in caspase-3 activity and DNA damage. Antioxidant supplementation with vitamins C and E reduced the exercise-induced oxidation of proteins in neutrophils, without altering the antioxidant adaptive response, as evidenced by the increased catalase and glutathione peroxidase gene expression.

Low energy availability (LEA) describes the disruption in normal physiological function existent when insufficient energy intake is combined with exercise. To conserve energy a range of endocrine adaptations occur, impairing health and athletic performance. The prevalence of LEA has not been fully established especially among recreational exercisers. Determining recreational exercisers at risk of LEA may help to maximize prevention, early diagnosis and treatment. The design of this study was a cross-sectional online survey. One-hundred and nine female recreational exercisers, with a mean age of 23.8 (SD 6.9) years were recruited via gyms and fitness centers throughout NZ. Participants completed an online questionnaire including questions from the LEAF-Q (Low Energy Availability in Females Questionnaire). A total of 45.0% (CI, 35.4%, 54.8%) of participants were classified as “at risk“ of LEA. For every extra hour of exercise per week the odds of being at risk of LEA were 1.13 times greater (CI 1.02, 1.25, p = .016). All participants reporting previous stress fracture injuries (n = 4) were classified as at risk for LEA. Significantly more subjects participating in an individual sport were classified as at risk for LEA (69.6%, CI 24.3%, 54.8%) compared with team sports (34.8%, CI 18.7%, 40.5%) (p = .006). The high prevalence of female recreational exercisers at risk of LEA is of concern, emphasizing the importance of increasing awareness of the issue, and promoting prevention and early detection strategies, so treatment can be implemented before health is severely compromised.

Ginseng is one of the most popular herbal supplements in the world. Although it is used for the treatment and prevention of many ailments, it is also used to increase work efficiency and is purported to increase energy and physical stamina. Athletes use ginseng for its alleged performance-enhancing attributes. However, many studies examining the pharmacological effects of ginseng on physical performance have not employed sound scientific design and methodology. The purpose of this review is to provide an update on published empirical research focusing primarily on the efficacy of ginseng with respect to physical and athletic performance. Despite attempts in recent investigations to improve on the scientific rigor used in examining the ergogenic properties of ginseng, the authors conclude that many of the same methodological shortcomings observed in earlier studies persist. Enhanced physical performance after ginseng administration in well-designed investigations remains to be demonstrated.

In this review, we outline key principles for prevention of injury and illness in aquatic sports, detail the epidemiology of injury and illness in aquatic athletes at major international competitions and in training, and examine the relevant scientific evidence on nutrients for reducing the risk of illness and injury. Aquatic athletes are encouraged to consume a well-planned diet with sufficient calories, macronutrients (particularly carbohydrate and protein), and micronutrients (particularly iron, zinc, and vitamins A, D, E, B6, and B12) to maintain health and performance. Ingesting carbohydrate via sports drinks, gels, or sports foods during prolonged training sessions is beneficial in maintaining energy availability. Studies of foods or supplements containing plant polyphenols and selected strains of probiotic species are promising, but further research is required. In terms of injury, intake of vitamin D, protein, and total caloric intake, in combination with treatment and resistance training, promotes recovery back to full health and training.

The aim of the study was to evaluate the effectiveness of an intervention program that combined nutrition education and prevention of disordered eating in a group of female professional dance students. Thirty-two dancers, aged 19-25 years, took part in the program. Evaluation was done by a series of questionnaires that participants were asked to complete on 3 occasions. Assessments of body composition and dietary intake were also performed. Significant improvements in nutrition knowledge as well as a decrease in abnormal eating behavior and dietary restraint were observed at post intervention. At 6-month follow-up, the positive effects were maintained and further benefits were recorded; only nutrition knowledge showed a minor decline. Participants who were at higher risk for adopting abnormal eating behavior benefited the most from the program. These findings encourage the implementation of intervention programs in groups of young women that experience particular pressures for controlling body weight.