; Waldron-Lynch et al., 2010 ; Warrington et al., 2009 ) have consistently reported that male flat jockeys present with low bone mineral density (BMD), with Z -scores often lower than –1. Such low bone densities are often considered to be due to a combination of nutritional factors, including low energy
George Wilson, Dan Martin, James P. Morton and Graeme L. Close
Kerri M. Winters-Stone and Christine M. Snow
We conducted a double-blind, placebo-controlled, randomized trial to determine whether 1 year of supplemental calcium intake would augment hip [greater trochanter, GT, femoral neck (FN), total hip (TH)], spine (LS), and femoral mid-shaft (Fmr) BMD in female distance runners. Twenty-three women (age: 23.7 ± 4.7 yrs, height: 165.6 ± 6.3 cm, weight: 55.7 ± 6.1 kg) were randomly assigned to receive either 1000 mg/d of supplemental calcium (N = 13) or placebo tablets (N = 10) for 1 year. BMD was determined by DXA (Hologic 1000-W) and tablet compliance by self-report logs. Compliance averaged 79% and 71% for supplement and placebo groups, respectively. Calcium supplementation did not affect hip or spine BMD, but did prevent loss at the femoral mid-shaft (GT: –0.5% vs. 0.2%, FN: 0.9% vs. 1.1%, TH: –0.3% vs. 0.2%, LS: 0.3% vs. 1.2%, Fmr: 0.1% vs. –1.8%, for calcium vs. placebo, respectively). We conclude that the addition of 800 mg/d of supplemental calcium to the diet of young adult female distance runners with habitual calcium intakes of ~1000 mg/d, prevents cortical but not trabecular bone loss.
Jennifer Sygo, Alexandra M. Coates, Erik Sesbreno, Margo L. Mountjoy and Jamie F. Burr
, and leptin, and can lead to an increase in cortisol and ghrelin ( Hulmi et al., 2017 ; Loucks, 2007 ; Loucks & Thuma, 2003 ; Thong et al., 2000 ). Low energy availability contributes to reduced bone density and an increased risk of stress fracture and osteoporosis ( Keen & Drinkwater, 1997
Alba Gómez-Cabello, Germán Vicente-Rodríguez, Isabel Navarro-Vera, Diana Martinez-Redondo, Carmen Díez-Sánchez and José Antonio Casajús
The aim of this study was to provide information about the relationship of bone mineral content (BMC) and density (BMD) with some physical-fitness-related variables in a sample of women with fibromyalgia (FM) and age-matched women without FM. Twenty-eight women clinically diagnosed with FM (age 51.1 ± 8.4 yr, M ± SD) and 22 age-matched controls participated in the study. Whole-body BMC and BMD, lean mass, handgrip strength, quadriceps strength, and cardiovascular fitness were measured in all participants. The association between physical-fitness variables and bone-related variables was tested by linear regression controlling for body weight as a possible confounder. There were no differences in BMC or BMD between groups. Women with FM had lower values of handgrip strength, quadriceps strength, and VO2peak than the control group. Handgrip strength and aerobic capacity were associated with BMC and BMD and quadriceps strength was associated with BMD in women with FM; however, only VO2peak was associated with BMC in the group of women without FM. Bone mass of women with FM may be more susceptible to changes in physical fitness than that of the women without fibromyalgia.
Athletes are influenced by coaches, other athletes, media, parents, the national sport governing body, members of the sports medicine team, and the athlete's own desire for success. It is impossible, therefore, for one member of the sports medicine team to unilaterally determine workable solutions that enhance performance and diminish health problems in an athlete. A focus on ensuring that the athlete can perform to the best of her ability is a key to encouraging discussion between the nutritionist, athlete, and coach. Using the assumption that health and top athletic performance are compatible, this focus on performance provides a discussion point that all parties can agree to and, if approached properly, also fulfills the nutritionist's goal of achieving optimal nutritional status. Membership on the sports medicine team mandates that the nutritionist know the paradigms and health risks associated with the sport and develop assessment and feedback procedures specific to the athlete's needs.
Synchronized swimming enjoys worldwide popularity and has been part of the formal Olympic program since 1984. Despite this, relatively little research has been conducted on participant nutrition practices and requirements, and there are significant gaps in the knowledge base despite the numerous areas in which nutrition could affect performance and safety. This review aimed to summarize current findings and identify areas requiring further research. Uniform physique in team or duet events may be more important than absolute values for muscularity or body fat, but a lean and athletic appearance remains key. Synchronized swimmers appear to have an increased risk of developing eating disorders, and there is evidence of delayed menarche, menstrual dysfunction, and lower bone density relative to population norms. Dietary practices remain relatively unknown, but micronutrient status for iron and magnesium may be compromised. More research is required across all aspects of nutrition status, anthropometry, and physiology, and both sports nutrition and sports medicine support may be required to reduce risks for participants.
Joseph M. Kindler, Hannah L. Ross, Emma M. Laing, Christopher M. Modlesky, Norman K. Pollock, Clifton A. Baile and Richard D. Lewis
Assessment of physical activity in clinical bone studies is essential. Two bone-specific physical activity scoring methods, the Bone Loading History Questionnaire (BLHQ) and Bone-Specific Physical Activity Questionnaire (BPAQ), have shown correlations with bone density and geometry, but not architecture. The purpose of this study was to determine relationships between physical activity scoring methods and bone architecture in non-Hispanic white adolescent females (N = 24; 18-19 years of age). Bone loading scores (BLHQ [hip and spine] and past BPAQ) and energy expenditure (7-day physical activity recall) were determined from respective questionnaires. Estimates of trabecular and cortical bone architecture at the nondominant radius and tibia were assessed via magnetic resonance imaging. Total body and regional areal bone mineral density (aBMD), as well as total body fat mass and fat-free soft tissue (FFST) mass were assessed via dual energy X-ray absorptiometry. Pearson’s correlations and partial correlations adjusting for height, total body fat mass, and FFST were performed. Hip BLHQ scores were correlated with midtibia cortical volume (r = .43; p = .03). Adjusted hip and spine BLHQ scores were correlated with all midtibia cortical measures (r = .50-0.58; p < .05) and distal radius apparent trabecular number (r = .46-0.53; p < .05). BPAQ scores were correlated with all midtibia cortical (r = .41-0.51; p < .05) and most aBMD (r = .47-0.53; p < .05) measures. Energy expenditure was inversely associated with femoral neck aBMD only after statistical adjustment (r = .49, p < .05). These data show that greater load-specific physical activity scores, but not energy expenditure, are indicative of greater midtibia cortical bone quality, thus supporting the utility of these instruments in musculoskeletal research.
John Petrizzo, Frederick J. DiMenna, Kimberly Martins, John Wygand and Robert M. Otto
To achieve the criterion appearance before competing in a physique competition, athletes undergo preparatory regimens involving high-volume intense resistance and aerobic exercise with hypocaloric energy intake. As the popularity of “drug-free” competition increases, more athletes are facing this challenge without the recuperative advantage provided by performance-enhancing drugs. Consequently, the likelihood of loss of lean body and/or bone mass is increased. The purpose of this investigation was to monitor changes in body composition for a 29-year-old self-proclaimed drug-free female figure competitor during a 32-week preparatory regimen comprising high-volume resistance and aerobic exercise with hypocaloric energy intake. We used dual-energy x-ray absorptiometry (DXA) to evaluate regional fat and bone mineral density. During the initial 22 weeks, the subject reduced energy intake and engaged in resistance (4–5 sessions/week) and aerobic (3 sessions/week) training. During the final 10 weeks, the subject increased exercise frequency to 6 (resistance) and 4 (aerobic) sessions/week while ingesting 1130–1380 kcal/day. During this 10-week period, she consumed a high quantity of protein (~55% of energy intake) and nutritional supplements. During the 32 weeks, body mass and fat mass decreased by 12% and 55%, respectively. Conversely, lean body mass increased by 1.5%, an amount that exceeded the coefficient of variation associated with DXA-derived measurement. Total bone mineral density was unchanged throughout. In summary, in preparation for a figure competition, a self-proclaimed drug-free female achieved the low body-fat percentage required for success in competition without losing lean mass or bone density by following a 32-week preparatory exercise and nutritional regimen.
Bernadette L. Foster, Jeff W. Walkley and Viviene A. Temple
The purpose of this study was to describe and compare the bone mineral density of women with intellectual disability (WID) and a comparison group (WOID) matched for age and sex. One hundred and five women, ages 21 to 39, M = 29, were tested for their bone mineral density levels at the lumbar spine and three sites of the proximal femur using dual energy X-ray absorptiometry. No significant difference between groups existed (λ = 0.94, F(4, 98) = 1.68, p = .16, η2 = .06); however, one-sample t tests revealed that bone mineral density for the WID group (n = 35) was significantly lower than zero at the Ward’s triangle (p < .01) and the lumbar spine (p < .05). Approximately one-quarter of WID had low bone density at these two sites, suggesting that WID may be at risk of osteoporotic fracture as they age.
Paula B. Costa, Scott R. Richmond, Charles R. Smith, Brad Currier, Richard A. Stecker, Brad T. Gieske, Kimi Kemp, Kyle E. Witherbee and Chad M. Kerksick
and concluded that strength, muscular endurance, and aerobic capacity were important attributes but did not have any measures of bone health, EI, or EA. To our knowledge, no literature exists on the bone density, body composition, resting metabolism, EA, and dietary intake of competitive, collegiate