The biomechanical changes due to increased arm mass in individuals with high body mass index (BMI) may lead to altered scapular motions at the shoulder joint. Scapula kinematic alterations are often associated with shoulder pain and pathology, and if present in overweight or obese individuals could impact shoulder health. The purpose of this study was to examine if scapula biomechanics differ between groups separated by BMI. Three-dimensional scapula kinematic data during arm elevation were collected on 41 subjects, and then compared between higher BMI (BMI ≥ 27; n = 10) and lower BMI (BMI ≤ 23; n = 10) individuals, both with and without holding a 1.36 kg (3 lb) weight. Data were analyzed with a mixed-model ANOVA with Group and Elevation Angle the between- and within-subject factors, respectively. The higher BMI group had significantly greater scapula upward rotation than the lower BMI group at 120° for both the unweighted and weighted tasks. Individuals with higher BMI in this study had altered scapulothoracic movement, which may be a strategy to better manage increased arm mass. With increased scapula upward rotation also reported in groups with rotator cuff tears, this study supports the potential link between high BMI, kinematics, and rotator cuff pathology.
Miti Gupta, Amitabh Dashottar and John D. Borstad
Martin D. Hoffman, Philip S. Clifford, Božo Bota, Michael Mandli and Gregory M. Jones
A theoretical analysis was used to evaluate the effect of body mass on the mechanical power cost of cross-country skiing and roller skiing on flat terrain. The relationships between body mass and the power cost of overcoming friction were found to be different between cross-country skiing on snow and roller skiing. Nevertheless, it was predicted that the heavier skier should have a lower oxygen cost per unit of body mass for roller skiing, as is the case for snow skiing. To determine whether the theoretical analysis was supported by experimental data, oxygen consumption measurements were performed during roller skiing by six male cross-country ski racers who spanned a 17.3-kg range in body mass. The theoretical analysis was supported by the experimental findings of decreases in oxygen consumption for each kg increase in body mass of approximately 1.0% for the double pole technique, 1.8% for the kick double pole technique, and 0.6% for the VI skate technique.
Martin Švehlík, Kryštof Slabý, Tomáš Trc̆ and Jir̆í Radvanský
The aim of the study is to investigate whether the net nondimensional oxygen utilization scheme is able to detect postoperative improvement in the energy cost of walking in children with cerebral palsy and to compare it with a body mass normalization scheme. We evaluated 10 children with spastic cerebral palsy before and 9 months after equinus deformity surgery. Participants walked at a given speed of 2 km/hr and 3 km/hr on a treadmill. Oxygen utilization was measured, and mass relative VO2 and net nondimensional VO2 were calculated. Coefficient of variation was used for the description of variability among subjects. Postoperatively, gait kinematics normalized and the mass relative VO2 and net nondimensional VO2 showed significant improvement. Net nondimensional VO2 is able to detect postoperative improvement with smaller variability among subjects than body mass related normalization in children with cerebral palsy.
Shivam Bhan, Iris Levine and Andrew C. Laing
The biomechanical effectiveness of safety floors has never been assessed during sideways falls with human volunteers. Furthermore, the influence of body mass index (BMI) and gender on the protective capacity of safety floors is unknown. The purpose of this study was to test whether safety floors provide greater impact attenuation compared with traditional flooring, and whether BMI and gender modify their impact attenuation properties. Thirty participants (7 men and 7 women of low BMI; 7 men and 9 women of high BMI) underwent lateral pelvis release trials on 2 common floors and 4 safety floors. As a group, the safety floors reduced peak force (by up to 11.7%), and increased the time to peak force (by up to 25.5%) compared with a traditional institutional grade floor. Force attenuation was significantly higher for the low BMI group, and for males. Force attenuation was greatest for the low BMI males, averaging 26.5% (SD = 3.0) across the safety floors. These findings demonstrate an overall protective effect of safety floors during lateral falls on the pelvis, but also suggest augmented benefits for frail older adults (often with low body mass) who are at an increased risk of hip fracture.
John T. Foley, Meghann Lloyd and Viviene A. Temple
This study examined temporal trends in body mass index (BMI) among United States adults with intellectual disability (ID) participating in Special Olympics from 2005 to 2010. In addition, the prevalence of obesity was compared with published National Health and Nutrition Examination Survey (NHANES) statistics. After data cleaning, 6,004 height and weight records (male = 57%) were available from the Special Olympics International Healthy Athletes Health Promotion database for the calculation of BMI. Rates of overweight and obesity were very high but generally stable over time. Compared with NHANES statistics, the prevalence of obesity was significantly higher for Special Olympics female participants in each data collection cycle. Integrated efforts to understand the social, environmental, behavioral, and biological determinants of obesity and among Special Olympics participants are needed.
Eva D’Hondt, Benedicte Deforche, Ilse De Bourdeaudhuij and Matthieu Lenoir
The purpose of this study was to investigate gross and fine motor skill in overweight and obese children compared with normal-weight peers. According to international cut-off points for Body Mass Index (BMI) from Cole et al. (2000), all 117 participants (5–10 year) were classified as being normal-weight, overweight, or obese. Level of motor skill was assessed using the Movement Assessment Battery for Children (MABC). Scores for balance (p < .01) and ball skills (p < .05) were significantly better in normal-weight and overweight children as compared with their obese counterparts. A similar trend was found for manual dexterity (p < .10). This study demonstrates that general motor skill level is lower in obese children than in normal-weight and overweight peers.
Justine J. Reel, Robert A. Bucciere and Sonya SooHoo
Individuals with intellectual disabilities are largely marginalized within society and are understudied as a group (Reel & Bucciere, 2011). Although there have been numerous body image studies with able-bodied athletes, this study represents the first attempt to explore body image of male and female Special Olympics athletes. Athletes (N = 103) were 18–61 years of age (M = 33.34; SD = 11.20) and represented mild to moderate severity for diagnosable intellectual disabilities. Height and weight were measured to determine body mass index (BMI). Body image was verbally assessed via individual interviews using the Figure Ratings Scale and open-ended items. Female athletes had a significantly higher BMI (M = 33.02, SD = 9.28) than male athletes (M = 28.24, SD = 7.38). The BMI means for the female and male athletes met the classifications for obese and overweight, respectively. There was also a negative relationship between body satisfaction and BMI in the overall sample (r = -.46), male athletes only (r = -.51), and female athletes only (r = -.38, indicating that higher BMI was associated with lower body satisfaction. Descriptive statistics revealed that 51% of female athletes and 37% of male athletes desired a thinner physique, whereas 20% of female athletes and 29.6% of male athletes wanted to be larger. There were no significant gender differences in levels of overall body dissatisfaction in this study.
Tina Smith, Sue Reeves, Lewis G. Halsey, Jörg Huber and Jin Luo
decrease in physical activity has been shown to have an inverse relationship with body mass. 3 , 4 Furthermore, obese people who undertake more physical activity have been shown to be metabolically healthier than their less active counterparts. 5 , 6 It is still unclear as to the effects of being
Ai-Wen Hwang, Chiao-Nan Chen, I-Chin Wu, Hsin-Yi Kathy Cheng and Chia-Ling Chen
This cross-sectional study investigated the correlates of body mass index (BMI) and risk factors for overweight among 91 children with motor delay (MD) aged 9–73 months. Anthropometric measurements and questionnaires regarding multiple risk factors were obtained. Simple correlations between BMI percentile classifications and potential predictors were examined using Spearman’s rank/Pearson’s correlations and χ2 analysis. Multiple predictors of overweight were analyzed using logistic regression. BMI was correlated positively with higher caloric intake (rs = .21, p < .05) and negatively with passive activity (rs = -.21, p < .05). When multiple predictors were considered, more severe dysphagia (odds ratio [OR], 2.81, p = .027, 95% confidence interval [CI], 1.13–7.04) and antiepileptic drug use (OR, 19.12, p = .008, 95% CI, 2.14–170.81) had significant partial effects on overweight status. Agencies supporting early development should consider caregiver education regarding the potential implication of feeding style and medication on BMI.
Dorota Sadowska, Rafał Stemplewski and Robert Szeklicki
The aim of this study was to assess the effect of physical exercise on postural stability in sighted participants and individuals who are visually impaired, adjusted for potential modulatory effects of physical activity level and body mass index (BMI). The study included 23 participants who were severely visually impaired and 23 sighted participants. Postural stability measurements were taken with open eyes (session I) and with closed eyes (session II). During each session, the mean velocity of the center of pressure (COP) displacements was determined using a force plate both before and after physical exercise. During testing with open eyes, the 2 groups did not differ significantly in terms of their postural response to physical exercise. When examined with closed eyes, the individuals who were visually impaired showed markedly greater postexercise increase in mean velocity of the COP displacement in the mediolateral direction. This intergroup difference was likely a consequence of significantly higher preexercise values of posturographic parameters observed in the sighted participants. More pronounced postexercise changes in the postural stability of sighted participants were associated with lower levels of physical activity and higher values of BMI. Further research is needed to explain the character of the abovementioned relationships in individuals who are visually impaired.