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These results show strong dose-response relationships between resistance training intensity and strength gains, and between strength gains and functional improvements after resistance training. Low-moderate intensity resistance training of the KE muscles may not be sufficiently robust from a physiologic perspective to achieve optimal improvement of functional performance. Supervised HI, free weight-based training for frail elders appears to be as safe as lower intensity training but is more effective physiologically and functionally.

Objective: To investigate the effect of weight loss on balance control in obese and morbid obese men. Methods: In a longitudinal and clinical intervention study, postural stability was measured with a force platform before and after weight loss in men. Weight loss was obtained in obese men (mean body mass index (BMI) ¼ 33.0 kg/m 2 ) by hypocaloric diet until resistance and in morbid obese men (mean BMI ¼ 50.5 kg/m 2 ) by bariatric surgery. Morbid obese men were tested before surgery, and 3 and 12 months after surgery when they had lost 20 and nearly 50% of initial body weight, respectively. Normal weight individuals (mean BMI ¼ 22.7 kg/m 2 ) were tested twice within a 6-to 12-month period to serve as control. Body fatness and fat distribution measures, and posturographic parameters of the center of foot pressure (CP) along the antero-posterior and medio-lateral axes for conditions with and without vision were performed in all subjects. Results: Weight loss averaged 12.3 kg after dieting and 71.3 kg after surgery. Body weight remained unchanged in the control group. After weight loss, nearly all measures of postural stability were improved with and without vision (i.e., CP speed and range in antero-posterior and medio-lateral axes). A strong linear relationship was observed between weight loss and improvement in balance control measured from CP speed (adjusted R 2 ¼ 0.65, Po0.001). Conclusion: Weight loss improves balance control in obese men and the extent of the improvement is directly related to the amount of weight loss. This should decrease the habitual greater risk of falling observed in obese individuals.

Objective Our objective was to explore the training-related knowledge, beliefs, and practices of athletes and the influence of lockdowns in response to the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods Athletes (n = 12,526, comprising 13% world class, 21% international, 36% national, 24% state, and 6% recreational) completed an online survey that was available from 17 May to 5 July 2020 and explored their training behaviors (training knowledge, beliefs/attitudes, and practices), including specific questions on their training intensity, frequency, and session duration before and during lockdown (March–June 2020). Results Overall, 85% of athletes wanted to “maintain training,” and 79% disagreed with the statement that it is “okay to not train during lockdown,” with a greater prevalence for both in higher-level athletes. In total, 60% of athletes considered “coaching by correspondence (remote coaching)” to be sufficient (highest amongst world-class athletes). During lockdown, < 40% were able to maintain sport-specific training (e.g., long endurance [39%], interval training [35%], weightlifting [33%], plyometric exercise [30%]) at pre-lockdown levels (higher among world-class, international, and national athletes), with most (83%) training for “general fitness and health maintenance” during lockdown. Athletes trained alone (80%) and focused on bodyweight (65%) and cardiovascular (59%) exercise/training during lockdown. Compared with before lockdown, most athletes reported reduced training frequency (from between five and seven sessions per week to four or fewer), shorter training sessions (from ≥ 60 to < 60 min), and lower sport-specific intensity (~ 38% reduction), irrespective of athlete classification. Conclusions COVID-19-related lockdowns saw marked reductions in athletic training specificity, intensity, frequency, and duration, with notable within-sample differences (by athlete classification). Higher classification athletes had the strongest desire to “maintain” training and the greatest opposition to “not training” during lockdowns. These higher classification athletes retained training specificity to a greater degree than others, probably because of preferential access to limited training resources. More higher classification athletes considered “coaching by correspondence” as sufficient than did lower classification athletes. These lockdown-mediated changes in training were not conducive to maintenance or progression of athletes’ physical capacities and were also likely detrimental to athletes’ mental health. These data can be used by policy makers, athletes, and their multidisciplinary teams to modulate their practice, with a degree of individualization, in the current and continued pandemic-related scenario. Furthermore, the data may drive training-related educational resources for athletes and their multidisciplinary teams. Such upskilling would provide athletes with evidence to inform their training modifications in response to germane situations (e.g., COVID related, injury, and illness).

Introduction: Obesity yields a decreased postural stability. The potentially negative impact of obesity on the control of upper limb movements, however, has not been documented. This study sought to examine if obesity imposes an additional balance control constraint limiting the speed and accuracy with which an upper limb goal-directed movement performed from an upright standing position can be executed. Method: Eight healthy lean subjects (body mass index (BMI) between 20.9 and 25.0 kg/m 2 ) and nine healthy obese subjects (BMI between 30.5 and 48.6 kg/m 2 ) pointed to a target located in front of them from an upright standing posture. The task was to aim at the target as fast and as precisely as possible after an auditory signal. The difficulty of the task was varied by using different target sizes (0.5, 1.0, 2.5 and 5.0 cm width). Hand movement time (MT) and velocity profiles were measured to quantify the aiming. Centre of pressure and segmental kinematics were analysed to document postural stability. Results: When aiming, the forward centre of pressure (CP) displacement was greater for the obese group than for the normal BMI group (4.6 and 1.9 cm, respectively). For the obese group, a decrease in the target size was associated with an increase in backward CP displacement and CP peak speed whereas for the normal BMI group backward CP displacements and CP peak speed were about the same across all target sizes. Obese participants aimed at the target moving their whole body forward whereas the normal BMI subjects predominantly made an elbow extension and shoulder flexion. For both groups, MT increased with a decreasing target size. Compare to the normal BMI group, this effect was exacerbated for the obese group. For the two smallest targets, movements were on average 115 and 145 ms slower for the obese than for the normal BMI group suggesting that obesity added a balance constraint and limited the speed with which an accurate movement could be done. Summary: Obesity, because of its effects on the control of balance, also imposes constraints on goal-directed movements. From a clinical perspective, obese individuals might be less efficient and more at risk of injuries than normal weight individuals in a large number of work tasks and daily activities requiring upper limb movements performed from an upright standing position.

Although there have been numerous studies examining the prevalence of overweight and obesity among children and adolescents with intellectual disabilities, they have not yet been integrated and synthesized through a systematic quantitative review process. The purpose of this systematic review and meta-analysis was to determine: (i) the prevalence of overweight/obesity among children and adolescents with intellectual disabilities; (ii) the sources of heterogeneity in studies reporting the prevalence of overweight/obesity in this population; and (iii) the risk of overweight/obesity in this population compared with their typically developing peers. A systematic literature search was performed and 16 studies, published between 1985 and 2015, met the inclusion criteria. The resulting pooled prevalence estimates for overweight, overweight-obesity and obesity were respectively: (i) 15%, 30%, and 13%, in children; and (ii) 18%, 33%, and 15% in adolescents. Subgroup analyses showed significant variations in the pooled prevalence estimates as a function of geographical region, recruitment setting, additional diagnoses, and norms used to define overweight or obesity. The findings also showed adolescents with intellectual disabilities to be respectively 1.54 and 1.80 times more at risk of overweight-obesity and obesity than typically developing adolescents. Unfortunately, no such comparison is available for children. © 2016 World Obesity.

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Objective: Overweight individuals sway more than normal weight individuals. Major weight loss improves their balance control despite a related decrease in muscle strength. Presumably, muscular strength is an important factor for balance control. This study investigated the effect that a change in body mass has on relative strength and balance control. Methodology: Force (isometric knee extension) and balance control (center of pressure speed and range) were studied in three groups; normal weight (BMI o25 kg m À2 ), obese (30 kg m À2 oBMIo 40 kg m À2 ) and excess obese (BMI 440 kg m À2 ) Caucasian male individuals. Results: The excess obese individuals who underwent bariatric surgery as a weight loss strategy were studied before, 3 and 12 months after losing on average, 66.9 kg ( ± 95% CI 55.8, 77.9 kg; on average, 45% of their weight). The obese individuals who underwent diet modifications were studied before dieting and when resistance to weight loss occurred after losing on average 11.7 kg ( ± 95% CI 9.3, 14.2 kg; on average, 12% of their weight). The control group was studied twice, 50 weeks apart. In obese and excess obese individuals, losing weight reduced absolute knee muscular strength on average, by 8.2 kg (±95% CI 3.9, 12.5 kg; on average, 10% of their strength) and 23.9 kg ( ± 95% CI 12.1, 35.8 kg; on average, 33% of their strength). However, it also increased balance control measured with speed of the center of foot pressure, on average, by 0.10 cm s -1 ( ± 95% CI 0.05, 0.14 cm s -1 ; or increased of 12%) and 0.28 cm s -1 ( ± 95% CI 0.07, 0.47 cm s -1 ; increased of 27%), respectively. Relative strength increased approximately by 22% for only the excess obese group 12 months post surgery. Conclusion: This suggests, in overweight individuals, weight loss is more efficient at improving balance control than increasing, or even maintaining muscle strength. In these individuals, training programs aimed at improving balance control should primarily target weight loss.