de Heer, HD, Kaufman, A, Repka, CP, Rojas, K, Charley, B, and Bounds, R. AlterG Anti-Gravity Treadmill accuracy of unloading is affected by support frame height. J Strength Cond Res 35(10): 2910–2914, 2021—The AlterG Anti-Gravity Treadmill uses air pressure to provide partial body-weight support (BWS), lowering impact forces and metabolic demand of walking and running. Users wear specialized shorts that zip onto a bag supported by a metal bar frame covering the treadmill. The frame is placed at hip height in positions numbered 1–9, adjusted up or down based on preference. Machine accuracy in providing BWS is important to achieve desired training effects, but it is unknown whether frame placement impacts accuracy. Twenty subjects (10 men/women) were weighed in 10% increments from 0 to 60% BWS with the frame at hip height (iliac crest), the “neutral” position, and reweighed with the frame placed up to 3 numbers above or below hip height. Although the machine displayed the same proportion BWS, placing the frame higher than the neutral position resulted in significantly more support, whereas placing the frame lower led to less support. At 10% BWS, placing the frame 3 positions higher resulted in 3% more support compared with the neutral position (13.1% BWS, p < 0.001) and 3 positions lower in 4.7% less support (5.3% BWS, p < 0.001). Deviances were greater with more BWS. At 60% BWS, 3 positions higher than neutral resulted in 71.2% BWS (11.2% more than expected, p < 0.001) and 3 below 48.1% BWS (12.9% below expected, p < 0.001), total 24.1% difference. These findings suggest that the position of the support frame significantly impacts the AlterG accuracy in providing BWS, with placement higher than hip height resulting in more support than displayed by the machine and lower placement resulting in less support.

RESUMENObjetivo: evaluar la percepción de la sonrisa desde la perspectiva de los ortodoncistas y de las personas sin conocimientos de ortodoncia. Materiales y métodos: se realizó un estudio de corte transversal para lo cual se diligenciaron 207 cuestionarios de conocimientos y percepción de la sonrisa, por 43 ortodoncistas y estudiantes de la Especialización en Ortodoncia de la Universidad Santo Tomás (grupo 1) y 164 personas sin conocimientos de ortodoncia (grupo 2). Las variables de salida fueron la percepción de alteraciones en la línea media y en el corredor bucal; las variables explicatorias fueron la edad, el sexo y la condición socioeconómica. La información se describió mediante promedios y desviación estándar, y frecuencias y porcentajes según la naturaleza de las variables. Se aplicó la prueba de Chi cuadrado y se consideró un valor de p<0,05 como estadísticamente significativo.Resultados: la línea media con desviación de 1 mm y la centrada fueron las que más agradaron a hombres y mujeres, en los dos grupos de estudio. Al determinar la sonrisa menos agradable, los grupos coincidieron en que fue la de mayor desviación (4 mm). Se encontró asociación entre el conocimiento y la percepción de la desviación de la línea media en 2 mm (p=0,044) y 4 mm (p=0,000). Sonrisas con un corredor bucal amplio, medio y medio amplio son percibidas como menos agradables para ambos sexos, la totalidad de las mujeres valoró el corredor bucal amplio como menos agradable.Conclusión: no se presentó una diferencia estadísticamente significativa en la percepción de las características de la sonrisa entre personas sin y con conocimientos de ortodoncia [Torres MC, Barreto K, Polanco AM, Peña LL, Álvarez CM. Evaluación de la percepción de la sonrisa en personas con y sin conocimientos en ortodoncia. Ustasalud. 2014; 13: 32 -39] Palabras clave: sonrisa, ortodoncia, percepción. PERCEPTION OF THE SMILE ON PEOPLE WITH AND WITHOUT KNOWLEDGE IN ORTHODONTICS ABSTRACTObjective: to assess the perception of the smile from the perspective of orthodontists and people without knowledge in orthodontics. Methods: a cross-sectional study was carried out. Two hundred and seven questionnaires about knowledge and perception of the smile were completed by 43 orthodontists and students of the Especialización en Ortodoncia at the Universidad Santo Tomás (group 1) and 164 people with no knowledge in orthodontics (group 2). The dependent variables were the perception of alterations in the midline and the buccal corridor; the explanatory variables were age, sex and socioeconomic status. The information was described by means and standard deviations, frequencies and percentages depending on the nature of the variables. Chi-square test was applied and a p value <0.05 was considered statistically significant.Results: the midline deviation of 1 mm and centered were chosen for men and women as the most pleased the two study groups. In determining the least pleasant smile, the groups agreed that the least pleasant smile was when it presented the largest deviation...