RESUMEN

Texting while walking (TWW) is a dual-task activity that young adults perform in their everyday lives. TWW has been reported to affect gait characteristics such as gait speed, stride length, and cadence. However, the influence of TWW on lower extremity gait function has not been investigated. Therefore, the purpose of this study was to quantify gait function by examining gait symmetry and using a time series analysis. Twenty-eight young adults (14 males, 14 females) walked at their preferred speed for 10 m as a baseline condition and a 10 m TWW task. Three-dimensional segment tracking was achieved utilizing a lower extremity and trunk marker set and the Model Statistic was used to test for statistical differences between the hip, knee, and ankle angular joint positions. The hip yielded the most asymmetries (25 out of 101 points) throughout the gait cycle, while asymmetries for the knee and ankle joints yielded 16 out of 101 points and 11 out of 101 points, respectively. The outcomes of this study suggest there are differences between baseline and TWW gait symmetry, however, the percentage of the gait cycle affected was less than 25 % - indicating gait function is not strongly influenced by texting while walking in young adults.

Asunto(s)

Marcha , Extremidad Inferior , Envío de Mensajes de Texto , Caminata , Humanos , Masculino , Femenino , Adulto Joven , Marcha/fisiología , Caminata/fisiología , Fenómenos Biomecánicos , Adulto , Extremidad Inferior/fisiología , Articulación del Tobillo/fisiología , Velocidad al Caminar/fisiología , Articulación de la Rodilla/fisiología , Articulación de la Cadera/fisiología

RESUMEN

Laboratory-based gait analyses traditionally analyze baseline characteristics in individuals while they are barefoot. However, there is limited evidence on whether individuals' preferred walking shoes alter lower extremity kinematics during over-ground walking. We present novel evidence regarding the effects of shoes on lower extremity kinematics in healthy, young adults. Fifteen volunteers participated in this study which obtained lower extremity kinematic data on two over-ground walking conditions (barefoot and preferred shoes). Gait velocity, stance width, and stride length, along with sagittal plane hip, knee, and ankle angular positions were computed; hip, knee, and ankle positions were normalized to 100% of the stride. Dependent t-tests were used to compare baseline and shoe conditions for gait velocity and stance width; a two-way analysis of variance was used for stride length. A point-by-point Model Statistic analysis was used to identify significant differences in angular joint positions between conditions. Our results indicate that shoes affected the ankle angular joint position for more than half of the gait cycle, and affected the knee angular joint position, but only for approximately 20% of the cycle. The hip was unaffected by shoes. Gait velocity and stance width were statistically significant, with gait velocity being greater for shoes, and stance width being greater while barefoot. Stride length was not statistically significant between conditions. These outcomes suggest that researchers should use caution if they are considering a barefoot condition as a 'baseline' for healthy, young adults, as there are marked changes in the ankle, and in traditional gait metrics.

RESUMEN

A triathlon wetsuit is an important piece of equipment during the swim portion of the triathlon for the benefits of thermoregulation and additional buoyancy. However, a lack of knowledge exists about whether or not shoulder muscle activity is influenced by wearing a wetsuit. The purpose of this study was to determine if there were changes in shoulder muscle activity during front crawl with four different wetsuit conditions: Full sleeve (FSW), Sleeveless (SLW), Buoyancy shorts (BS), No wetsuit (NWS) in three different subjective swimming paces (slow, medium, and fast). Eight subjects (5 males, 3 females: mean ± SD, age = 39.1 ± 12.5 years; height = 1.8 ± 0.1 m; mass = 74.6 ± 12.9 kg; percent body fat = 19.0 ± 7.8%) completed twelve total swim conditions (4 wetsuits x 3 swimming pace) in a 25-m indoor pool. Muscle activity in anterior deltoid (AD) and posterior deltoid (PD) were measured using a wireless waterproofed electromyography (EMG) system. Stroke rate (SR) was calculated using the time to complete five-stroke cycles. The AD, PD EMG, and SR were compared using ANOVA with repeated measures. None of the dependent variables showed the interaction between wetsuit conditions and swimming paces (p > 0.05). Both AD and PD muscle activity as well as SR were influenced by swimming pace (p < 0.05) but not wetsuit conditions (p > 0.05). In conclusion, shoulder muscle activity and SR were not influenced by types of wetsuits but influenced by swimming pace.