Forward acceleration is an important factor to control in biomechanics studies investigating walking/running, as human kinetics and kinematics vary with changes in acceleration. During overground running studies, acceleration is typically estimated using the net anterior-posterior ground reaction force impulse, as measured with force plates. However, as studies move outside the lab, there is limited validation of alternative methods of quantifying acceleration when force plates are unavailable. The purpose of this study was to assess the validity of alternative methods for estimating acceleration in overground running. We evaluated the use of timing lights and motion capture, as indicators of acceleration, to measure change in velocity. We hypothesized that the change in velocity calculated from timing lights and motion capture markers near the center of mass would have a strong positive correlation with the relative anterior-posterior ground reaction force impulse measured with force plates. Ten participants ran in an indoor lab while measurements were collected using timing lights, motion capture and a force plate. The correlation between the relative anterior-posterior impulse and velocity changes measured by timing lights was weak (r = -0.01, r = 0.27 and r = 0.15, respectively). In contrast, the correlation between the relative anterior-posterior impulse and velocity change determined by motion capture was strong (r = 0.81). In studies where force plates are not available, measuring changes in velocity with motion capture is a promising method for calculating and controlling acceleration. However, measuring changes in velocity with timing lights does not show as much promise due to weak correlation values and should therefore be avoided.

When it comes to the medical field, 3D modeling has previously been used to render anatomical images in greater detail in order to better understand bodily functions. Lately, however, 3D modeling has made waves in depicting diseases, with a focus on their severity and progression. Unlike a model depicting computer graphics, 3D culture models allow cells to interact in three dimensions and better display cell growth and movement, according to the Food and Drug Administration. Culture models are beneficial in replicating the complexities of disease by promoting interactions between cells and providing insight into potential solutions. In this issue of the Journal of Young Investigators, Priscilla Detwieler and her colleagues demonstrate that atelocollagen incorporated in a 3D model is shown to simulate a potential treatment for inflammation-induced osteoarthritis.  

Over the past decade, there have been many significant advances in the field of skin aging, including studies that explore the clearance of senescent (growth-arrested) cells in skin, regenerative therapeutics, and even 3D bioprinting of skin. One of the latest discoveries showed that blocking Interleukin 17 (IL-17) signaling leads to delays in the skin aging process. But how does IL-17, a pro-inflammatory cytokine, delay what has been known as the inevitable hallmarks of skin aging? 

To combat the harmful effects of stress, neuroscientists are pointing to mindfulness, defined as the practice of being fully present and aware of our external environment and our actions, while not being overly reactive or overwhelmed by external events. To shed light on this, JYI interviewed renowned neuroscientist Dr. Alexandra Fiocco, whose expertise lies at the intersection of mindfulness, stress, and cognitive aging. Dr. Fiocco currently does research at Stress and Healthy Aging Research (StAR) Lab and teaches at Toronto Metropolitan University.