Female Athlete Triad and Relative Energy Deficiency in Sport: A Focus on Scientific Rigor We examine the scientific evidence supporting The Female Athlete Triad and Relative Energy Deficiency in Sport (RED-S) syndromes. More research is necessary to advance the understanding of both syndromes; however, it is premature to consider RED-S as an evidence-based syndrome. Future research should specifically define RED-S components, determine its clinical relevance, and establish the causality of relative energy deficiency on RED-S outcomes. Priscilla M. Clarkson 2019 Undergraduate Travel Award No abstract available

A Framework to Evaluate Devices That Assess Physical Behavior Body-worn devices that estimate physical behavior have tremendous potential to address key research gaps. However, there is no consensus on how devices and processing methods should be developed and evaluated, resulting in large differences in summary estimates and confusion for end users. We propose a phase-based framework for developing and evaluating devices that emphasizes robust validation studies in naturalistic conditions.

Carbohydrate Availability as a Regulator of Energy Balance With Exercise We explore the novel hypothesis that carbohydrate availability is involved in the regulation of energy balance with exercise, via hormonal and neural signals. We propose that carbohydrate availability could play a direct mechanistic role and partially explain previously documented relations between a more active lifestyle and tighter control of energy balance.

Training-Induced Neural Plasticity and Strength Are Amplified After Stroke Following stroke, sensorimotor brain networks and descending regulation are compromised but spinal interlimb neural connections remain morphologically intact. After cross-education strength and locomotion training, amplified neural plasticity and functional responses are observed in chronic stroke compared with neurologically intact participants. We hypothesize that poststroke neuroplasticity is amplified because of the involvement of interlimb neural connections that persist from our quadrupedal ancestry.

Overuse Injury: The Result of Pathologically Altered Myofascial Force Transmission? Overuse injuries are suggested to result from repetitive microdamage eliciting pain in the affected tissue. Therapy commonly focuses on the area of symptom localization; however, such approach may oversimplify the true etiopathology. This review hypothesizes that the development of some sports-related soft tissue disorders, such as plantar fasciitis or lumbago, is promoted by pathologically altered force transmission from anatomically connected structures.

Exoskeletons Improve Locomotion Economy by Reducing Active Muscle Volume Exoskeletons that improve locomotion economy typically are engineered to reduce users’ limb joint mechanical work or moments. Yet, limb joint dynamics do not necessarily reflect muscle dynamics, which dictate whole-body metabolic energy expenditure. Here, we hypothesize that exoskeletons primarily reduce user metabolic energy expenditure across locomotion conditions by reducing active muscle volume.

Macrophage Regulation of Muscle Regrowth From Disuse in Aging Skeletal muscle immune cells, such as macrophages, are necessary for proper regrowth after muscle disuse. We suggest that the important role of macrophages concerning muscle regrowth after disuse is divergent compared with young mice (i.e., dysregulated) during the recovery period. Modulation of macrophages may be a promising future therapeutic target to enhance the impaired muscle growth during recovery from disuse in older adults.

Transcallosal Control of Bilateral Actions The corpus callosum is an important neural structure for controlling and coordinating bilateral movements of the upper limbs; however, there remains a substantial lack of knowledge regarding its association with lower limb control. We argue that transcallosal structure is an integral neural mechanism underlying control of the lower limbs and callosal degradation is a key contributor to mobility declines.

The Overlooked Role of Fiber Length in Mechanical Load-Induced Growth of Skeletal Muscle No abstract available