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Objective Sleep apnea research cites that an oral appliance, which places the mandible in a more forward position and the genioglossus (tongue muscle) on the floor of the mouth, improves aspects of the pharyngeal opening. Exercise science research has cited improvements in airway dynamics and physiological variables with oral appliance use during exercise. Thus, the purpose of this study was to design an oral appliance that would act on the genioglossus and determine if there were effects on respiratory parameters while exercising. Materials and methods Seventeen healthy subjects ages 18–43 participated in this study. Prior to the exercise protocol, the order of the oral applicance (OA) or no oral appliance (no OA) condition was randomly assigned to subjects, with subjects completing both conditions. Respiratory parameters (respiratory rate, ventilation, oxygen, and carbon dioxide) were measured between conditions while subjects ran for 10 min at steady state. Results The results demonstrated that both respiratory rate (25.97 BPM, OA and 28.35 BPM, no OA) and ventilation (47.66 l/min, OA and 50.34 l/min, No OA) were significantly lowered (p < .01) in the OA condition. There were no differences in carbon dioxide (1.89 l/min, no OA and 1.88 l/min, OA) or oxygen outcomes (2.17 l/min, no OA and 2.17 l/min OA). Discussion The outcomes from this study suggest that the design of the oral appliance elicits an effect on the genioglossus, thereby resulting in lowered respiratory rate and ventilation with no negative effects on oxygen uptake during exercise.

Spinal cord injury (SCI) is associated with devastating neurological deficits affecting more than 11,000 Americans each year. Although several therapeutic agents have been proposed and tested, no FDA-approved pharmacotherapy is available for SCI treatment. We have recently demonstrated that estrogen (E2) acts as an antioxidant and anti-inflammatory agent, attenuating gliosis in SCI. We have also demonstrated that nanoparticle-mediated focal delivery of E2 to the injured spinal cord decreases lesion size, reactive gliosis, and glial scar formation. The current study tested in vitro effects of E2 on reactive oxygen species (ROS) and calpain activity in microglia, astroglia, macrophages, and fibroblasts, which are believed to participate in the inflammatory events and glial scar formation after SCI. E2 treatment decreased ROS production and calpain activity in these glial cells, macrophages, and fibroblast cells in vitro. This study also tested the efficacy of fast- and slow-release nanoparticle-E2 constructs in a rat model of SCI. Focal delivery of E2 via nanoparticles increased tissue distribution of E2 over time, attenuated cell death, and improved myelin preservation in injured spinal cord. Specifically, the fast-release nanoparticle-E2 construct reduced the Bax/Bcl-2 ratio in injured spinal cord tissues, and the slow-release nanoparticle-E2 construct prevented gliosis and penumbral demyelination distal to the lesion site. These data suggest this novel E2 delivery strategy to the lesion site may decrease inflammation and improve functional outcomes following SCI.

A spinal cord injury (SCI) may lead to loss of strength, sensation, locomotion and other body functions distal to the lesion site. Individuals with SCI also develop secondary conditions due to the lack of skeletal muscle activity. As SCI case numbers increase, recent studies have attempted to determine the best options to salvage affected musculature before it is lost. These approaches include pharmacotherapeutic options, immunosuppressants, physical activity or a combination thereof. Associated biomarkers are increasingly used to determine if these treatments aid in the protection and reconstruction of affected musculature.

Qualitative assessments of the blink reflex are used clinically to assess neurological status in critical care, operating room, and rehabilitative settings. Despite decades of literature supporting the use of quantitative measurements of the blink reflex in the evaluation of multiple neurological disorders, clinical adoption has failed. Thus, there remains an unmet clinical need for an objective, portable, non-invasive metric of neurological health that can be used in a variety of settings. We have developed a high-speed videography-based device to trigger, record, and analyze a blink reflex. A pilot study was performed to compare the device’s measurements to the published literature of electromyographic measurements, currently the gold standard. The study results indicate that the device is a viable tool to obtain fast, objective, and quantitative metrics of a blink reflex, and has promise as a non-invasive diagnostic assessment of neurological health., The positions of the right (red) and left (blue) eyelids during a stimulated blink are tracked over time using image processing. The technique produces rapid, non-invasive, and objective measurements of blink parameters, making it a useful tool for assessing neurological function.

Studies have demonstrated positive results for people who practice traditional yoga, specifically in body mass index, depression, cancer, sleeping patterns, and diabetes. Most forms of traditional yoga are held in a temperate climate between 293 Kelvin (K) to 295 K; a temperature that is calming and places little stress on the body. Bikram yoga, however, is a more intense form of yoga performed in a hotter climate, typically at 314 K with 40% humidity. The purpose of this study was to determine how Bikram yoga affected blood pressure, body composition, and sleep patterns in beginner and intermediate/experienced practitioners. Participants (N=16) completed 8 weeks of sessions, ranging between 2 to 7 classes per week in a local Bikram yoga program conducted by certified instructors. All participants were assessed prior to the study and again at the end of the eight weeks. A BOD POD (an air displacement plethysmography) was used for body composition assessments, while a digital blood pressure cuff was used to assess blood pressure. In addition, participants were also surveyed on sleep parameters pre and post yoga participation. In combining all subjects, results showed there was a significant improvement (p=0.054) in faster time to fall asleep (27.66 min pre and 23.967 min post), and a trend (p=0.057) towards improved mean arterial pressure (92.20 mmHg pre and 88.33 mm Hg post). There were no differences in weight loss or percent body fat in subjects. This study indicates that there is a trend towards improved blood pressure and significant improvement in sleep parameters after 8 weeks of Bikram yoga for both intermediate/experienced and beginners, but no differences in body composition.

The Centers for Disease Control and Prevention estimates 1.6–3.8 million concussions occur each year. Research cites that 21% of traumatic brain injury in children/youth results from participation in sports and recreational activities. However, current methods to assess concussion, which includes balance, neurocognitive, and self-report assessments, provide conflicting validity and reliability. Thus, many sports medicine professionals seek more objective measures to assess the severity and outcomes of a concussive event. The purpose of this study was to utilize a novel technology to determine if there were differences in blink reflex parameters among baseline, active, and concussed athletes. Twenty-four Division I football athletes participated in this study. Routine pre-season baseline data were collected on athletes as well as assessments of their blink reflex parameters using a blink reflexometer. Significant differences were found in blink parameters between baseline and active measurements in latency, differential latency, lid velocity, log of time to open, log of number of oscillations, and log of total blink time. In addition, significant differences were found between baseline and post-head impact in latency, differential latency, log of time to open, and log of number of oscillations. In comparing head impact and active play, blink latency decreased with head impact but increased in active play and differential latency and log of number of oscillations increased with head impact but decreased in active play. The results of this study suggest that use of a blink reflexometer provides quantifiable and objective outcomes to complement the concussion assessment protocol for athletes.

Recent reports suggest the use of mouthpieces may be beneficial at improving aerobic and anaerobic exercise performance. However, the mechanisms of these reported improvements have yet to be elucidated. The purpose of this study was to explore the possible mechanisms of improved performance using the ArmourBite® mouthpiece. Using a within subject randomized treatment design, 15 experienced resistance trained males (19–26 years of age) performed 6 sets of 10 repetitions of free weight back squats at 80% of 1RM with and without a mouthpiece. Blood samples were collected before exercise, after 3 sets (Mid), immediately post (Post), 30 min post (Post-30), 60 min post (Post-60) and 120 min post (Post-120) exercise. Samples were analyzed for lactate and ELISA was used to determine cortisol. Mouthpiece use resulted in more repetitions completed without assistance (54.36 ± 0.61 vs. 53.27 ± 0.79, p = 0.046) and fewer assisted repetitions (6.73 ± 0.79 vs. 5.64 ± 0.61 repetitions, p = 0.046) compared to the control group. Lactate concentrations were lower in the treatment vs. control group at the Post (11.54 ± 2.23 vs. 13.07 ± 2.96 mmol/L, p = 0.023) Post- 30 (4.45 ± 1.94 vs. 5.41 ± 1.90 mmol/L, p = 0.021), and Post-60 (2.07 ± 0.94 vs. 2.55 ± 0.96 mmol/L, p = 0.048) sampling periods. Mouthpiece use lowered cortisol levels at Mid and Post-30 (19.39 ± 6.90 vs. 27.84 ± 14.56 μg/dL, p = 0.02 (22.91 ± 8.47 vs. 31.81 ± 10.79 μg/dL, p = 0.04). Cortisol AUC values showed significant differences within the AUC Pre-Post control and treatment (55.16 ± 23.84 vs. 41.95 ± 2.65 μg/dL, p = 0.02) groups. These data suggest that mouthpiece use may increase performance and decrease stress when used during intense resistance exercise.

The aim of this study was to assess the relationships between human muscle fiber hypertrophy, protein isoform content, and maximal Ca2+-activated contractile function following a short-term period of resistance exercise training. Six male subjects (age 27 ± 2 yr) participated in a 12-wk progressive resistance exercise training program that increased voluntary lower limb extension strength by >60%. Single chemically skinned fibers were prepared from pre- and posttraining vastus lateralis muscle biopsies. Training increased the cross-sectional area (CSA) and peak Ca2+-activated force (Po) of fibers containing type I, IIa, or IIa/IIx myosin heavy chain by 30–40% without affecting fiber-specific force (Po/CSA) or unloaded shortening velocity (Vo). Absolute fiber peak power rose as a result of the increase in Po, whereas power normalized to fiber volume was unchanged. At the level of the cross bridge, the effects of short-term resistance training were quantitative (fiber hypertrophy and proportional increases in fiber Poand absolute power) rather than qualitative (no change in Po/CSA, Vo, or power/fiber volume).

Purpose: We compared the functional properties of muscle fibers from two groups of subjects that differed widely in their training history to investigate whether long-term resistance exercise alters the intrinsic contractile properties of skeletal muscle fibers. Methods: Vastus lateralis muscle biopsies were obtained from six sedentary males (NT group, age = 23 ′ 1 yr) and six males who had participated in regular resistance exercise training over the preceding 7.6 ′ 1.6 yr (RT group, 22 ′ 1 yr). Chemically skinned muscle fiber segments were activated with a saturating free [Ca 2 + ] to quantify fiber peak Ca 2 + -activated force (P o ), unloaded shortening velocity (V o ), and peak power. Fiber segment myosin heavy chain (MHC) isoform content was identified by gel electrophoresis. Results: Slow and fast fibers from the RT group were larger in CSA and produced greater absolute P o and absolute peak power in comparison with fibers from the NT group. However, these differences were no longer evident after P o and peak power were normalized to fiber CSA and fiber volume, respectively. V o /fiber length was dependent on fiber MHC content but independent of training status. Conclusion: Fiber hypertrophy was sufficient to account for intergroup differences in P o and peak power of slow and fast fibers. There was no evidence that the intrinsic contractility of slow or fast fibers, as evaluated by force, shortening velocity, and power normalized to the appropriate fiber dimensions, differed between RT and NT groups.

We tested the hypothesis that cross-bridge mechanisms of contraction differed in early postmenopausal women who did or did not receive hormone replacement therapy (HRT). Vastus lateralis biopsies were obtained from 17 postmenopausal women (49–57 years old), 8 of whom were on HRT for the previous 24 ± 5 months and 9 of whom were never on HRT. Electrophoresis and enzyme histochemistry revealed that fiber myosin heavy chain (MHC) isoform distribution, the cross-sectional area (CSA) of slow and fast fibers, and the relative CSA occupied by each, were similar for HRT and non-HRT groups. Single permeabilized fibers containing type IIa MHC had greater Ca2+-activated peak specific force, unloaded shortening velocity, and peak power than fibers containing type I MHC, but in all cases the values for HRT and non-HRT groups were similar. In this cross-sectional study, we found no evidence that Ca2+-activated fiber function, MHC isoform distribution, or relative CSA occupied by slow and fast fibers differed between HRT and non-HRT groups.