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Background: Ankle-foot orthoses (AFOs) are external devices that are prescribed forpeople who were diagnosed with muscle weakness in the lower extremities. Thesedevices are typically prescribed to accommodate the patients for their weak limb(s) byreducing toe-drag and improving ankle dorsiflexion. Previous work has looked at theeffects of an AFO on ankle muscle activity during gait. However, there is a lack ofinformation on how AFOs might influence knee muscle activity during gait underdifferent walking conditions. This study examined the effects of a common posterior leafspring plastic AFO (PAFO) and anterior shell carbon fiber AFO (CAFO) on knee muscleactivity in a healthy population during three different treadmill conditions. It washypothesized that the design of the CAFO, would create less demand on the kneeextensors than either the PAFO or no AFO for all walking conditions.Methods: 15 healthy young adults were recruited for this repeated measures study.Noraxon EMG sensors were used to measure the muscle activity of the rectus femoris(RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), andsemitendinosus (ST) while walking on a treadmill at a comfortable pace. Individualswalked with no AFO, a PAFO and a CAFO during three treadmill conditions (flat, incline, decline). Then, all EMG data were exported to and analyzed using MATLAB,where they were filtered, demeaned, rectified, normalized, and then averaged.Results: Separate one-way ANOVAs were used to identify significant (p

The objective of this study was to analyze pH changes within five lamb muscles and correlate those to the physical and biochemical characteristics of the muscles, meanwhile, to understand what drives the changes and determine the strength of the correlation in pH changes with meat quality properties. Semimembranosus (SM), semitendinosus (ST), longissimus dorsi (LD), infraspinatus (IS), and supraspinatus (SS) from six animals were analyzed. Muscles from the left side of the carcasses were excised at 4 hours post-mortem to measure the fiber type by electrophoresis, while muscles from the right side of the carcasses were used to measure pH and temperature at 1.5, 6, 8, and 24 hours, and color was measured after the muscles were excised at 24 hours. After that, muscles from the right side were aged for 7 days and checked for cooking loss and tenderness. SM, ST, and LD muscles presented predominantly type-IIa and -IIx fibers, while SS was more abundant in type-Ifiber, and IS presented more type-Ifiber than SM, ST, and LD, but less than SS. Temperature of all muscles decreased and reached 3°C. All the muscles followed the normal trend of post-mortem pH decline, with the largest extent in LD and relatively higher ultimate pH in IS and SS. ST was the lightest (P < 0.05) muscle, while SS was the reddest (P < 0.05) muscle in this study. After aging and cooking, SM presented the highest (P < 0.05) loss of water and was the toughest (P < 0.05) muscle, while IS had the lowest (P < 0.05) cooking loss and was the most tender (P < 0.05) muscle. These data show that the different muscles varied in their on post-mortem biochemical and physical changes, and the gel results indicate that the methodology developed is suitable for observing fiber types in lamb muscles.

The beef industry is continuously seeking ways to increase consumer demand, while improving eating quality and consistency of beef products through added value products. Thus, industry leaders are have introduced various “value cuts” to the marketplace through innovative cutting and muscle profiling in the last ten years at a moderate price. However, there has been little innovation in adding value through methods of cooking. Therefore, two experiments were designed to add value to an undervalued tough cut of beef through sous vide cooking. The first experiment was conducted to investigate the utility of sous vide cooking in beef tenderness, to ultimately add value to undervalued cuts of meat. The second experiment was performed to determine the effects of different temperature and time combinations on tenderness and to understand the effects of sous vide cooking on meat proteins.