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Biotensegrity
Published in Kohlstadt Ingrid, Cintron Kenneth, Metabolic Therapies in Orthopedics, Second Edition, 2018
Anatomy and biomechanics, then, are based on this frame. In fact, muscles are defined by what they do to bones. To understand muscle function, we learn origins and insertions on bones. As the muscle contracts and shortens, one bone moves in relation to another at a joint space. To control joint movement, we need rapid feedback from receptors in the tissue with rapid signaling back to the muscles to control how the bones move. This framing of the bones as the primary reference point persists even though it is demonstrably false. For example, the vastus lateralis muscle of the quadriceps is described as originating from the femur and inserting at the patella via the quadriceps tendon. Therefore, vastus lateralis is a knee extensor. Yet, a muscle twitch observed on dynamic ultrasonography (Figure 5.3 and Video 5.2) shows that part of the muscle “originates” at the lateral intermuscular septum. This part of the muscle is not pulling on a bone; it is pulling on connective tissue that also distorts other muscles. So, how do we understand movement now? To complicate matters further, the inferior gluteus maximus also tensions the lateral intermuscular septum [2]; so, two muscles shown as separate in standard anatomy texts are actually part of the same myofascial continuity (Figure 5.4).
Whey Protein and Essential Amino Acids Promote the Reduction of Adipose Tissue and Increased Muscle Protein Synthesis During Caloric Restriction-Induced Weight Loss in Elderly, Obese Individuals
Published in Chad Cox, Clinical Nutrition and Aging, 2017
Robert H. Coker, Sharon Miller, Scott Schutzler, Nicolaas Deutz, Robert R. Wolfe
Experimental Paradigm. Prior to initiation of the weight loss intervention, volunteers in both groups completed a testing session designed to examine the influence of EAAMR and CMR on skeletal muscle protein FSR. Subjects were instructed to fast after 2200 hrs, with water permitted. On the day of the testing session, subjects reported to the study site, and two intravenous catheters were inserted by our registered nurse. One catheter was utilized for the infusion of stable isotopes, while the other was utilized for blood sampling. A primed (2 μmol/kg), constant (0.07 μmol/ kg/min) infusion of ring- [13]C6-phenylalanine began after obtaining a background blood sample and the isotopic infusion was maintained for 6 hours. Blood was sampled at 20 min intervals to determine tracer enrichment and blood amino acid levels. A tissue biopsy of the vastus lateralis muscle was taken under local anesthesia at t = 60, 180 and 240 min [16]. Biopsies were utilized for the determination of skeletal muscle protein FSR by tracer methodology [17]. After the initial biopsy at t = 60 min, subjects were provided with a single dose of EAAMR or CMR. At t = 180 and t = 240 min, two biopsies were taken to evaluate the influence of EAAMR or CMR on the incorporation of the phenyalalnine tracer into the muscle.
Applied exercise physiology and health
Published in Nick Draper, Helen Marshall, Exercise Physiology, 2014
Prior to starting the training programmes the participants completed a 50 kJ and a 750 kJ ride, during which participants were required to cycle until they had expended the required kJ for each test. In addition, participants had a muscle biopsy taken from their vastus lateralis muscle. The same testing procedure was repeated at the end of the study. Results indicated that the time taken for the 750 kJ ride decreased by 10.1% for the SIT group and 7.5% for the ET group. The differences in the 50 kJ tests were smaller, with the SIT group 4.1% and the ET group 3.5% quicker to complete the test. The muscle biopsy findings indicated that participants in both groups significantly improved their muscle oxidative capacity, but despite the differences in training volumes, there were no statistical differences between the improvements for the SIT and ET groups. Similarly, muscle buffering capacity and glycogen content improved more for the SIT group than the ET group, but there were no statistical differences between the groups. The key conclusions from this study were that (a) fitness and metabolic markers improved when the total training volume was structured to enable time-saving and (b) that SIT provided an alternative form of training to traditional ET producing similar improvements in exercise performance, muscle oxidative capacity and buffering. Given these findings it appeared that HIIT training, in this case in the form of SIT, could provide a time-efficient training method for improving exercise performance for young active males.
Association of gross motor function and activities of daily living with muscle mass of the trunk and lower extremity muscles, range of motion, and spasticity in children and adults with cerebral palsy
Published in Developmental Neurorehabilitation, 2023
Mitsuhiro Masaki, Honoka Isobe, Yuki Uchikawa, Mami Okamoto, Yoshie Chiyoda, Yuki Katsuhara, Kunio Mino, Kaori Aoyama, Tatsuya Nishi, Yasushi Ando
In the present study, the mobility domain of the PEDI declined with decreased vastus lateralis muscle thickness. In the quadriceps femoris muscle, the activity of the vastus lateralis muscle increases from initial contact to loading response during walking.34,35 Furthermore, the physiological cross-sectional area of the vastus lateralis muscle is greatest in the quadriceps femoris muscle.36 The vastus lateralis muscle rather than the rectus femoris and vastus intermedius muscles may contribute to the extension movement of the knee joint in the standing position and during walking because the greater physiological cross-sectional area is advantageous to exert muscle strength. Thus, reduced PEDI mobility domain scores might be associated with decreased vastus lateralis muscle thickness in children and adults with CP as muscle strength of the vastus lateralis muscle is important for mobility such as walking. A previous study demonstrated the association between declined ADL assessed using the mobility area of the BI and decreased thickness of the rectus femoris muscle in children with CP.12 However, the results of the present study revealed the association between declined ADL assessed using the mobility domain of the PEDI and decreased vastus lateralis muscle thickness in children and adults with CP. The inconsistency of these results might be due to differences in age, ADL measurement methods, and statistical analyses between this study (children and adults, PEDI, and stepwise regression analysis) and the previous study (children, BI, and partial correlation analysis).
Benefits and interval training in individuals with spinal cord injury: A thematic review
Published in The Journal of Spinal Cord Medicine, 2022
David R. Dolbow, Glen M. Davis, Michael Welsch, Ashraf S. Gorgey
Two case studies, Dolbow and Credeur40 and Dolbow et al.41 investigated the effects of RG-HIIT-FES cycling on a 31-year-old female with motor complete T10 SCI and a 34-year-old male with motor complete T9 SCI for ten weeks and eight weeks, respectively. Both programs included 30-minute HIIT sessions thrice weekly. After ten weeks of RG-HIIT-FES cycling, Dolbow and Credeur found an increase in total body lean mass (2.8%) and lean mass of the legs (5.9%). In fact, a 59.5% increase in vastus lateralis muscle thickness was observed. In addition to the body composition changes, improved vascular health was observed as evidenced by a 147.7% increase in flow-mediated dilation of the brachial artery and an 11.1% increase in reactive hyperemia. Dolbow et al.41 also reported improvements in brachial artery flow mediated dilation in the second case report, although there were no changes in body composition. In each case report, the exercise training stimulus was well tolerated, and successfully completed without any adverse events.
Endurance training alters YKL40, PERM1, and HSP70 skeletal muscle protein contents in men with type 2 diabetes mellitus
Published in Endocrine Research, 2019
Christian Brinkmann, Anika Kuckertz, Thorsten Schiffer, Wilhelm Bloch, Hans-Georg Predel, Klara Brixius
The patients underwent a medical check before being enrolled in the study. They participated in a 3-month ergometer endurance training program. The subjects’ data were analyzed: 6 weeks pre-training (T1), 1 week pre-training (T2), and 3–4 days after the 3-month training intervention (T3). The time period between T1 and T2 was used as a control period (instead of using a passive control group) to detect possible variations in the measured variables. Having the subjects serve as their own controls prior to treatment was considered more ethical than using a traditional two-group design, because it does not require taking biopsies from inactive subjects who do not benefit from participating in a study as passive controls. Subjects were instructed to not engage in any physical training during the 6 weeks prior to the training intervention. Furthermore, all subjects were instructed to not change their dietary habits during the study period. The following procedures were performed at T1, T2, and T3: venous blood was collected after a 12-hour overnight fast and before medication intake in the early morning. Shortly thereafter, muscle tissue was obtained from the vastus lateralis muscle. A few days later, the subjects’ physical performance was tested on a cycle ergometer.