@article{45159, author = {{Sherman, David A. and Baumeister, Jochen and Stock, Matt S. and Murray, Amanda M. and Bazett-Jones, David M. and Norte, Grant E.}}, issn = {{1388-2457}}, journal = {{Clinical Neurophysiology}}, keywords = {{Physiology (medical), Neurology (clinical), Neurology, Sensory Systems}}, pages = {{88--99}}, publisher = {{Elsevier BV}}, title = {{{Brain activation and single-limb balance following anterior cruciate ligament reconstruction}}}, doi = {{10.1016/j.clinph.2023.02.175}}, volume = {{149}}, year = {{2023}}, } @article{33389, abstract = {{Abstract Purpose Space flight and bed rest (BR) lead to a rapid decline in exercise capacity. Whey protein plus potassium bicarbonate diet-supplementation (NUTR) could attenuate this effect by improving oxidative metabolism. We evaluated the impact of 21-day BR and NUTR on fatigue resistance of plantar flexor muscles (PF) during repeated shortening contractions, and whether any change was related to altered energy metabolism and muscle oxygenation. Methods Ten healthy men received a standardized isocaloric diet with (n = 5) or without (n = 5) NUTR. Eight bouts of 24 concentric plantar flexions (30 s each bout) with 20 s rest between bouts were employed. PF muscle size was assessed by means of peripheral quantitative computed tomography. PF muscle volume was assessed with magnetic resonance imaging. PF muscle force, contraction velocity, power and surface electromyogram signals were recorded during each contraction, as well as energy metabolism (31P nuclear magnetic resonance spectroscopy) and oxygenation (near-infrared spectroscopy). Cardiopulmonary parameters were measured during an incremental cycle exercise test. Results BR caused 10–15% loss of PF volume that was partly recovered 3 days after re-ambulation, as a consequence of fluid redistribution. Unexpectedly, PF fatigue resistance was not affected by BR or NUTR. BR induced a shift in muscle metabolism toward glycolysis and some signs of impaired muscle oxygen extraction. NUTR did not attenuate the BR-induced-shift in energy metabolism. Conclusions Twenty-one days’ BR did not impair PF fatigue resistance, but the shift to glycolytic metabolism and indications of impaired oxygen extraction may be early signs of developing reduced muscle fatigue resistance. }}, author = {{Bosutti, Alessandra and Mulder, Edwin and Zange, Jochen and Bühlmeier, Judith and Ganse, Bergita and Degens, Hans}}, issn = {{1439-6319}}, journal = {{European Journal of Applied Physiology}}, keywords = {{Physiology (medical), Public Health, Environmental and Occupational Health, Orthopedics and Sports Medicine, General Medicine, Public Health, Environmental and Occupational Health, Physiology}}, number = {{5}}, pages = {{969--983}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Effects of 21 days of bed rest and whey protein supplementation on plantar flexor muscle fatigue resistance during repeated shortening contractions}}}, doi = {{10.1007/s00421-020-04333-5}}, volume = {{120}}, year = {{2020}}, } @article{30116, author = {{Gölz, Christian Johannes and Voelcker-Rehage, Claudia and Mora, Karin and Reuter, Eva-Maria and Godde, Ben and Dellnitz, Michael and Reinsberger, Claus and Vieluf, Solveig}}, issn = {{1664-042X}}, journal = {{Frontiers in Physiology}}, keywords = {{Physiology (medical), Physiology}}, publisher = {{Frontiers Media SA}}, title = {{{Improved Neural Control of Movements Manifests in Expertise-Related Differences in Force Output and Brain Network Dynamics}}}, doi = {{10.3389/fphys.2018.01540}}, volume = {{9}}, year = {{2018}}, } @article{41968, author = {{Scheer, Volker and Vieluf, Solveig and Cramer, Leoni and Jakobsmeyer, Rasmus and Heitkamp, Hans-Christian}}, issn = {{1664-042X}}, journal = {{Frontiers in Physiology}}, keywords = {{Physiology (medical), Physiology}}, publisher = {{Frontiers Media SA}}, title = {{{Changes in Running Economy During a 65-km Ultramarathon}}}, doi = {{10.3389/fphys.2018.01809}}, volume = {{9}}, year = {{2018}}, } @article{33394, abstract = {{ The effectiveness of whey protein plus potassium bicarbonate-enriched diet (WP+KHCO3) in mitigating disuse-induced changes in muscle fiber oxidative capacity and capillarization was investigated in a 21-day crossover design bed rest study. Ten healthy men (31 ± 6 yr) once received WP+KHCO3 and once received a standardized isocaloric diet. Muscle biopsies were taken 2 days before and during the 19th day of bed rest (BR) from the soleus (SOL) and vastus lateralis (VL) muscle. Whole-body aerobic power (V̇o2 max), muscle fatigue, and isometric strength of knee extensor and plantar flexor muscles were monitored. Muscle fiber types and capillaries were identified by immunohistochemistry. Fiber oxidative capacity was determined as the optical density (OD) at 660 nm of succinate dehydrogenase (SDH)-stained sections. The product of fiber cross-sectional area and SDH-OD (integrated SDH) indicated the maximal oxygen consumption of that fiber. The maximal oxygen consumption supported by a capillary was calculated as the integrated SDH in its supply area. BR reduced isometric strength of knee extensor muscles ( P < 0.05), and the fiber oxidative capacity ( P < 0.001) and V̇o2 max ( P = 0.042), but had no significant impact on muscle capillarization or fatigue resistance of thigh muscles. The maximal oxygen consumption supported by a capillary was reduced by 24% in SOL and 16% in VL ( P < 0.001). WP+KHCO3 attenuated the disuse-induced reduction in fiber oxidative capacity in both muscles ( P < 0.01). In conclusion, following 19 days of bed rest, the decrement in fiber oxidative capacity is proportionally larger than the loss of capillaries. WP+KHCO3 appears to attenuate disuse-induced reductions in fiber oxidative capacity. }}, author = {{Bosutti, Alessandra and Salanova, Michele and Blottner, Dieter and Bühlmeier, Judith and Mulder, Edwin and Rittweger, Jörn and Yap, Moi Hoon and Ganse, Bergita and Degens, Hans}}, issn = {{8750-7587}}, journal = {{Journal of Applied Physiology}}, keywords = {{Physiology (medical), Physiology}}, number = {{4}}, pages = {{838--848}}, publisher = {{American Physiological Society}}, title = {{{Whey protein with potassium bicarbonate supplement attenuates the reduction in muscle oxidative capacity during 19 days of bed rest}}}, doi = {{10.1152/japplphysiol.00936.2015}}, volume = {{121}}, year = {{2016}}, } @article{33398, author = {{Mulder, E. and Clément, G. and Linnarsson, D. and Paloski, W. H. and Wuyts, F. P. and Zange, J. and Frings-Meuthen, P. and Johannes, B. and Shushakov, V. and Grunewald, M. and Maassen, N. and Bühlmeier, Judith and Rittweger, J.}}, issn = {{1439-6319}}, journal = {{European Journal of Applied Physiology}}, keywords = {{Physiology (medical), Public Health, Environmental and Occupational Health, Orthopedics and Sports Medicine, General Medicine, Public Health, Environmental and Occupational Health, Physiology}}, number = {{4}}, pages = {{727--738}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Musculoskeletal effects of 5 days of bed rest with and without locomotion replacement training}}}, doi = {{10.1007/s00421-014-3045-0}}, volume = {{115}}, year = {{2014}}, } @article{33400, abstract = {{We examined, in immobilization, the effect of a diet high in sodium chloride (NaCl) on bone markers, nitrogen balance, and acid-base status. Eight healthy male test subjects participated in a 14-day head-down-tilt bed rest (HDBR) study. During the bed rest period they received, in a randomized crossover design, a high (7.7 meq Na+/kg body wt per day) and a low (0.7 meq Na+/kg body wt per day) NaCl diet. As expected, 24-h excretion of urinary calcium was significantly greater in the high-NaCl-intake HDBR phase than in the low-NaCl-intake HDBR phase ( P < 0.001). High NaCl intake caused a 43–50% greater excretion of the bone resorption markers COOH- (CTX) and NH2- (NTX) terminal telopeptide of type I collagen in HDBR than low NaCl in HDBR (CTX/NTX: P < 0.001). Serum concentrations of the bone formation markers bone-specific alkaline phosphatase (bAP) and NH2-terminal propeptide of type I procollagen (PINP) were identical in both NaCl intake phases. High NaCl intake led to a more negative nitrogen balance in HDBR ( P < 0.001). Changes were accompanied by increased serum chloride concentration ( P = 0.008), reduced blood bicarbonate ( P = 0.017), and base excess ( P = 0.009) whereas net acid excretion was lower during high than during low NaCl intake in immobilization ( P < 0.001). High NaCl intake during immobilization exacerbates disuse-induced bone and muscle loss by causing further protein wasting and an increase in bone resorption. Changes in the acid-base status, mainly caused by disturbances in electrolyte metabolism, seem to determine NaCl-induced degradation processes.}}, author = {{Frings-Meuthen, Petra and Bühlmeier, Judith and Baecker, Natalie and Stehle, Peter and Fimmers, Rolf and May, Francisca and Kluge, Goetz and Heer, Martina}}, issn = {{8750-7587}}, journal = {{Journal of Applied Physiology}}, keywords = {{Physiology (medical), Physiology}}, number = {{2}}, pages = {{537--542}}, publisher = {{American Physiological Society}}, title = {{{High sodium chloride intake exacerbates immobilization-induced bone resorption and protein losses}}}, doi = {{10.1152/japplphysiol.00454.2011}}, volume = {{111}}, year = {{2011}}, }