ABSTRACTIpavec, M, Grapar Žargi, T, Jelenc, J, and Kacin, A. Efficiency of pneumatic tourniquet cuff with asymmetric pressure distribution at rest and during isometric muscle action. J Strength Cond ...Res 33(9)2570–2578, 2019—The aim of this study was to compare effects of newly designed double-chamber cuff with asymmetric pressure (APC) distribution and standard single-chamber cuff with symmetric pressure (SPC) distribution on muscle perfusion and volitional activation. First, the 2 cuffs were compared bilaterally on resting thigh muscles of 17 healthy volunteers at 4 cuff pressures (120, 160, 200, and 240 mm Hg). Then, the subjects performed the isometric endurance test of knee extensor muscles to volitional failure at 40% of maximal volitional isometric action in both free-flow and blood flow restricted condition. Changes in hemoglobin kinetics in vastus lateralis muscle (near-infrared spectroscopy), surface electromyography of vastus medialis muscle, and pain intensity (visual analogue scale VAS) were continuously recorded. At rest, a significant difference (p = 0.009) in velocity of change in total hemoglobin concentration was noted between the cuffs at 160 mm Hg (APC = 0.028 μM·s and SPC = 0.056 μM·s). The VAS scores significantly increased (p = 0.031) at pressures ≥200 mm Hg, with no difference between the cuffs. Duration of isometric action with blood flow restriction was 12% shorter (p = 0.003) than in free-flow condition, with no difference between the cuffs. There were no significant differences in muscle activation or hemoglobin kinetics between the exercise conditions or cuff types. The results show that APC reduces blood flow in quadriceps femoris muscle at rest at lower pressure than SPC, which suggests its enhanced efficiency for blood flow restriction. Given that application of either type of cuff during sustained isometric action had only minor impact on muscle endurance and oxygen kinetics, future research must focus primarily on dynamic muscle actions.
The degree of quadriceps femoris muscle (QF) atrophy is recognized as one of the key factors of poor knee function and patient's outcome, despite successful reconstruction of anterior cruciate ...ligament (ACL).
The study assessed whether muscle preconditioning with ischemic exercise can attenuate loss of QF volume, strength, and function after ACL reconstruction.
Prospective, single-centre, quasi-randomized, controlled trial with sham intervention.
University Medical Centre and Laboratory of Physiotherapy Research.
Patients with total ACL rupture elected for reconstructive surgery.
Twenty subjects undergoing ACL reconstruction performed 5 exercise sessions during the last 10 days before surgery. They were assigned into two groups performing either low-load ischemic knee-extension exercise (ISHEMIC group), or standard knee-extension exercise (SHAM group). QF volume, maximal voluntary isometric contraction torque and single-leg anterior reach distance were assessed prior to preconditioning and at 4 and 12 weeks postsurgery.
There were no significant differences between the groups in any of the variables prior to, or after surgery. The deficit in QF vastii volume increased (P<0.001) to 20±5 % in ISCHEMIC and 23±10 % in SHAM group at 4 weeks and persisted (P<0.001) at 16±4 % in ISCHEMIC and 20±11 % in SHAM group at 12 weeks postsurgery. Deficit in QF maximal isometric torque persisted (P<0.05) at 15±15 % in ISCHEMIC and 22±16 % in SHAM group at 12 weeks postsurgery. There were no significant differences in single-leg anterior reach distance between the groups at any time point.
Short-term preconditioning with low-load ischemic exercise exhibited no different effect on QF muscle mass, isometric strength, or knee functional loss than comparable standard exercise in patients undergoing ACL reconstruction.
Preconditioning with ischemic exercise of five training sessions or shorter does not have any clinically important effect on preservation of quadriceps femoris muscle mass and function in patients after arthroscopic ACL reconstruction.
Background: Several studies showed that the addition of trunk muscle or core stability exercises in the sport training programs is an effective prevention of spinal and other musculoskeletal ...injuries.Methods: Twelve female basketball players performed supervised five-week exercise program focused on strengthening the trunk muscles. The program was performed three times per week during pre-season. Sorensen test, Fitnessgram Dynamic Curl-Up test, Prone Plank test and Side Bridge test were used to evaluate trunk muscles performance prior to and immediately after the exercise program completion and again after a three-month follow up period.Results: The results of Sorensen test and Prone Plank test significantly improved immediately after the program, but values returned to baseline at follow-up. In contrast, the results of Fitnessgram Dynamic Curl-Up test and Side Bridge test improved significantly with exercise program and remained significantly higher also at follow-up.Conclusions: Exercise program with emphasis on strengthening the trunk and core muscles can improve muscle performance, however, the results deteriorate shortly after program termination. In order to achieve long-term results, trunk and core muscle exercises have to be performed on regular basis, hence they must be incorporated into general strengthening programs of basketball players.
Background: Several studies showed that the addition of trunk muscle or core stability exercises in the sport training programs is an effective prevention of spinal and other musculoskeletal injuries. ...Methods: Twelve female basketball players performed supervised five-week exercise program focused on strengthening the trunk muscles. The program was performed three times per week during pre-season. Sorensen test, Fitnessgram Dynamic Curl-Up test, Prone Plank test and Side Bridge test were used to evaluate trunk muscles performance prior to and immediately after the exercise program completion and again after a three-month follow up period. Results: The results of Sorensen test and Prone Plank test significantly improved immediately after the program, but values returned to baseline at follow-up. In contrast, the results of Fitnessgram Dynamic Curl-Up test and Side Bridge test improved significantly with exercise program and remained significantly higher also at follow-up. Conclusions: Exercise program with emphasis on strengthening the trunk and core muscles can improve muscle performance, however, the results deteriorate shortly after program termination. In order to achieve long-term results, trunk and core muscle exercises have to be performed on regular basis, hence they must be incorporated into general strengthening programs of basketball players.
Introduction: It has been shown that sufficient amount of energy provided by electromagnetic diathermy induces the increase of skin temperature and underlying tissues. However, scarce information is ...available on the differences in responses initiated by various techniques of diathermy. The goal of the present study was to compare thermal and hemodynamic responses of the skin and underlying muscles of the forearm to diathermy applied with electric (EF) or magnetic field (MF). Methods: Eleven healthy volunteers participated in the study. On two separate occasions, they randomly received 20-minut diathermy with EF or with MF. Skin and tympanic temperature, and heart rate were measured. Further, kinetics of muscle oxyhemoglobin and deoxyhemoglobin kinetics were obtained. Thermal perception and thermal comfort were noted through the application of EF and MF. Results: The skin temperature increased similarly during the administration of EF and MF, by ~ 8.0 ± 1.3°C on both occasions. The thermal perception was more intense during the application of EF. Accordingly, the thermal comfort during the application of EF was perceived as less comfortable as compared with MF. During MF the increase in minute muscle blood flow and oxygen consumption was for ~ 42 % higher compared to the heating with EF. Conclusion: Although the increase in skin temperature was similar between EF and MF, the application of diathermy with MF was perceived more comfortable by the participants. Furthermore, the increase in minute muscle blood flow and oxygen consumption was higher in MF compared with EF. Thus, when muscle is the target tissue for physical therapy, a diathermy with magnetic field is the technique of choice.
Introduction: It has been shown that sufficient amount of energy provided by electromagnetic diathermy induces the increase of skin temperature and underlying tissues. However, scarce information is ...available on the differences in responses initiated by various techniques of diathermy. The goal of the present study was to compare thermal and hemodynamic responses of the skin and underlying muscles of the forearm to diathermy applied with electric (EF) or magnetic field (MF).
Methods: Eleven healthy volunteers participated in the study. On two separate occasions, they randomly received 20-minut diathermy with EF or with MF. Skin and tympanic temperature, and heart rate were measured. Further, kinetics of muscle oxyhemoglobin and deoxyhemoglobin kinetics were obtained. Thermal perception and thermal comfort were noted through the application of EF and MF.
Results: The skin temperature increased similarly during the administration of EF and MF, by ~ 8.0 ± 1.3°C on both occasions. The thermal perception was more intense during the application of EF. Accordingly, the thermal comfort during the application of EF was perceived as less comfortable as compared with MF. During MF the increase in minute muscle blood flow and oxygen consumption was for ~ 42 % higher compared to the heating with EF.
Conclusion: Although the increase in skin temperature was similar between EF and MF, the application of diathermy with MF was perceived more comfortable by the participants. Furthermore, the increase in minute muscle blood flow and oxygen consumption was higher in MF compared with EF. Thus, when muscle is the target tissue for physical therapy, a diathermy with magnetic field is the technique of choice.
Blood flow restricted resistance (BFRR) training with pneumatic tourniquet has been suggested as an alternative for conventional weight training due to the proven benefits for muscle strength and ...hypertrophy using relatively low resistance, hence reducing the mechanical stress across a joint. As such, it has become an important part of rehabilitation programs used in either injured or operated athletes. Despite a general consensus on effectiveness of BFRR training for muscle conditioning, there are several uncertainties regarding the interplay of various extrinsic and intrinsic factors on its safety and efficiency, which are being reviewed from a clinical perspective. Among extrinsic factors tourniquet cuff pressure, size and shape have been identified as key for safety and efficiency. Among intrinsic factors, limb anthropometrics, patient history and presence of cardiac, vascular, metabolic or peripheral neurologic conditions have been recognized as most important. Though there are a few potential safety concerns connected to BFRR training, the following have been identified as the most probable and health-hazardous: (a) mechanical injury to the skin, muscle, and peripheral nerves, (b) venous thrombosis due to vascular damage and disturbed hemodynamics and (c) augmented arterial blood pressure responses due to combined high body exertion and increased peripheral vascular resistance. Based on reviewed literature and authors’ personal experience with the use of BFRR training in injured athletes, some guidelines for its safe application are outlined. Also, a comprehensive risk assessment tool for screening of subjects prior to their inclusion in a BFRR training program is being introduced.
Blood flow restricted resistance (BFRR) training with pneumatic tourniquet has been suggested as an alternative for conventional weight training due to the proven benefits for muscle strength and ...hypertrophy using relatively low resistance, hence reducing the mechanical stress across a joint. As such, it has become an important part of rehabilitation programs used in either injured or operated athletes. Despite a general consensus on effectiveness of BFRR training for muscle conditioning, there are several uncertainties regarding the interplay of various extrinsic and intrinsic factors on its safety and efficiency, which are being reviewed from a clinical perspective. Among extrinsic factors tourniquet cuff pressure, size and shape have been identified as key for safety and efficiency. Among intrinsic factors, limb anthropometrics, patient history and presence of cardiac, vascular, metabolic or peripheral neurologic conditions have been recognized as most important. Though there are a few potential safety concerns connected to BFRR training, the following have been identified as the most probable and health-hazardous: (a) mechanical injury to the skin, muscle, and peripheral nerves, (b) venous thrombosis due to vascular damage and disturbed hemodynamics and (c) augmented arterial blood pressure responses due to combined high body exertion and increased peripheral vascular resistance. Based on reviewed literature and authors’ personal experience with the use of BFRR training in injured athletes, some guidelines for its safe application are outlined. Also, a comprehensive risk assessment tool for screening of subjects prior to their inclusion in a BFRR training program is being introduced.
Introduction: It has been shown that a sufcient amount of energy provided by electromagnetic diathermy induces an increase in skin temperature and underlying tissues. However, scarce information is ...available on the dierences in responses initiated by various techniques of diathermy. The goal of the present study was to compare thermal and hemodynamic responses of the skin and underlying muscles of the forearm to diathermy applied with electric (EF) or magnetic (MF) elds. Methods: Eleven healthy volunteers participated in the study. On two separate occasions, they randomly received 20-minute diathermy with EF or with MF. Skin and tympanic temperature, and heart rate were measured. Further, kinetics of muscle oxyhemoglobin and deoxyhemoglobin were obtained. Thermal perception and thermal comfort were noted during the application of EF and MF. Results: The skin temperature increased similarly during the administration of EF and MF, by ~ 8.0 (1.3) C on both occasions. The thermal perception was more intense during the application of EF. Accordingly, the thermal comfort during the application of EF was perceived as less comfortable in comparison with MF. During MF, the increase in minute muscle blood ow and oxygen consumption was by ~ 42 % higher compared to the heating with EF. Conclusion: Although the increase in skin temperature was similar between EF and MF, the application of diathermy with MF was perceived as more comfortable by the participants. Furthermore, the increase in minute muscle blood ow and oxygen consumption was higher in MF compared to EF. Thus, when muscle is the target tissue for physical therapy, a diathermy with magnetic eld is the technique of choice.
Uvod: Raziskave kažejo, da vadba za krepitev mišic trupa oz. stabilizacijska vadba lahko učinkovito preprečuje različne mišično-kostne poškodbe, zlasti hrbtenice. Metode dela: Dvanajst košarkaric je ...v času pripravljalnega obdobja trikrat na teden izvajalo dodatno, 5-tedensko vodeno vadbo z namenom krepiti mišice trupa. Učinki so bili ovrednoteni pred vadbo, takoj po zaključku programa in tri mesece po zaključeni vadbi s sledečimi testi: Sorensen test, dinamični test dviganja trupa Fitnessgram, test opore na podlakteh in test stranskega mostu. Rezultati: Pri Sorensenovem testu in testu opore na podlakteh se je zmogljivost mišic po vadbenem programu pomembno izboljšala in se po treh mesecih približala izhodiščnim vrednostim. Pri dinamičnem testu dviganja trupa Fitnessgram in testu stranskega mostu se je zmogljivost mišic trupa po vadbenem programu izboljšala in se ohranila tudi tri mesece po končanem programu. Zaključki: Vadbeni program s poudarkom na krepitvi mišic stabilizatorjev trupa lahko kratkoročno izboljša njihovo zmogljivost, vendar po prenehanju ciljanega programa zmogljivost mišic trupa upade kljub ohranjanju visoke ravni telesne dejavnosti. Za doseganje dolgoročnih rezultatov bi bilo potrebno redno izvajati stabilizacijsko vadbo, kar bi najlažje dosegli z vključitvijo vadbe v redni program krepitev mišic košarkaric.
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