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Objective To analyze the impact of soldiers’ single-leg landing with load carriage on knee joint, and investigate its relationship with muscle strength, so as to provide references for daily load carriage training. Methods A total of 12 soldiers were required to perform single-leg landing from the 30 cm height without load carriage and with 15 kg load carriage,respectively.The kinematic and kinetic parameters were collected using Vicon motion capture system and AMTI force platform. The surface electromyography (sEMG) of anterior and posterior thigh muscles were also collected simultaneously, and the isokinetic strength during knee flexion and extension was tested. Results Compared with landing without load carriage, knee flexion angle and joint reaction force significantly increased during landing with 15 kg load carriage (P0.05). There was a significant negative correlation between peak moment of knee extension and vertical ground reaction force during single-leg landing without load carriage (P0.05). Conclusions Knee flexion angle and joint reaction force significantly increase during single-leg landing with 15 kg load carriage, the activation of anterior and posterior thigh muscles can relieved the ground reaction force during landing, and muscle strength plays some role in preventing landing injury.
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Objective@#To compare the efficacy of intra-articular injection of autologous platelet-rich plasma (PRP) with that of sodium hyaluronate for patients with knee osteoarthritis (KOA).@*Methods@#Fifty KOA patients were randomly divided into a PRP group (n=25) and a sodium hyaluronate group (n=25). Those in the PRP group were injected intra-articularly with 5 ml of autologous PRP every 2 weeks for 6 consecutive weeks, while the sodium hyaluronate group was given intra-articular injections of 2 ml of sodium hyaluronate once a week for 6 weeks. Both groups performed isokinetic strength training three times a week for 6 weeks. Before as well as 6 weeks, 3 months, 6 months and 12 months after the treatment, both groups were followed and evaluated using the Western Ontario and McMaster University osteoarthritis index (WOMAC). A Biodex System 4 isometric muscle strength testing system was used to evaluate the knees′ peak torque (PT) in flexion and extension, total power (TW), and average power (AP).@*Results@#Before the treatment there were no significant differences in pain, stiffness or average WOMAC score between the two groups. Afterward significant improvement was observed in the pain, stiffness and WOMAC scores of both groups. Compared with the sodium hyaluronate group, significantly greater decreases in the average WOMAC pain score were observed in the PRP group after the different intervals. That was also true of the average stiffness scores and the overall average WOMAC scores after 6 and 12 months. The flexor and extensor PT, TW and AP at the angular velocities of 60°/s and 90°/s also improved significantly in both groups after 6 weeks and 12 months, with the improvement of the PRP group significantly greater than that in the control group at the same time points.@*Conclusion@#Intra-articular injection of either autologous PRP or sodium hyaluronate can effectively alleviate the clinical symptoms of KOA when combined with isokinetic strength training. However, PRP is the more effective. Its use is worthy of clinical application and promotion.
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Objective To compare the efficacy of intra-articular injection of autologous platelet-rich plasma (PRP) with that of sodium hyaluronate for patients with knee osteoarthritis (KOA). Methods Fifty KOA patients were randomly divided into a PRP group ( n=25) and a sodium hyaluronate group ( n=25) . Those in the PRP group were injected intra-articularly with 5 ml of autologous PRP every 2 weeks for 6 consecutive weeks, while the sodium hyaluronate group was given intra-articular injections of 2 ml of sodium hyaluronate once a week for 6 weeks. Both groups performed isokinetic strength training three times a week for 6 weeks. Before as well as 6 weeks, 3 months, 6 months and 12 months after the treatment, both groups were followed and evaluated using the Western Ontario and McMaster University osteoarthritis index ( WOMAC) . A Biodex System 4 isometric muscle strength testing system was used to evaluate the knees' peak torque (PT) in flexion and extension, total power (TW), and average power (AP). Results Before the treatment there were no significant differences in pain, stiffness or average WOMAC score be-tween the two groups. Afterward significant improvement was observed in the pain, stiffness and WOMAC scores of both groups. Compared with the sodium hyaluronate group, significantly greater decreases in the average WOMAC pain score were observed in the PRP group after the different intervals. That was also true of the average stiffness scores and the overall average WOMAC scores after 6 and 12 months. The flexor and extensor PT, TW and AP at the angular velocities of 60°/s and 90°/s also improved significantly in both groups after 6 weeks and 12 months, with the improvement of the PRP group significantly greater than that in the control group at the same time points. Conclu-sion Intra-articular injection of either autologous PRP or sodium hyaluronate can effectively alleviate the clinical symptoms of KOA when combined with isokinetic strength training. However, PRP is the more effective. Its use is worthy of clinical application and promotion.
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PURPOSE: The purpose of this study was to investigate the changes on alpine skiers' body composition, anaerobic power, isokinetic knee strength and muscle balance ratio (hamstring to quadriceps [HQ] ratio) before and after winter season. METHODS: The subjects of this study was 22 elite alpine skier, aged 16–20 years. Participants were divided into two groups (male, 12; female, 10). The study conducts a periodization training program in the winter season for 4 months. The data processing of this study was analyzed by paired t-test, using SPSS 21.0 statistics program. RESULTS: There was significance on fat free mass in male group (p < 0.05); there was significance on anaerobic power and average power in female group (p < 0.01), and fatigue index significantly increased in male group (p < 0.05). There was significance on extension power of male group and flexion power of female group in 30°/sec. There was significance on extension power of both groups in 180°/sec (p < 0.05). There was significant increase on flexion power of male group in 240°/sec (p < 0.01). There was significant increase on H/Q% of female right side in 30°/sec (p < 0.01). There was significance on right side of both groups in 180°/sec (p < 0.05). There were significances on right and left side of both groups in 240°/sec (male, p < 0.01; female, p < 0.05). CONCLUSION: Therefore, this study suggests that the periodization training should be important to maintain and to develop seasonal condition of alpine skiers.
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Female , Humans , Male , Body Composition , Education , Fatigue , Knee , SeasonsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the clinical efficacy of warm-needling moxibustion for knee osteoarthritis (KOA), and to explore its effects on isokinetic strength of lower limb muscle.</p><p><b>METHODS</b>Fifty cases of KOA were randomly divided into an observation group (25 cases) and a control group (21 cases), but 4 cases lost contact. The observation group was treated with warm-needling moxibustion at Dubi (ST 35), Neixiyan (EX-LE 4), Xuehai (SP 10), Liangqiu (ST 34), Yinlingquan (SP 9), Yanglingquan (GB 34), Weizhong (BL 40), Heyang (BL 55) and Fengshi (GB 31) for 40 min per treatment. The first 6 treatments were given once a day, and the last 6 treatments were given once every other day. 12 treatments were taken as one course, and totally 3-week treatment was given. No treatment was given in the control group for 3 weeks. The isokinetic strength of extensor muscle and flexor muscle, including the total work, absolute peak torque (aPT) and relative peak torque (rPT), and Western Ontario and McMaster Universities Arthritis Index (WOMAC), and comprehensive efficacy were observed and compared in the two groups.</p><p><b>RESULTS</b>Compared before treatment, the total work, aPT and rPT of the extensor and flexor muscle increased significantly after treatment in the observation group (<0.01,<0.05), but the flextion/extention ratio was lowered (<0.05). In the control group, aPT and rPT of flexor muscle were reduced after treatment (<0.05,<0.01). The total work, aPT and rPT of the extensor muscle in the observation group were higher than those in the control group after treatment (<0.05,<0.01), but the flextion/extention ratio was lowered (<0.05). The item score and total score of WOMAC were reduced in the observation group after treatment (all<0.01), but no significant change was observed in the control group (all>0.05). The pain score, stiffness scores and total score of WOMAC in the observation group were lower than those in the control group (<0.01,<0.05); the score of daily function activities was declined in the observation group, but not significantly different from that in the control group (>0.05). The total effective rate was 88.0% (22/25) in the observation group.</p><p><b>CONCLUSIONS</b>Warm-needling moxibustion could relieve pain, improve function and muscle balance, strengthen extensor and flexor muscle power, especially extensor, which has superior clinical efficacy.</p>
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Objective To study the effect of isokinetic strength training on upper limb motor function and activities of daily living (ADL) in stroke patients with hemiplegia. Methods From January to December, 2016, 56 stroke patients with hemiplegia were randomly di-vided into control group and observation group equally. Both groups received routine rehabilitation training, and the observation group ac-cepted hemiplegic limb flexor and extensor muscle isokinetic strength training in addition, for four weeks. They were assessed with Fugl-Meyer Assessment-upper limb (FMA-UL), modified Ashworth Scale (MAS), modified Barthel Index (MBI) and biomechanical index-es of elbow flexion and extension with Biodex System-4 before and after treatment. Results The scores of FMA and MBI improved after treatment (t>7.083, P2.369, P2.149, P2.027, P<0.05), except the peak torque at 60°/s angular velocity. Conclusion Isokinetic strength training can improve the motor function of upper limbs and activities of daily living in stroke patients with hemiplegia.
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This study concerns norm-referenced criteria for isokinetic strength of the lower limbs for the Korean high school baseball players. Two hundred one high school baseball players were participated in this study. They didn't have any medical problem at the lower limbs. Each test was conducted four times in the ankle plantar flexion/dorsiflexion test at 30°/sec speed, knee flexion/ extension test was conducted four times at 60°/sec speed. Humac Norm (CSMI, USA) system was used to obtained the value of peak torque, peak torque % body weight. The results were presented as a norm-referenced criterion value using 5-point scale of cajori, by 5 group (6.06%, 24.17%, 38.30%, 24.17%, and 6.06%) and a few suggestions from this study as follows. The provided criterion of peak torque and peak torque % body weight are very useful information for baseball palyers, baseball coach, athletic trainers and sports injury rehabilitation experts, to utilize as an objective clinical assessment data.
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Humans , Ankle , Athletic Injuries , Baseball , Body Weight , Knee , Lower Extremity , Rehabilitation , Sports , TorqueABSTRACT
BACKGROUND: It is not clear whether the pronator quadratus (PQ) muscle actually heals and provides a meaningful pronation force after volar plating for distal radius fractures (DRFs). We aimed to determine whether the length of the PQ muscle, which is dissected and then repaired during volar plating for a DRF, affects the forearm rotation strength and clinical outcomes. METHODS: We examined 41 patients who requested hardware removal after volar plating. We measured the isokinetic forearm rotation strength and clinical outcomes including grip strength, wrist range of motion, and disabilities of the arm, shoulder and hand (DASH) scores at 6 months after fracture fixation. During the hardware removal surgery, which was performed at an average of 9 months (range, 8.3 to 11.5 months) after fracture fixation, we measured the PQ muscle length. RESULTS: The average PQ muscle length was 68% of the normal muscle length, and no significant relationship was found between the PQ muscle length and the outcomes including isokinetic forearm rotation strength, grip strength, wrist range of motion, and DASH scores. CONCLUSIONS: This study demonstrates that the length of the healed PQ muscle does not affect isokinetic forearm rotation strength and clinical outcomes after volar plating for DRFs. The results of this study support our current practice of loose repair of the PQ that is performed by most of the surgeons to prevent tendon irritation over the plate, and suggest that tight repair of the PQ is not necessary for achieving improved forearm function.
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Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Bone Plates , Device Removal , Forearm/physiopathology , Fracture Fixation, Internal/methods , Hand Strength , Muscle Strength , Muscle, Skeletal/physiopathology , Radius Fractures/diagnostic imaging , Range of Motion, Articular , Wound HealingABSTRACT
Objective To observe any effects of using isokinetic strengthening exercises combined with intra-articular injection of sodium hyaluronate and joint mobilization in treating patients with knee osteoarthritis (KOA).Methods Eighty-one KOA patients were divided into a combined treatment group,a conventional treatment group and a control group.The combined treatment group received isokinetic strengthening training,intra-articular injections of sodium hyaluronate and joint mobilization therapy; the conventional treatment group received the injections and mobilization only; the control group was instructed to do ankle pumps at home on their own.Before the start of treatment and after 4 weeks,knee pain was self-assessed [using a visual analogue scale (VAS) for pain] along with knee range of motion (ROM),quality of life (using the WOMAC condensed health survey rating scale) and indexes of isokinetic strength [including the knee flexors,extensor peak torque (PT),and the flexion and extension angles corresponding peak torque (AOPT)] in both groups.Results After 4 weeks of treatment,statistically significant improvements compared to the baseline values were observed in both groups.The combined treatment group,however,improved to a significantly greater extent than the conventional treatment group in terms of all of the measures.Conclusion Isokinetic strength training combined with intra-articular injections of sodium hyaluronate and joint mobilization has a synergistic effect in enhancing knee stability and improving the performance in activities of daily life of KOA patients.
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The purpose of this study was to investigate of isokinetic strength of quadriceps and hamstring, hamstrings/quadriceps ration in elite sports athletes to provide the data for injury prevention, fitness level evaluation and training methodology. The subjects selected for this study were 104 elite sports athletes. They didn't have any medical problem. Isokinetic peak torque, flexor/extensor ratio at 60 deg/sec of the knee extension and flexion were measured using an cybex 770. The data were analyzed utilizing One way ANOVA. The level of statistical significance was set at p<.05. On the basis of the results analyzed in this study, conclusion were drawn as follow: 1. Dominant knee extension peak torque (Nm) were no significant differences in man but man elite athletes were higher than woman elite players in 60 deg/sec (p<.05). 2. Dominant knee extension peak torque (% body weight) of man elite athletes were higher than woman elite players in 60 deg/sec except only man volleyball athletes (p<.05). 3. Dominant knee flexion peak torque (Nm) were no significant differences in man but man elite athletes were higher than woman elite players in 60 deg/sec (p<.05). 4. Dominant knee flexion peak torque (% body weight) of man elite athletes were higher than woman elite players in 60 deg/sec (p<.05). 5. Knee flexion/extension peak torque ratio (H : Q) were no significant differences according to sex and proper H : Q ratio was 54~64%.
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Female , Humans , Anterior Cruciate Ligament , Athletes , Knee , Sports , Torque , VolleyballABSTRACT
OBJECTIVE: The purpose of this study is to evaluate concentric and eccentric trunk muscle strength in patients with chronic low back pain and compare it with healthy controls to determine the role of trunk muscle in chronic low back pain METHOD: Subjects were 20 chronic low back pain patients with the duration at least 6 months and 20 normal adults. Concentric and eccentric isokinetic trunk muscle test was performed at specific speeds (30degrees, 60degrees, 120degrees/sec) with Cybex 770 machine in back pain patients and healthy control. RESULTS: The strength of trunk flexor and extensor muscles of chronic low back pain patients was significantly weaker than that of normal controls. Eccentric peak torque was significantly higher than concentric peak torque in both patients and healthy control. A concentric and eccentric ratio of patients was lower than that of normal controls. The correlation between concentric and eccentric variables was high. Our results show that concentric peak torque has the highest correlation with eccentric peak torque. CONCLUSION: Isokinetic evaluations of the trunk muscle offer objective and quantitative data of patients with chronic low back pain and will be clinically useful in muscle power measurement of lumbar muscles.
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Adult , Humans , Back Pain , Low Back Pain , Muscle Strength , Muscles , TorqueABSTRACT
In this study, the effect of moderate endurance training on muscle morphological properties of human thigh muscles and isokinetic strength was examined. Five sedentary females carried out a training program of 30 min./day, 3 times a week for a ten-week period. The load requirement was set to 60% of maximal aerobic capacity (Vo<SUB>2</SUB>max) of the subjects. In the determination of muscle cross-sectional areas (CSAs) by MRI, longitudinal sections were first imaged, and ten axial images along the length of femur were taken before and after the endurance training. Muscle CSA and mus-cle volume of knee extensors (KE), flexors (KF), and adductors (AD) were calculated, using the ten axial images. Vo<SUB>2</SUB>max was significantly increased after endurance training (14.6%, p<0.01) . Muscle CSA in KE was significantly increased at the ten levels of femur length. There were also significant increases at seven levels of femur length after endurance training in KF (p<0.05, and 0.01) . Percentage increase of msucle CSA in KE and KF were 10.9 to 16.5% and 7.7 to 15.8%, respectively. Although the muscle volume of KE, KF, and AD was significantly increased, no change in fat volume was observed after endurance training. Isokinetic knee extension and flexion peak torque and peak torque per unit of muscle CSA at three angular velocities (30, 180, and 300 deg/sec) didn't show significant changes. These results suggest that muscle hypertrophy induced by moderate endurance training has no effect on muscle strength.
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In this study, the effect of moderate endurance training on muscle morphological properties of human thigh muscles and isokinetic strength was examined. Five sedentary females carried out a training program of 30 min./day, 3 times a week for a ten-week period. The load requirement was set to 60% of maximal aerobic capacity (Vo<SUB>2</SUB>max) of the subjects. In the determination of muscle cross-sectional areas (CSAs) by MRI, longitudinal sections were first imaged, and ten axial images along the length of femur were taken before and after the endurance training. Muscle CSA and mus-cle volume of knee extensors (KE), flexors (KF), and adductors (AD) were calculated, using the ten axial images. Vo<SUB>2</SUB>max was significantly increased after endurance training (14.6%, p<0.01) . Muscle CSA in KE was significantly increased at the ten levels of femur length. There were also significant increases at seven levels of femur length after endurance training in KF (p<0.05, and 0.01) . Percentage increase of msucle CSA in KE and KF were 10.9 to 16.5% and 7.7 to 15.8%, respectively. Although the muscle volume of KE, KF, and AD was significantly increased, no change in fat volume was observed after endurance training. Isokinetic knee extension and flexion peak torque and peak torque per unit of muscle CSA at three angular velocities (30, 180, and 300 deg/sec) didn't show significant changes. These results suggest that muscle hypertrophy induced by moderate endurance training has no effect on muscle strength.
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We investigated the muscle energetics using <SUP>31</SUP>P nuclear magnetic resonance (<SUP>31</SUP>P NMR) spectroscopy, muscle cross-sectional area by magnetic resonance imaging (MRI), isokinetic strength, maximal anaerobic power and 40-sec maximal cycling test (40 seconds power) in All Japan soccer players (JPN: n=6), Olympic and Youth representatives (OL: n=6), and Japan Soccer League players (JSL: n=5) . There was no significant difference in muscle energy metabolism measured by <SUP>31</SUP>P NMR between the JPN and the OL or JSL players at rest, during exercise, or in the recovery period. The total muscle cross-sectional area was significantly larger in the JPN players than in the OL players at the upper (70%) and the middle (50%) parts of the thigh (p<0.05) and than in the JSL players in the upper (p<0.01), middle (p< 0.05), and lower (30%) parts (p<0.01) . The isokinetic strength in left leg extension at 180 deg/sec was significantly greater in the JPN players than in the OL players (p<0.05) . Muscle strength was also greater in extension of both legs at 450 deg/sec (left p<0.05, right p<0.01) in the JPN players than in the JSL players. The maximum anaerobic power was significantly greater in the JPN players than in the OL players (p<0.05) and the JSL players (p<0.05), and the anaerobic power per kilogram of body weight was significantly higher in the JPN players than in the JSL players (p<0.01) . There was no significant difference in the 40 seconds power among the three groups. These results suggest that the JPN players have greater muscle power than the OL or JSL players because of the differences in the muscle mass.
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To investigate the relationship between maximal aerobic power (VO<SUB>2</SUB>max) and fatigu-abililty during repeated isokinetic contractions, 39 male speed skaters (mean 20.8 years) served as subjects. They were divided into two groups according to their VO<SUB>2</SUB>max levels ; high VO<SUB>2</SUB>max group (HI, n=19) and low VO<SUB>2</SUB>max group (LO, n=20) . VO<SUB>2</SUB>max was measured in all subjects during incremental exercise on a bicycle ergometer and body composition was determined by densitometry. Cross-sectional area (CSA) of the leg extensor muscles was evaluated using ultrasonic method. Fatiguability was assessed during the fatigue test consisting of 50 repeated isokinetic knee-extensions at an angular velocity of 180 deg⋅sec<SUP>-1</SUP>. Remark-able findings include :<BR>1. There were no significant differences in body composition and thigh composition between the two groups except for high subcutaneous fat in group LO.<BR>2. There were significant differences in VO<SUB>2</SUB>max between group HI (3.93<I>l</I>⋅min<SUP>-1</SUP>, 67.3 m<I>l</I>⋅kg LBM<SUP>-1</SUP>⋅min<SUP>-1</SUP>) and group LO (3.59<I>l</I>⋅min<SUP>-1</SUP>, 59.9 m<I>l</I>⋅kg LBM<SUP>-1</SUP>⋅min<SUP>-1</SUP>) .<BR>3. In the fatigue test, the average initial values did not differ, however, the average final values were higher in group HI. Also, a significant difference was observed in per unit CSA between the two groups.<BR>4. Higher peak forces (kg) in group HI were observed after the initial 30 dymanic contractions per unit CSA and % of peak values (% peak force) .<BR>5. A close relationship was demonstrated between VO<SUB>2</SUB>max per LBM and the fatigue index, i. e., the mean decline in peak force with 50 contractions (r=-0.37, p<0.05) .<BR>Based on the present findings it is suggested that maximal aerobic power (VO<SUB>2</SUB>max) influences the rate of fatigue development even during short-term maximal isokinetic contractions, and that there may be some physiological cross-linkages between cardiopulmonary regulation and the metabolic properties of skeletal muscles. This finding is also in conformity with earlier results indicating the importance of oxygen delivery as a limiting factor for muscle performance.