Improve Quadriceps Strength Research Articles

The Effect of Resistance Strength Training on Muscle Cross Education: A Meta analysis

Introduction: At present, a large number of studies have found that the phenomenon of cross transfer has achieved significant research results in sports training, rehabilitation therapy, and influencing mechanisms. Cross training refers to increasing muscle strength on the training side, while there is also a significant increase in muscle strength on the untrained homologous side. The main purpose of this review is to explore the impact mechanism of cross transfer phenomenon and summarize the optimal training methods and rehabilitation methods for cross transfer phenomenon. Aim of the study: Using meta-analysis method to systematically evaluate the effects of cross training (also known as cross education) on upper and lower limb muscle strength in different age groups and compare the training results. Material and methods: The system searched databases such as Wanfang Digital Resource Database, China National Knowledge Infrastructure Database, EBSCOhost, PubMed, Web of Science, and Cochrane Library from the default start time to December 2024. Two evaluators independently screened research literature on resistance strength training improving upper and lower limb muscle strength and hypertrophy in various age groups based on inclusion and exclusion criteria. Revmen 5.3 was used to evaluate all included literature and analyze their data. Result: 1)After 4 rounds of exclusion, 7 articles were finally included with a total sample size of 257 people; 2) Cross education intervention under resistance strength training can significantly enhance the strength of the quadriceps muscle in adults, with better results than the control group. The combined effect size is SMD=8.03, 95% CI:- 1.32，17.37， P＜0.01， 3) The degree to which cross education intervention enhances the strength of the gastrocnemius and wrist extensor muscles under resistance strength training is similar. The combined effect quantities are: SMD＝0.17，95% CI：-2.28，2.62，P≥0.01； SMD＝-0.39，95% CI：-3.02，2.25，P≥0.01； SMD=0.20, 95% CI: -0.81, 1.21, P ≥ 0.01 Conclusion: Cross education intervention under resistance strength training can significantly improve quadriceps strength and promote muscle hypertrophy in adults; The effect of cross education intervention under resistance force on promoting the strength and hypertrophy of the gastrocnemius muscle and wrist extensor muscle is similar.

The effect of neuromuscular electrical stimulation superimposed on quadriceps training on gait dynamics after anterior cruciate ligament reconstruction

Background Abnormal gait dynamics are an important risk factor responsible for the high incidence of traumatic knee osteoarthritis in patients undergoing anterior cruciate ligament (ACL) reconstruction. Objective To evaluate the effect of neuromuscular electrical stimulation (NMES) superimposed quadriceps training on gait dynamics. Methods A total of 32 postoperative patients were randomly allocated to the NMES and conventional training (CT) groups, with 16 patients per group. Patients in the CT group received the standardized conventional training for 60 min per day, 3 days per week for 6 weeks, while those in the NMES group received the same conventional training, but with NMES superimposed on the conventional open chain training of the quadriceps. The amount of time for training was equal between the two groups. Patients were evaluated at 8 and 14 weeks after surgery. The outcome measurements were maximum voluntary isometric contraction (MVIC) of the quadriceps used to assess the quadriceps strength, Lysholm score used to assess knee function and peak vertical ground reaction force (PvGRF), heel medial (HM) peak pressure and heel lateral (HL) peak pressure used to assess gait dynamics. Results Compared to the CT group, the NMES group had greater improvements in quadriceps strength (p<0.001, effect size = 2.93), knee function (p = 0.049, effect size = 2.06), and gait loading (including HL peak pressure (P = 0.007, effect size = 0.89) and PvGRF (P = 0.019, effect size = 0.62)). After the intervention, participants in both groups had a significantly lower rearfoot impulse and significantly higher forefoot impulse. Conclusions The NMES superimposed on conventional quadriceps open chain training has shown additional improvements in gait loading in patients after ACL reconstruction, which suggests it may contribute to delaying the onset of early postoperative traumatic knee osteoarthritis. In addition, changes in foot impulse may suggest a progressive trend in quadriceps avoidance gait in the early postoperative period.

Intraoperative tranexamic acid reduces postoperative haemarthrosis and improves early functional outcomes in double-bundle anterior cruciate ligament reconstruction.

Double-bundle anterior cruciate ligament reconstruction (ACLR) has biomechanical advantages but is associated with increased intraoperative bleeding. The role of tranexamic acid (TXA) in reducing postoperative joint haemarthrosis and improving the short-term outcomes of double-bundle ACLR has not yet been thoroughly investigated. This study aimed to assess the effects of intraoperative TXA on postoperative joint haemarthrosis and short-term functional outcomes in patients who underwent double-bundle ACLR. This retrospective cohort study included 80 male patients who underwent double-bundle ACLR between January 2019 and December 2022. The patients were divided into two groups: those who received TXA and those that did not. The TXA group received 50mL of TXA (10mg/mL) intravenously approximately 10min before tourniquet release, followed by an intra-articular injection of 50mL TXA (10mg/mL) immediately after wound closure, prior to tourniquet release, whereas the control group did not receive TXA. Primary outcomes included postoperative haemarthrosis volume, assessed using Coupens and Yate (CY) values; and short-term functional recovery, evaluated using range of motion (ROM), quadriceps strength, and visual analogue scale (VAS) pain scores on day 1, day 15, week 6, and week 12 postoperatively. Intraoperative administration of TXA in patients undergoing double-bundle ACLR reduced postoperative haemarthrosis, as measured by a lower CY value on postoperative day 1 (P=0.004) and day 15 (P<0.001). Compared to patients in the control group, patients in the TXA group reported lower VAS pain scores on day 1 (P<0.001), day 15 (P<0.001), and week 6 (P=0.028), together with improved quadriceps strength (P=0.043, day 1; P=0.009, day 15) and ROM (P<0.001, 12 weeks postoperatively) during the early postoperative period. The use of TXA during double-bundle ACLR may reduce postoperative joint haemarthrosis and enhance short-term functional outcomes.

Functional Outcome in Obese Patients Undergoing Image-Based Cruciate Retaining Robotic-Assisted Total Knee Arthroplasty Using the Subvastus Approach: A Short-Term Study.

Introduction Knee osteoarthritis (OA) is a prevalent degenerative joint disease that significantly affects quality of life, especially among obese and morbidly obese individuals. Total knee arthroplasty (TKA) is an effective treatment for end-stage OA, but it presents unique challenges in obese patients. The mini-subvastus approach (SA) and robotic-assisted TKA (RA-TKA) are emerging techniques that may address these challenges. This study evaluates the clinical and radiological outcomes of cruciate-retaining (CR) RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. Methods This study included 114 obese patients (215 knees) with primary OA who underwent CR RA-TKA (Maxx Meril CR knee, USA) using the Cuvis Joint® robotic system. Patients had a BMI of ≥30 kg/m² (n=101) and morbid obesity with a BMI ≥40 kg/m² (n=13). Preoperative planning involved CT scans and the J-planner for optimal implant size and positioning. Surgery was performed without tourniquets, and patients were mobilized postoperatively. Clinical outcomes were assessed using visual analog scale (VAS) scores and the American Knee Society Score (AKSS) at three and six months. Results The study included 85 females and 29 males with an average age of 61.8 years. Satisfactory knee exposure was achieved in all cases using SA, with no major complications such as wound infections, deep vein thrombosis, or component misalignment. Intraoperative challenges were managed effectively, including two cases of medial collateral ligament avulsion and one partial patellar tendon avulsion. Postoperative VAS scores showed significant pain reduction from pre-op (6.54) to post-op day 3 (1.3). AKSS improved from a pre-op average of 33.9 to 70.7 at three months and 80.9 at six months. Most patients (80%) achieved exceptional range of motion (ROM) ≥120° at six months. Discussion The mini-subvastus approach in RA-TKA offers several advantages, including reduced postoperative pain, faster recovery, and improved quadriceps strength, even in obese patients. The use of robotic assistance ensures accurate component positioning and alignment, mitigating the challenges typically associated with obese patients undergoing TKA. Conclusion The study demonstrates the feasibility and effectiveness of CR RA-TKA using the mini-subvastus approach in obese and morbidly obese patients. This technique provides adequate exposure, reduces pain, and promotes early mobilization and recovery with satisfactory clinical and radiological outcomes. The findings support the potential for wider adoption of this approach in managing knee OA in obese populations, though further studies with longer follow-up are warranted.

Operative Management of Pediatric Physeal Bar Development and Genu Valgum.

Pediatric orthopedic conditions present unique challenges due to ongoing skeletal growth and development. Managing these cases requires addressing both structural anomalies and functional deficits. This case report discusses a 13-year-old male with recurrent left knee pain exacerbated by physical activity. The patient's history of a left knee infection at 1.5 years of age, possibly septic arthritis or osteomyelitis, underscores the long-term consequences of early pathology on skeletal growth and alignment. Imaging studies revealed a distal lateral femur physis bar and genu valgum, necessitating surgical intervention. The surgery involved medial distal femur hemiepiphysiodesis and lateral distal femur bar excision to correct anatomical deformities and restore optimal limb alignment and function. Postoperative rehabilitation, including targeted exercises to improve quadriceps strength, was crucial for functional recovery and reducing the risk of complications such as medial patellofemoral pain. This case highlights the importance of a multidisciplinary approach in managing complex pediatric orthopedic cases.

Evaluating the Efficacy of Kinesthesia, Balance, and Vestibulo-Postural Training in Knee Osteoarthritis Management

Background: Knee osteoarthritis (OA) is a common degenerative joint disease that causes pain, reduced mobility, and impaired quality of life. This study compares the efficacy of kinesthesia and balance exercises with isometric strengthening versus vestibulo-postural training using a bipodalic stabilometric platform with isometric strengthening in improving muscle strength and functional independence in knee OA patients. Methods: Thirty subjects with knee OA, aged between 30-60 years, were randomly assigned to two groups. Group 1 (n=15) received kinesthesia and balance exercises along with isometric strengthening exercises, while Group 2 (n=15) received vestibulo-postural training using a bipodalic stabilometric platform combined with isometric strengthening exercises. Both groups performed their respective exercise regimens three times a week for four weeks. Outcomes measured included quadriceps and hamstrings strength using the Manual Muscle Testing (MMT) grading system and functional independence using the Barthel Index score. Results: Group 2 demonstrated significantly greater improvements in quadriceps strength (mean change: 1.34 vs. 0.40; p &lt; 0.001), hamstrings strength (mean change: 1.07 vs. 0.20; p &lt; 0.001), and Barthel Index score (mean change: 20.54 vs. 5.5; p &lt; 0.001) compared to Group 1. The between-group analysis confirmed that vestibulo-postural training with isometric strengthening was significantly more effective in enhancing muscle strength and functional independence in knee OA patients. Conclusion: Vestibulo-postural training using a bipodalic stabilometric platform combined with isometric strengthening exercises significantly improves muscle strength and functional independence in knee OA patients compared to kinesthesia and balance exercises with isometric strengthening. These findings highlight the importance of incorporating dynamic and challenging balance exercises into OA management strategies to optimize patient outcomes and enhance quality of life..

Eccentric Muscle Strengthening Using Maximal Contractions Is Deleterious in Knee Osteoarthritis: A Randomized Clinical Trial.

Objectives: To show the superiority of eccentric versus concentric strengthening in terms of improving quadriceps strength in knee osteoarthritis (OA), a randomized controlled study was conducted to perform 12 sessions of either eccentric or concentric isokinetic muscle strengthening over 6 weeks. Methods: We recruited males and females, aged between 40 and 70 years, with predominantly unilateral femorotibial OA. Exclusion criteria were having a prosthesis, inflammatory arthritis or flare-up of OA, symptomatic patellofemoral OA, cardiovascular or pulmonary disease that could be a contraindication to the study treatment, and any pathology that could cause muscle weakness. The primary endpoint was the between-group difference in change in maximum concentric isokinetic knee extension peak torque (PT) at 60°/s on the OA side at 6 weeks. Secondary endpoints were between-group difference in change in concentric hamstring PT at 60°/s; eccentric quadriceps and hamstring PT at 30°/s; 10 m and 200 m walking speeds; pain and functional status (WOMAC score) at 6 weeks and 6 months. Results: The sample consisted of 11 females and 27 males, with a mean age of 57.7 ± 7.52 years and a body mass index (BMI) of 25.95 ± 3.93 kg/m2. Quadriceps strength increased more at 6 weeks in the concentric than the eccentric group with no statistical difference. There was a rate of 25% major adverse events in the eccentric group. Conclusions: Eccentric training resulted in a smaller improvement in quadriceps strength than concentric training and was associated with a high risk of muscle injury, particularly to the hamstring muscles.

Effect of open vs. closed kinetic chain exercises in ACL rehabilitation on knee joint pain, laxity, extensor muscles strength, and function: a systematic review with meta-analysis.

PROSPERO [CRD42023475230].

Vitamin D as an intervention for improving quadriceps muscle strength in patients after anterior cruciate ligament reconstruction: study protocol for a randomized double-blinded, placebo-controlled clinical trial

BackgroundThe goal of anterior cruciate ligament reconstruction (ACLR) is to restore the preinjury level of knee function to return to play (RTP). However, even after completing the rehabilitation programme, some patients may have persistent quadriceps muscle weakness affecting knee function which ultimately leads to a failure in returning to play. Vitamin D has been long recognized for its musculoskeletal effects. Vitamin D deficiency may impair muscle strength recovery after ACLR. Correcting vitamin D levels may improve muscle strength.MethodsThis is a double-blinded, randomized controlled trial to investigate the effects of vitamin D supplementation during the post-operative period on quadriceps muscle strength in anterior cruciate ligament (ACL)-injured patients. Patients aged 18–50 with serum vitamin D < 20 ng/ml, unilateral ACL injury, > 90% deficit in total quadriceps muscle volume on the involved leg compared with uninvolved leg, Tegner score 7 + , and no previous knee injury/surgery will be recruited. To assess patient improvement, we will perform isokinetic and isometric muscle assessments, ultrasound imaging for quadriceps thickness, self-reported outcomes, KT-1000 for knee laxity, biomechanical analysis, and Xtreme CT for bone mineral density. To investigate the effect of vitamin D status on quadriceps strength, blood serum samples will be taken before and after intervention.DiscussionPatients with low vitamin D levels had greater quadriceps fibre cross-sectional area loss and impaired muscle strength recovery after ACL. The proposed study will provide scientific support for using vitamin D supplementation to improve quadriceps strength recovery after ACLR.Trial registrationClinicalTrials.gov NCT05174611. Registered on 28 November 2021.

Revision Patellar Tendon Reconstruction Using Hamstring Tendon Autograft

Background: Patellar tendon ruptures presenting in a chronic setting are rare events that impose technical surgical challenges due to proximal retraction of the patella, quadriceps muscle atrophy and contracture, and peripatellar adhesions. Various reconstruction techniques have been described using different grafts and fixation methods; however, there is a paucity of reported outcomes and there is no consensus on standard of care. Indications: The patient is a 36-year-old man who presented with a failed patellar tendon reconstruction 14 months after his initial surgery (performed 1 year after the initial injury) with functional weakness and loss of extension. The patient was indicated for a revision patellar tendon reconstruction due to persistent functional limitations. Technique Description: The revision patellar tendon reconstruction was performed with gracilis and semitendinosus tendon autografts harvested from the ipsilateral limb. Hardware was removed from the initial graft tunnels in the tibial tubercle and patella. Patellar height was estimated using fluoroscopic measurement of the contralateral patellar tendon length. The graft is first passed through the patellar tunnel, and the individual limbs of the graft are then both placed through the tibial tubercle tunnel. A sternal wire in a figure-of-eight configuration was used to progressively distalize the patella to match the native patellar height, and the graft was then tensioned and secured together. Results: The patient regained full range of motion at 2-year follow-up and was able to return to work and activities without functional limitations. Recent case series also using ipsilateral hamstring tendon autograft for chronic patellar tendon reconstruction report improved patient outcome scores, normal Insall-Salvati index, improved quadriceps strength, and high levels of patient satisfaction. Discussion/Conclusion: Chronic patellar tendon ruptures are technically challenging to treat, especially in the context of revision of a failed reconstruction. The technique presented in this video may aid orthopaedic surgeons in treating this rare but debilitating injury. Given the lack of high-quality evidence, future studies are needed to explore graft choices, graft fixation techniques, and postoperative protocols. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Can photobiomodulation improve quadriceps strength and endurance outcomes in asymptomatic adults? A double-blind randomized controlled trial

AimTo explore the effect of photobiomodulation on quadriceps strength and endurance torques in asymptomatic adults. MethodsTwenty-eight asymptomatic adults were randomized to one of two interventions: photobiomodulation (n = 14) or sham (n = 14). Quadriceps strength was evaluated by maximum voluntary isometric contraction test (60°) and endurance by an elastic resistance in multiple-set knee extension/flexion repetitions using a traction dynamometer. The outcomes were measured at three time points: pre-baseline; baseline and; final assessment. The photobiomodulation was applied to the quadriceps and triceps surae muscles of each participant's dominant lower limb, using a cluster with 1 infrared laser diode and 3 led amber of 170 mW for 240 s over four consecutive days. The sham group went through the same procedures, but the equipment was off, and patients and assessors were blinded to the intervention. Reliability and minimal detectable change of the measures were obtained from the pre-baseline and baseline time points. Differences between interventions were tested by an analysis of covariance. Results and discussionThere was no difference between photobiomodulation compared to sham in maximum isometric torque (mean difference (95% CI) = 0.008 (−0.29 to 0.31) and endurance torques (mean difference (95% CI) = 0.04 (−0.03 to 0.12). The mean difference was lower than the minimal detectable change for the maximum isometric torque (1.02 Nm.kg−1) and endurance torque (0.49 Nm.kg−1). ConclusionPhotobiomodulation does not improve quadriceps strength and endurance outcomes in asymptomatic adults.

Effects of core exercises on knee pain, disability, proprioception, and quadriceps strength in patients with knee osteoarthritis: A randomized controlled trial

Aim. This pretest-posttest controlled study investigated the effects of core exercises on knee pain, disability, proprioception, and quadriceps strength in patients with knee osteoarthritis (KOA). Materials and Methods. Eighty patients aged from 40-65 years with mild to moderate KOA were recruited from Cairo University hospitals. They were randomly assigned into two equal groups; group A received core exercises plus conventional exercises and group B received conventional exercises only. Sessions were done 3 times weekly for 4 weeks. Patients were evaluated, pre-and post-treatment, for knee pain (using visual analogue scale), disability (using aggregate locomotor function), proprioception (using inclinometer), and quadriceps strength (using dynamometer). Results. There were no significant differences between groups post-treatment (p-value &gt; 0.05). There was a significant improvement in quadriceps strength in group (A&amp;B) and pain and disability in group (A) post-treatment (p-value &lt; 0.05). Conclusions. Adding core exercises to conventional exercises showed a trend towards significance in reducing pain and disability than conventional exercises alone in KOA. On the other hand, conventional exercises with or without core exercises improved quadriceps strength rather than proprioception. Hence, further studies on a larger sample are promising.

Who's Afraid of Electrical Stimulation? Let's Revisit the Application of NMES at the Knee.

BACKGROUND: Restoring quadriceps strength is essential for successful rehabilitation of knee injuries, but many athletes return to their previous activity with persisting muscle weakness. Strong evidence supports using neuromuscular electrical stimulation (NMES) to improve quadriceps strength; however, there is a lack of widespread clinical implementation. We believe there is a critical need to provide clinical approaches that promote using NMES to improve patients' quadriceps strength and ensuring clinicians provide high-value rehabilitation care. CLINICAL QUESTION: What is best practice when using NMES to facilitate strength after injury, what are barriers to its use, and how can they be addressed? KEY RESULTS: We discuss the low clinical implementation of NMES, perceived barriers to using NMES, and provide recommendations for setup and dosage parameters for effective use of NMES. CLINICAL APPLICATION: We aim for this commentary, with accompanying videos, to serve as a resource for clinicians who are using commercially available NMES units in clinical practice. J Orthop Sports Phys Ther 2024;54(2):1-6. Epub 31 October 2023. doi:10.2519/jospt.2023.12028.

Acute effect of different doses of caffeinated chewing gum on exercise performance in caffeine-habituated male soccer players.

The ergogenic benefits of caffeine have been well established, but there is scarce research on its chewing gum form. The present research aimed to examine the effects of different doses (100 and 200 mg) of caffeinated chewing gum on muscle strength, vertical jump performance, and ball-kicking speed in trained male soccer players. In a double-blind, randomized counterbalanced, and crossover research design, 14 male soccer players (age = 22 ± 2 y; body mass = 74.2 ± 7.1 kg; height = 180.0 ± 6.8 cm; habitual caffeine intake = 358.9 ± 292.4 mg/day) participated in three experimental trials. In each trial, participants performed isometric handgrip strength, quadriceps and hamstring strength, ball-kicking speed, and 15 s countermovement jump test 10 min after chewing 100 mg (LCAF) or 200 mg (MCAF) of caffeinated gum or placebo (PLA). MCAF improved quadriceps strength (53.77 ± 5.77 kg) compared to LCAF (49.62 ± 8.81 kg, p = 0.048) and PLA (49.20 ± 7.20 kg, p = 0.032). However, neither LCAF nor MCAF had a significant effect on the isometric handgrip and hamstring strength, ball-kicking speed, and 15 s countermovement jump test (all p > 0.05). These findings support chewing gum as an alternative mode of caffeine administration which can be used as a nutritional ergogenic aid for trained soccer players, at least for quadriceps strength.

Combining age, sex, body mass index, sport level, and preoperative quadriceps strength improves the predictive ability of quadriceps strength recovery after anterior cruciate ligament reconstruction

PurposeThis study compared the predictive ability of each independent predictor with that of a combination of predictors for quadriceps strength recovery one year after anterior cruciate ligament (ACL) reconstruction.MethodsPatients who underwent primary ACL reconstruction using hamstring autografts were enrolled. Quadriceps strength, hamstring strength, and anterior tibial translation were measured, and the limb symmetry index (LSI) of the quadriceps and the hamstrings was calculated preoperatively and one year after surgery. Patients were classified into two groups according to the LSI of the quadriceps strength at one year postoperatively (≥ 80% or < 80%). Multivariate logistic regression analysis identified the independent predictors of quadriceps strength recovery, and the cut-off value was calculated using the receiver operating characteristic curve. A model assessing predictive ability of the combination of independent predictors was created, and the area under the curve (AUC) for each independent predictor was calculated by using the receiver-operating characteristic curves and the DeLong method.ResultsOf the 646 patients, 414 (64.1%) had an LSI of at least 80% for quadriceps strength one year after surgery, and 232 patients (35.9%) had an LSI of < 80%. Age, sex, body mass index (BMI), preinjury sport level, and LSI of preoperative quadriceps strength were independently associated with quadriceps strength recovery one year after ACL reconstruction. The cut-off values were age: 22.5 years; sex: female; BMI: 24.3 kg/m2; preinjury sport level: no sport; and LSI of preoperative quadriceps strength: 63.3%. The AUC of the model assessing the predictive ability of the combination of age, sex, BMI, preinjury sport level, and LSI of preoperative quadriceps strength was significantly higher (0.73) than that of similar factors of preoperative quadriceps strength (AUC: 0.63, 0.53, 0.56, 0.61, and 0.68, p < 0.01, respectively).ConclusionThe combination of age, sex, BMI, preinjury sport level, and LSI of preoperative quadriceps strength had a superior predictive ability for quadriceps strength recovery at one year after ACL reconstruction than these predictors alone. Multiple factors, including patient characteristics and preoperative quadriceps strength, should be considered when planning rehabilitation programs to improve quadriceps strength recovery after ACL reconstruction.Level of evidenceIII.

Feasibility and effect of 3/7 strength training method in cardiac rehabilitation: preliminary results

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Erasmus Hospital. Background Cardiovascular rehabilitation (CR) is a type 1A intervention for cardiovascular disease. Among the various exercise modalities, resistance training (RT) is recommended for improving cardiorespiratory fitness (volume of oxygen consumption [VO2] peak). However, different modalities of RT coexist and which modalities should be preferred is still a matter of discussion. A RT method, called 3/7, allowed in healthy young subject greater strength gains with a shorter training time. However, the feasibility, the safety and its effects have never been studied in CR. Purpose The aim was to assess the feasibility, safety and efficiency of the 3/7 method in CR to improve VO2 peak. Methods In this single center randomized clinical trial, participants underwent 12 weeks of supervised training. Intervention: Group 3/7 consisting of 5 incremental sets of 3 to 7 repetitions with 15 s of inter-set intervals of RT on leg press; leg extension, leg curl, triceps press machines. Group 3X9 (usual care) of 3 sets of 9 repetitions with 1 min of inter set intervals on the same machine and at the same intensity (70% of 1RM). Patients completed 3 sessions per week; endurance training is the same in both groups. The primary outcome was a change in VO2 peak during the cardiopulmonary exercise test from baseline to 12 weeks. Secondary outcomes were isokinetic leg strength at 60°/sec and feasibility. Results Between 2019 and 2022 101 patients (92 male) were enrolled and randomized to 3/7 (n=49) or 3x9 RT (n=52). The mean age was 62y±8 (range 34 – 85). A total of 65 participants completed testing at 12 weeks for the primary outcome, including 32 in the 3/7 group and 33 in the 3X9 group. There were similar improvements from baseline between groups, VO2 peak by 19% in 3/7 group with 17% in the 3X9 group (mean [SD] oxygen uptake: 3/7, 3.6 [4.1] mL/kg/min; 3X9, 3.3 [4.5] mL/kg/min; P = .4). 3/7 improved quadriceps strength by 12% compared with 11% in the 3X9 group (mean [SD] isokinetic leg strength: 3/7, 23 [21] N/m; 3X9, 10 [22] N/m; P = .01). We had more dropouts in the usual care group compared to the 3/7 group (19 vs 17). 3/7 group had high feasibility scores and low rates of withdrawal due to serious adverse events (1). Most dropouts were due to other conditions (Lost of follow-up [n=11], COVID-19 [n=6], other medical problems [n=6], returns to work [n=5], withdrew [n=4]). Conclusion(s) In this randomized clinical trial, a 12-week RT of the 3/7 method coupled with endurance training improved VO2 peak to the same level than the usual care in cardiac rehabilitation, but more leg strength was observed. The 3/7 method may reduce the number of dropouts compared to usual RT program because the time training is reduced for the same volume of work. Implications: These findings support inclusion of 3/7 method in cardiac rehabilitation programs as an adjunct or alternative modality to usual care.

The Effects of Testosterone and Transcutaneous Muscle Stimulation on Strength and Muscle Mass in Myotonic Dystrophy

In myotonic dystrophy type 1 (DM1) quadriceps weakness often results in severe functional limitations and genu recurvatum. To improve quadriceps strength the effects of isometric tetanic contractions using transcutaneous muscle stimulation (TMS) and testosterone enanthate (TE) were assessed. Ten DM1 subjects underwent unilateral TMS 6 hours per day for 14 days. The stimulated leg was randomly assigned and sham stimulation was done on the opposite leg by transcutaneous nerve stimulation. Muscle mass was estimated by cross-sectional area computed tomography and strength was measured by Cybex ergometry. Following the initial TMS period, 8 of 10 subjects were given a 12-week course of TE (3 mg/kg/wk) followed by 14 days of TMS. Neither TMS nor TE improved strength. Following 12 weeks of TE, there was an average increase in muscle mass of at least 8.7 +/- 1.6 cm2. These findings are consistent with the TE—increased muscle mass in DM1 as measured by creatinine clearance and total body potassium. The dissociation of mass and strength following TE and the failure of exercise to improve strength may have significance in characterizing the muscle defect in DM1.

Effect of Neuromuscular Exercises on Pain, Quadriceps Strength and Physical Function among Patients with Unilateral Knee Osteoarthritis. -a Single Group Reversal Design

Background: Osteoarthritis is a progressive disease of the synovial joint. The structural damage results in collapse of the cartilage and subchondral bone leading to symptoms of pain, stiffness and dysfunction. Physiotherapy interventions not only reduce the symptoms but also slows down the disease progression. Neuromuscular Exercise is typically performed in functional weight bearing position and emphasizes the quality of movement and physical function. The aim was to find out the Effect of Neuromuscular Exercises on Pain, Quadriceps strength and Physical function among patients with Osteoarthritis. Methods: 27 patients with OA were selected and underwent Neuromuscular Exercise along with Conventional Quadriceps strengthening exercises, primary outcomes of Quadriceps strength was measured using Handheld dynamometer and Physical function was measured using WOMAC Scale. Results: The statistical analysis was made using ANOVA method, the patients who received Neuromuscular Exercises showed decrease in pain, improvement in Quadriceps strength and Physical Function. The Data analysis was done using ANOVA, and SPSS software v 22.0. The Statistical Analysis showed a significant improvement in Pain after the Neuromuscular Exercises. Pain and Physical function (WOMAC: p&lt;0.05; p = 0.01) and Quadriceps strength (Dynamometer: p&lt;0.05; p = 0.03). Conclusion: The study concluded that Neuromuscular exercises along with conventional therapy was effective in reducing Pain and improving Quadriceps strength and Physical function among patients with Knee Osteoarthritis.

Respiratory and peripheral muscle strength influence recovery of exercise capacity after severe exacerbation of COPD? An observational prospective cohort study

BackgroundPatients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) have decreased exercise tolerance, which may persist for months. In this context, little is known about the associations between muscle strength and recovery of exercise capacity. ObjectiveTo assess whether respiratory and peripheral muscle strength influence recovery of exercise capacity in patients hospitalized due to AECOPD. MethodsTwenty-seven AECOPD patients (aged 69 ± 7 years, 56% male) were included. The following assessments were performed within 24 to 72 h of hospital admission: (i) respiratory muscle strength, measured by maximal inspiratory and expiratory pressures (MIP and MEP); (ii) peripheral muscle strength, assessed by handgrip and quadriceps muscle strength; and (iii) exercise capacity, measured by 6-min walking distance (6MWD). The 6MWD was reassessed 30 days later to determine the recovery of exercise capacity. ResultsAfter 30 days, while 63% of the patients showed clinically important improvement in the 6MWD (recovery ≥ 30 m), 37% showed no change (recovery < 30 m). During hospital stay, the non-recovered group had lower quadriceps muscle strength compared to the recovered group (15 ± 5 vs. 22 ± 6 kgf; P = 0.006), with no significant difference for MIP, MEP and handgrip strength. Only quadriceps muscle strength was associated with recovery of exercise capacity (r = 0.56; P = 0.003). ConclusionAECOPD patients with quadriceps muscle weakness during hospitalization have poor recovery of exercise capacity after 30 days. This finding suggests the importance of early rehabilitation to improve quadriceps strength and accelerate functional recovery after AECOPD.

Psychological readiness at 9 months after anterior cruciate ligament reconstruction –which factors affect?

ObjectiveTo investigate the association of psychological readiness at 9 months after anterior cruciate ligament reconstruction (ACLR) with knee strength and range-of-motion (ROM) at 3 and 9 months postoperatively. DesignRetrospective cohort study. SettingPrivate orthopedic hospital. ParticipantsSeventy-eight patients after ACLR. Main outcomes measuresThe participants completed the anterior cruciate ligament-return to sport after injury (ACL-RSI) scale as an assessment of psychological readiness at 9 months after ACLR. Isometric and isokinetic quadriceps and hamstring strength were measured by a dynamometer at 3 and 9 months postoperatively. Knee extension and flexion ROM were measured in 5° increments with a standard goniometer at 3 and 9 months postoperatively. ResultsUnivariate regression analysis showed that age, limb symmetry index (LSI) of quadriceps strength at 3 and 9 months, and knee extension ROM deficit (>5°) at 3 and 9 months were associated with ACL-RSI scores at 9 months (P < 0.05). Age and LSI of quadriceps strength at 3 months remained significant predictors of ACL-RSI scores at 9 months in multiple regression analysis (R2 = 0.20, P < 0.001). ConclusionsEarly improvements in quadriceps strength after ACLR may have a positive impact on psychological readiness at 9 months postoperatively.