Cognitive Enhancement Strategies for Older Adults: An Evaluation of Different Training Modalities to Improve Executive Function-A Systematic Review and Meta-Analysis.

(1) Background: The aging population is expected to triple by 2050. Executive functions decline with age, impacting daily tasks, and this is associated with neurodegenerative diseases. Aerobic and resistance exercises positively affect cognitive function in older adults by influencing growth markers. However, the modalities of exercise and the optimal parameters for maximum cognitive benefits remain unclear. (2) Methods: A meta-analysis of randomized clinical trials (RCTs) was conducted. The systematic search was on slowing cognitive decline and performed in the PubMed/MEDLINE and Cochrane Library databases. Articles were included if participants were ≥65 years, healthy, and performing resistance or aerobic exercise, and they were excluded if there was a combination of training and if they have neurological disease or cognitive impairment. (3) Results: The search strategy found a total of 1635 studies. After removing duplicates and assessing the inclusion and exclusion criteria, eight articles were included in the meta-analysis, with a total of 463 healthy older adults analyzed. No significant differences between the intervention groups and the control groups after the aerobic or resistance programs were found. (4) Conclusions: Aerobic exercise interventions improved executive function more than resistance training in older adults, but without statistically significant differences. This can serve as a guide to see, with caution, whether we need a multidisciplinary approach to be more effective in improving the cortical health of older adults.

Relationship Between Knee Frontal Plane Projection Angle and Lower Limb Muscle Activity in Female Athletes.

CONTEXT: Anterior cruciate ligament injuries are directly related to the control of dynamic knee valgus in the landing of a jump, and this is mainly due to the correct activation and neuromuscular function of the lower-extremity muscles. The aim of the study is to assess the relationship between lower limb muscle activity during a single-legged drop jump and knee frontal plane projection angle (FPPA). DESIGN: A correlation study. METHODS: Thirty healthy collegiate female athletes were included in the study. Main outcomes measures were peak knee FPPA and muscle activity (% of maximal voluntary isometric contraction). Peak knee FPPA during a single-legged drop jump test was identified using a 2-dimensional motion analysis system. Muscle activity was assessed using a surface electromyograph for gluteus maximus, gluteus medius, biceps femoris, semitendinosus, vastus medialis quadriceps, vastus lateralis quadriceps, medial gastrocnemius, and lateral gastrocnemius. All variables were assessed for both dominant and nondominant limbs. A correlation analysis between peak knee FPPA and muscle activity was performed. Statistical significance was set at P <.05. RESULTS: A mean peak knee FPPA of 14.52° and 13.38° was identified for dominant and nondominant limb single-legged drop jump test, respectively. Muscle activity (% of maximal voluntary isometric contraction) for muscles assessed ranged from 43.97% to 195.71% during the single-legged drop jump test. The correlation analysis found no significant correlation between any of the muscles assessed and peak knee FPPA during the single-legged drop jump test (Pearson coefficient between -.3 and .1). CONCLUSIONS: There is no association between muscle activity from the lower limb muscles and the knee FPPA during a single-legged drop jump in female athletes. Thus, different muscle properties should be assessed in order to understand such an important movement as the knee FPPA during a jump.

Effects of Plantar Fascia Release and the Use of Foot Orthoses Affect Biomechanics of the Medial Longitudinal Arch of the Foot: A Cadaveric Study.

OBJECTIVE: The aim of the study is to evaluate the effect of minimally invasive ultrasound-guided fascial release and a foot orthoses with first metatarsal head cutout on the biomechanics of the medial longitudinal arch of the foot in cadaveric specimens. DESIGN: A cross-sectional study was designed (20 body donors). Anthropometric measurements of the foot, foot posture index, and the windlass test and force were measured in different conditions: unloaded, loaded position, with foot orthoses, after a 25% plantar fascia release and after a 50% release. RESULTS: For the anthropometric measurements of the foot, differences were found in foot length ( P = 0.009), arch height ( P < 0.001), and midfoot width ( P = 0.019) when comparing the unloaded versus foot orthoses condition. When foot orthoses were compared with 25% plantar fascial release, differences were found in foot length ( P = 0.014) and arch height ( P < 0.001). In the comparison with 50% plantar fascial release, differences were found in the arch height ( P < 0.001). A significant interaction between foot orthoses condition and grades was found in the arch height during the windlass test ( P = 0.021). CONCLUSIONS: The results indicate that the presence of foot orthoses leads to a significant increase in arch height compared with other conditions. Furthermore, when plantar fascia release is performed, the arch does not exhibit any signs of collapse.

Quadriceps and gluteus medius activity during stable and unstable loading exercises in athletes. A cross-sectional study.

The aim of this study was to evaluate the muscle activation of the vastus medialis, vastus lateralis, and gluteus medius during different strength and stability exercises with a water tank compared with a sandbag. A cross-sectional study was conducted in the Functional Anatomy Laboratory, and the sample consisted of 28 athletes. The main outcome measures were surface electromyography (dependent variable), water tank and sandbag, and exercise type (independent variables): Isometric Single Leg Stance (ISLS), One Leg Deadlift (OLDL), Front Rack Forward Lunge (FRFL), and Lateral Lunge (LL). Repeated measures analysis of variance (ANOVA) revealed a significant Group × Time interaction in gluteus medius root mean square (RMS) (F = 14.198, p < 0.001, ŋ2 = 0.35), vastus lateralis RMS (F = 24.374, p < 0.001, ŋ2 = 0.47), and vastus medialis RMS (F = 27.261, p < 0.001, ŋ2 = 0.50). In the between-group analysis, statistically significant differences were observed in gluteus medius RMS in the ISLS: 28.5 ± 15.8 water tank and 20.8 ± 12.6 sandbag (p < 0.001, ŋ2 = 0.08) and OLDL: 29.7 ± 13.3 water tank and 26.5 ± 13.1 sandbag (p < 0.001, ŋ2 = 0.01). In vastus lateralis in ISLS: 30.4 ± 37.6 water tank and 19.0 ± 26.7 sandbag (p < 0.001, ŋ2 = 0.03). In vastus medialis in ISLS: 14.2 ± 13.0 water tank and 7.0 ± 5.6 sandbag (p < 0.001, ŋ2 = 0.12), OLDL: 21.5 ± 16.9 water tank and 15.5 ± 10.7 sandbag (p = 0.002, ŋ2 = 0.04), and LL: 51.8 ± 29.6 water tank and 54.3 ± 29.3 sandbag (p = 0.017, ŋ2 = 0.00). These results confirm significantly greater activation of the gluteus medius and vastus medialis in the ISLS and OLDL exercises, and of the vastus lateralis in the water tank ISLS exercise. However, the vastus medialis shows greater activation in the LL exercise.

Correlation between Power Elbow Flexion and Physical Performance Test: A Potential Predictor for Assessing Physical Performance in Older Adults.

BACKGROUND: With the increasing number of older adults and their declining motor and cognitive function, it is crucial to find alternative methods for assessing physical functionality. The Short Physical Performance Battery (SPPB), the Time Up and Go (TUG) test, the 4 Meter Walk Test and the Barthel Index (BI) have been used to evaluate mobility and fragility and predict falls. But some of these functional test tasks could be difficult to perform for frail older adults or bedridden patients that cannot ambulate. This study aimed to evaluate the relationship between these functional tests and the power elbow flexion (PEF test). MATERIAL AND METHODS: A correlation study was designed with 41 older adults over 65 years of age. The upper limb muscle power was measured using a linear encoder (VITRUBE VBT) with the flexion of the elbow. RESULTS: Strong correlations were found between the PEF test and the 4mWT (rho = 0.715, p = 0.001) and TUG (rho= -0.768, p = 0.001), indicating that the greater the upper limb muscle power is, the greater physical performance will be. Moderate correlations were also found between the PEF and Barthel Index (rho = 0.495, p = 0.001) and SPPB (rho = 0.650, p < 0.001). CONCLUSIONS: There is a strong correlation between PEF and the functional tests, proving that older adults that have greater upper limb muscle power have better physical performance. Upper limb muscle power and PEF could be an interesting tool for the assessment of physical performance in bedridden older adults.

Correlation between Physical Performance and Tensiomyographic and Myotonometric Parameters in Older Adults.

BACKGROUND: To examine the correlation between physical performance and muscle strength and the variables obtained from tensiomyography and myotonometry. METHODS: Fifty-two older adults able to complete functional tests participated in this observational study. Variables of maximal radial muscle displacement (Dm) and contraction time (Tc) (using tensiomyography) and muscle stiffness (using myotonometry) of the rectus femoris and vastus lateralis muscles were assessed. Physical performance (Short Physical Performance Battery, Timed Up and Go, Five Times Sit to Stand, and walking speed), isometric knee extension strength, and grip strength were assessed. A correlation analysis was performed between all the variables. RESULTS: A significant correlation between the Short Physical Performance Battery and the rectus femoris (rho = 0.491) and vastus lateralis Dm (rho = 0.329) was found. Significant correlations between the Five Times Sit to Stand Test and the Dm values of the rectus femoris (rho = -0.340) and Dm (rho = -0.304), and stiffness (rho = -0.345) in the vastus lateralis, were also found. No significant correlations were found between tensiomyography and myotonometry, the Timed Up and Go, and walking speed, nor between tensiomyography and myotonometry and grip strength or isometric knee extension strength. CONCLUSIONS: Functional tests should be prioritized in the assessment of older adults, but further research into muscle quality using technology is advisable.

Effectiveness of Different Training Modalities on Static Balance in Older Adults: A Systematic Review and Meta-Analysis.

(1) Background: aging is associated with functional changes such as balance, which plays a critical role in older adults. Physical exercise has been established as a factor capable of modulating these age-related alterations. (2) Methods: a meta-analysis of randomized clinical trials (RCTs) was conducted. The systematic search was performed in the PubMed/MEDLINE, Web of Science, the SPORTDiscus and Cochrane Library databases. Articles were included if participants were 65 years or older, healthy and performing resistance training, aerobic training, balance training or multicomponent training. Studies were excluded if there was a combination of training with other types of intervention. The protocol of this systematic review was published in the International Prospective Register of Systematic Reviews (PROSPERO) with the code CRD42021233252 (3) Results: the search strategy found a total of 1103 studies. After removing duplicates and the inclusion and exclusion criteria, eight articles were included in the meta-analysis, with a total of 335 healthy older adults analyzed. The results showed no significant differences between the intervention groups and the control groups after the exercise programs. (4) Conclusions: interventions based on different types of exercise improved static balance in elderly population, but without statistically significant difference in comparison with the control groups.

Effect of Load Distribution on Trunk Muscle Activity with Lunge Exercises in Amateur Athletes: Cross-Sectional Study.

BACKGROUND: The effect of load distribution applied to the trunk musculature with lunge exercises has yet to be determined. The aim of this study was to evaluate the effect of load placement using dumbbells on the activation of the latissimus dorsi, erector spinae, external oblique, and rectus abdominis muscles during the lunge. METHODS: Forty-two amateur athletes (21 men and 21 women) were recruited. Three lunge exercises were performed with different loading arrangements (ipsilateral, contralateral, and bilateral). The principal variable recorded for muscle activity was mean "root mean square" expressed as the percentage of the maximal voluntary isometric contraction. RESULTS: There are statistically significant differences in the erector spinae (p < 0.001; p < 0.003) and external oblique muscles (p < 0.009; p < 0.001) compared with the contralateral side. The muscle on the opposite side of the load achieved higher activation for these muscles. The erector spinae and latissimus dorsi muscle did not reach a statistically significant difference with the contralateral side in any exercise (p > 0.05). The higher activation of the latissimus dorsi occurred on the same side on which the load was placed. CONCLUSIONS: There was higher activation of the erector spinae, external oblique, and rectus abdominis muscles contralateral to the side of load placement during lunge exercise by amateur athletes.

Peroneal muscle activity during stable and unstable load exercises. A cross-sectional study.

OBJECTIVE: To evaluate the muscle activity of the peroneus longus during the execution of different unstable load exercises compared to stable load exercises. DESIGN: Cross-sectional study. SETTING: Functional Anatomy Laboratory. PARTICIPANTS: 28 healthy athletes. MAIN OUTCOME MEASURES: Surface electromyography (sEMG), unstable load (water tank), Stable Load (Sandbag), type of exercise (Isometric single leg stance, single-leg Romanian deadlift, front rack forward lunge and lateral lunge). RESULTS: The repeated measures ANOVA revealed significant Group ∗ Time interaction in Root Mean Square (RMS) (F = 51.307, P < 0.001, ŋ2 = 0.70). In the between-group analysis there were statistically significant differences in RMS isometric single leg stance in favor to unstable load (P < 0.001, ŋ2 = 0.07). In the within-group analysis of RMS statistically significant differences were found in the stable load group between isometric single leg stance and single-leg Romanian deadlift (P < 0.001, ŋ2 = 0.05). CONCLUSIONS: Single leg stance exercise with unstable load showed higher peroneus muscle activity than stable load. However, no peroneus muscle activity differences were found between unstable and stable loads for single-leg Romanian deadlift, frontal rack forward lunge and lateral lunge. Single-leg Romanian deadlift with stable load showed higher peroneus muscle activity than isometric single leg stance with stable load.

Effect of respiratory muscle training in asthma: A systematic review and meta-analysis.

BACKGROUND: The last systematic review about respiratory muscle training (RMT) in people with asthma was published almost 10 years ago. Since then, several works have been published. OBJECTIVE: To review the effect of RMT in people with asthma. METHODS: We conducted a systematic review of research included up to September 2021 in PubMed/MEDLINE, PEDro, Scopus, Web of Science, CINAHL, LILACS, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov. We included randomized controlled trials and quasi-experimental studies assessing the effect of RMT on respiratory muscle function, rescue medication, asthma-related symptoms, lung function, exercise capacity, healthcare use, health-related quality of life (HRQoL) and adverse effects in people with asthma. Risk of bias and methodological quality were assessed with the Cochrane Risk of Bias assessment tool and the PEDro scale. Meta-analysis was performed whenever possible; otherwise a qualitative approach was followed. RESULTS: Eleven studies (270 participants) were included, 10 with only adults and were included in the meta-analysis. Inspiratory muscle training (IMT) had beneficial effects on maximal inspiratory pressure (PImax: mean difference [MD] 21.95 cmH2O [95% confidence interval [CI] 15.05; 28.85]), with no changes in maximal expiratory pressure (MD 14.97 cmH2O [95%CI -5.65; 35.59]), lung function (forced expiratory volume in 1 sec: MD 0.06 [95%CI -0.14; 0.26] L; force vital capacity: MD 0.39 [95%CI -0.24; 1.02] L) and exercise capacity (standard mean difference [SMD] 1.73 [95%CI -0.61; 4.08]). Subgroup analysis revealed that IMT load >50% PImax and duration >6 weeks were beneficial for exercise capacity. The qualitative analysis suggested that IMT may have benefits on respiratory muscle endurance, rescue medication and exertional dyspnoea, with no adverse effects. CONCLUSIONS: This systematic review and meta-analysis showed a significant increase in PImax after IMT in adults with asthma and reinforced the relevance of the dose-response principle of training. More evidence is needed to clarify the effect of IMT in respiratory muscle endurance, rescue medication, exercise capacity, healthcare use and HRQoL. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42020221939; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=221939.

Effectiveness of multicomponent training on physical performance in older adults: A systematic review and meta-analysis.

Multicomponent training (MCT) is characterized by the combination of at least 3 types of training. The purpose of this meta-analysis was to assess the effectiveness of MCT programs for improving physical performance in healthy older adults. A systematic review and meta-analysis of randomized control trials (RCTs) was conducted. The systematic search was performed in the Web of Sciences, PubMed (MEDLINE), and Cochrane Library databases. Articles were included if participants were healthy and 65 years or older, and the control group did not perform any type of training. Studies were excluded if the interventions lasted less than 8 weeks. PEDro scale and Risk of Bias tool (RoB) were used in order to assess the quality of the articles. The search strategy found a total of 388 studies. After inclusion and exclusion criteria, 19 studies were included for the qualitative analysis. Finally, 13 articles were included in the meta-analysis, with a total of 808 healthy older adults analyzed. The main results of the meta-analysis showed that MCT improves physical performance significantly more than no training (SMD: 0.78; 95% CI: 0.55, 1.00; Z = 6.84, p < 0.01; I2 = 54%). In addition, the MCT also seems to significantly increase in upper and lower limb strength, walking speed and aerobic capacity. MCT improves general functionality, strength in upper and lower extremities, walking speed and aerobic capacity. Implementation of MCT programs should be encouraged as an effective strategy in the prevention of adverse conditions in the older adult.

Effects of Adding an Online Exercise Program on Physical Function in Individuals Hospitalized by COVID-19: A Randomized Controlled Trial.

The worldwide pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has impacted all healthcare systems. One potential sequela experienced by hospitalized coronavirus disease 2019 (COVID-19) survivors includes muscle weakness with a reduction in strength and, consequently, a possible increase in frailty. The aim of this clinical trial was to evaluate the efficacy of adding an online therapeutic exercise program for 8 weeks to the medical prescriptions on functional variables in patients hospitalized due to COVID-19. A randomized controlled trial including 70 previously hospitalized COVID-19 survivors was conducted. Patients were randomly allocated to an experimental (n = 35) or control (n = 35) group. Both groups received regular prescriptions provided by their medical doctors. The experimental group also received a live online therapeutic exercise program for 8 weeks (3 sessions/week). Handgrip strength, gait speed, lower-extremity strength, balance, and frailty were assessed at baseline, at the end of the program, and one month after the end of the intervention. The repeated measures analysis of variance revealed significant Group*Time interactions for all the outcomes: (handgrip dominant: F = 17.395, p < 0.001, η2 = 0.24; handgrip non-dominant: F = 33.197, p < 0.001, η2 = 0.33; 4 m walk test (4WT): F = 13.039, p = 0.001, η2 = 0.16; short physical performance battery (SPPB): F = 26.421, p < 0.001, η2 = 0.28; the five chair-raise test (5CRT): F = 5.628, p = 0.004, η2 = 0.08; FRAIL scale: F = 11.249, p = 0.001, η2 = 0.14): patients in the experimental group experienced greater improvements in all outcomes than those assigned to the control group. This study revealed that the addition of an online exercise program for 8 weeks obtained greater improvements in handgrip strength, gait speed, lower-extremity strength, balance, and frailty in a sample of previously hospitalized COVID-19 survivors than application of just usual medical prescription.

Correlation between Physical Performance and Stabilometric Parameters in Older Adults.

Background and Objectives: Falls are a common and serious threat to the health and independence of older adults. The decrease in functional capacity during aging means an increased risk of falls. To date, it is not known whether there is a relationship between balance and functional tests. The aim of the study was to evaluate the correlation between eyes-open and eyes-closed static balance with different functional tests. Materials and Methods: A correlation study was designed with 52 healthy subjects over 65 years of age. Results: Regarding the open eyes stabilometric parameters, significant correlations observed between the surface and the functional tests were weak in all cases. The correlations observed between length and the functional tests performed were moderate, except for that of the Timed Up and Go test (TUG) which was weak. No significant correlation between TUG and surface was found. Regarding the closed eyes stabilometric parameters, statistically significant moderate correlations were found between the surface and the Short Physical Performance Battery (SPPB) and the Five Times Sit to Stand test (5XSST). In the case of the length with eyes closed, a statistically significant moderate correlation (rho = 0.40-0.69) was found with the SPPB and 5XSST variables, and weak correlations with the 4 m Walk Speed test (4WS) and TUG variables. Conclusions: There is a mild to moderate correlation between some functional tests and stabilometric parameters in adults over 65 years old.

Immediate effects of diacutaneous fibrolysis in athletes with hamstring shortening. A randomized within-participant clinical trial.

BACKGROUND: Diacutaneous fibrolysis is a non-invasive instrumental physiotherapeutic technique, used to treat mechanical or inflammatory pain and normalize function in the musculoskeletal system. Different studies have reported positive effects on range of motion, strength or function in musculoskeletal disorders, mainly in the upper extremity. The incidence and recurrence rates of hamstring injuries are high in many sports. However, there are no studies assessing these parameters in the hamstring and gluteus maximus in athletes. Objective. To evaluate the immediate and 30 minutes post-treatment effects of a single diacutaneous fibrolysis session on hamstring length, flexibility, muscle strength, myoelectrical activity and lower limb performance in athletes with hamstring shortening. METHODS: A randomized within-participant clinical trial. Sixty-six athletes with hamstring shortening were recruited. A single session of diacutaneous fibrolysis was applied following the cetripetal protocol to the gluteus maximus, biceps femoris and semitendinosus of for the experimental lower limb, whereas the control limb was not treated. Hamstring length (Passive knee extension test), hamstring and low back flexibility (Modified back saver sit and reach test), hamstring and gluteus maximus strength and electrical activity (dynamometry and surface electromyography, respectively) and lower limb performance (Countermovement Jump) were tested before treatment (T0), after treatment (T1), and 30 minutes post-treatment (T2). RESULTS: We only found a statistically significant difference between T0-T2 for the hamstring length favouring the experimental limbs (p<0.001). There were no statistically significant changes for hamstring and lower back flexibility, strength and electrical activity outcomes between groups. In the countermovement jump, we found a decrease of 0.58 cm in the high jump and a decrease of 9.19 N in the power jump at T1. These values recovered and improved at T2. However, these changes were not statistically significant (p>0.05). CONCLUSIONS: A single session of diacutaneous fibrolysis in athletes with hamstring shortening, following the centripetal protocol for the posterior part of the thigh, produces improvements in hamstring length 30 minutes after, and in gluteus maximus strength immediately and 30 minutes after the treatment. It seems to have no effects on the overall hamstring and lower back flexibility or myoelectric activity. Importantly, the lower limb performance was not impaired after the treatment.

Sex Differences in Pre-Season Anthropometric, Balance and Range-of-Motion Characteristics in Elite Youth Soccer Players.

In soccer, injury epidemiology differs between males and females. It is clinically useful to know whether there are between-sex differences in selected characteristics relevant to primary injury risk and injury prevention practices. The purpose of this study was to explore between-sex differences in anthropometric, balance, and range-of-motion characteristics in Spanish elite male and female youth soccer players. This was a pre-season cross-sectional study. Sixty-nine males (age 16.8 ± 0.9 yr; height 175.9 ± 6.8 cm; mass 67.9 ± 6.3 kg) and thirty-seven females (age 17.2 ± 1.7 yr; height 164.0 ± 6.3 cm; mass 59.0 ± 5.8 kg) participated. Anthropometrics (standing/sitting height, bodymass, right/left leg length) and right/left anterior reach test (ART), hip internal/external active range of motion, active knee extension (AKE), and weightbearing lunge test (WBLT) were measured. Between-sex differences were assessed with Bonferroni-corrected Mann−Whitney U tests and Cliff's delta (d). Between-sex significant differences (p < 0.003, d ≥ 0.50) were observed for anthropometric data and for hip internal rotation. No between-sex significant differences were observed for ART/AKE/WBLT measures. Between-sex significant differences with large effect sizes were identified for anthropometric data and right/left hip internal rotation. The present study adds new data to the literature for young Spanish male and female soccer players. The present findings will help inform clinical reasoning processes and future injury prevention research for elite male and female youth soccer players.

Effectiveness of Blood Flow Restriction Training on Muscle Strength and Physical Performance in Older Adults: A Systematic Review and Meta-analysis.

OBJECTIVE: To analyze the effectiveness of the blood flow restriction training in improving muscle strength and physical performance in older adults. DATA SOURCES: A systematic review and meta-analysis of randomized controlled trials was conducted. The Cochrane Library, PubMed, Web of Sciences, PEDro, Scopus, and ScienceDirect databases were systematically searched. STUDY SELECTION: Articles were included if participants were 60 years or older and were considered healthy. DATA EXTRACTION: The search strategy found a total of 363 studies. Finally, 10 articles were included in the systematic review, with a total of 278 healthy older adults analyzed. DATA SYNTHESIS: The main results of the meta-analysis showed a statistical difference of muscle strength in favor of blood flow restriction training when compared with conventional training and no statistical differences when compared with high-intensity resistance training. Physical performance showed a nonstatistical difference between the blood flow restriction training, conventional training, and no training groups. CONCLUSIONS: Blood flow restriction training is an interesting alternative to high-intensity strength training for improving muscle strength in older individuals who cannot perform high-load exercises.

Effectiveness of a Multicomponent Training Program on Physical Performance and Muscle Quality in Older Adults: A Quasi-Experimental Study.

Aging is associated with a decrease in functional capacity, manifested by a loss of strength, physical performance and muscle quality. Multicomponent training (MCT), characterized by the combination of at least three types of training, could be a good strategy to counteract these changes. To date there are no studies evaluating the effectiveness of MCT in improving both physical performance and muscle quality simultaneously. The aim of this study is to evaluate the changes produced by an MCT program on both physical performance and muscle quality in a population of healthy older adults. Sixteen healthy older adults were recruited to perform a 15-session multicomponent training intervention. Physical performance was assessed by different functional tests, and muscle quality was assessed by tensiomyography and myotonometry. The main results of this study show some improvement in functional tests, but not in muscle quality parameters, except for vastus lateralis stiffness. MCT is able to generate improvements in the physical performance of older adults, but these improvements are not reflected in muscle quality parameters measured by tensiomyography and myotonometry.

Does Self-Myofascial Release Cause a Remote Hamstring Stretching Effect Based on Myofascial Chains? A Randomized Controlled Trial.

BACKGROUND: The hamstring muscles are described as forming part of myofascial chains or meridians, and the superficial back line (SBL) is one such chain. Good hamstring flexibility is fundamental to sporting performance and is associated with prevention of injuries of these muscles. The aim of this study was to measure the effect of self-myofascial release (SMR) on hamstring flexibility and determine which segment of the SBL resulted in the greatest increase in flexibility. METHODS: 94 volunteers were randomly assigned to a control group or to one of the five intervention groups. In the intervention groups, SMR was applied to one of the five segments of the SBL (plantar fascia, posterior part of the sural fascia, posterior part of the crural fascia, lumbar fascia or epicranial aponeurosis) for 10 min. The analyzed variables were hamstring flexibility at 30 s, 2, 5, and 10 min, and dorsiflexion range of motion before and after the intervention. RESULTS: Hamstring flexibility and ankle dorsiflexion improved when SMR was performed on any of the SBL segments. The segments with the greatest effect were the posterior part of the sural fascia when the intervention was brief (30 s to 2 min) or the posterior part of the crural fascia when the intervention was longer (5 or 10 min). In general, 50% of the flexibility gain was obtained during the first 2 min of SMR. CONCLUSIONS: The SBL may be considered a functional structure, and SMR to any of the segments can improve hamstring flexibility and ankle dorsiflexion.

Relationship between lower limb EMG activity and knee frontal plane projection angle during a single-legged drop jump.

OBJECTIVES: To assess a relationship between lower limb muscle activity and the frontal plane knee kinematics during a single-legged drop jump. DESIGN: Correlation study; SETTING: Functional Anatomy Laboratory. PARTICIPANTS: 35 healthy collegiate male athletes. MAIN OUTCOME MEASURES: Muscle activity (%MVIC) of gluteus maximus, gluteus medius, biceps femoris, semitendinosus, vastus medialis quadriceps, vastus lateralis quadriceps, medial gastrocnemius and lateral gastrocnemius; peak knee frontal plane projection angle; and Pearson's correlation coefficients between muscle activity and peak knee frontal plane projection angle. All outcomes were assessed for both dominant and non-dominant limbs. RESULTS: Significant correlations (r = 0.46-0.60, P < 0.05) were found between the muscle activities of the gluteus maximus, gluteus medius, biceps femoris, and semitendinosus, when compared to the knee frontal plane projection angle. CONCLUSION: Gluteal muscles and hamstring muscles are associated with the peak knee frontal plane projection angle during a single-legged drop jump test. Thus, gluteal and hamstring muscle activities should be considered when developing rehabilitation or injury prevention programs.

Biceps Femoris Activation during Hamstring Strength Exercises: A Systematic Review.

BACKGROUND: The aim of the study was to systematically evaluate the biceps femoris long head activation across cross-sectional hamstring strength exercise studies. METHODS: A systematic review design was followed. The search strategy conducted in PubMed, Cochrane Library, and Web of Sciences databases found a total of 3643 studies. Once inclusion and exclusion criteria were applied, 29 studies were finally included in this systematic review. A total of 507 participants and 114 different exercises were analyzed. Exercises were evaluated individually and grouped into several categories: Nordics, isokinetic exercises, lunges, squats, deadlifts, good mornings, hip thrusts, bridges, leg curls, swings, hip and back extensions, and others. RESULTS: Results showed the isokinetic and Nordic exercises as the categories with highest biceps femoris activation (>60% of Maximal Voluntary Isometric Contraction). Nordic hamstring exercise ankle dorsiflexion was the exercise that achieved the highest biceps femoris long head activation (128.1% of its Maximal Voluntary Isometric Contraction). CONCLUSIONS: The results from this systematic review suggest that isokinetic and Nordic exercises seem to be the best option to activate biceps femoris long head. Future studies evaluating the implementation of these exercises in prevention programs are needed.