Effects of focal vibration on changes in sports performance in amateur athletes: A randomized clinical trial.

The aim of this study was to evaluate the effectiveness of a focal vibration protocol added to an activation protocol with active muscle contractions and to see what repercussions it has on sprint, countermovement jump (CMJ), and lower limb isometric strength. A double-blind randomized clinical trial was conducted in the Functional Anatomy Laboratory and the sample consisted of 70 athletes. The main outcome measures were knee extension force, CMJ, sprint, and surface electromyography. Repeated-measures analysis of variance revealed significant improvements. They were found in the within-group analysis for the Experimental Group in the isometric extension force (p < 0.001; η2 = 0.368), CMJ (p < 0.001; η2 = 0.301) and 30 m sprint (p < 0.001; η2 = 0.376). In the electromyography, there are changes in the Sham Group in all muscles, in CMJ and Sprint tests, and no differences in the Experimental Group, except for the RF muscle. In the between-group analysis, statistically significant differences were found only in favor of the Experimental Group in CMJ (p = 0.017; η2 = 0.81) and 30 m sprint (p < 0.001; η2 = 0.152). These results confirm a significant improvement in the sprint, CMJ performance, and quadriceps strength, after a focal vibration protocol, added to a muscle active contraction, compared to a focal vibration sham protocol. Therefore, our results suggest that the focal vibration can be a very useful tool in sports involving high-powered actions.

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: To evaluate the effect of minimally invasive ultrasound-guided fascial release and a foot orthoses with first metatarsal head cut-out 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 vs 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 comparation 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). CONCLUSION: The results indicate that the presence of foot orthoses leads to a significant increase in arch height compared to other conditions. Furthermore, when plantar fascia release is performed, the arch does not exhibit any signs of collapse.

Changes in the Sprint, Vertical Jump and Quadriceps Strength after a Capacitive Resistive Electric Transfer Therapy Intervention-A Randomized Clinical Trial.

Generating large mechanical power during actions such as sprinting or jumping is a crucial factor in many sports. These types of actions require a good warm-up activation. Capacitive-Resistive Electric Transfer (CRET) is a non-invasive therapy based on the application of radio frequency electric currents within the range of 300 kHz-1.2 MHz to accelerate tissue metabolic activity. This study aimed to evaluate the effectiveness of adding CRET to an active warm-up protocol in young adult athletes. For the double-blind randomized clinical trial, 60 healthy athletes were recruited and divided into an Experimental group (EG) and a Sham group (SG). EG received a CRET protocol in addition to an active warm-up. SG carried out the same warm-up but with a placebo CRET. The main outcome measures were isometric extension force, countermovement-jump (CMJ), 30 m-sprint test, and surface electromyography (sEMG). There is no statistically significant interaction (group-time) for any of the variables studied. Significant main effects for time were found in isometric extension force (p = 0.008); 30 m sprint (p = 0.017); rectus femoris sEMG during CMJ (p = 0.002); vastus lateralis sEMG during CMJ (p = 0.012); vastus medialis during CMJ (p = 0.010) and rectus femoris sEMG during the 30 m sprint test (p = 0.012). Non-significant differences between means are observed in the isometric extension force (48.91 EG; 10.87 SG) and 30 m sprint (-0.13 EG; -0.04 SG) variables. To conclude, a non-significant tendency was observed in sprint and quadriceps strength following CRET therapy, compared to the individuals' pre-treatment state. Future research should use more treatment sessions to observe this tendency.

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.

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.

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.

Foam Rolling vs. Proprioceptive Neuromuscular Facilitation Stretching in the Hamstring Flexibility of Amateur Athletes: Control Trials.

BACKGROUND: the use of stretching techniques in the sports world is frequent and common thanks to their many effects. One of the main benefits of stretching is an increased range of motion (ROM). Recently, the use of a foam roller has spread in sports practice due to benefits that are similar to those of shoes observed in stretching. The objective of the following study was to compare the results of proprioceptive neuromuscular facilitation stretching (PNF) with foam rolling (FR). METHODS: The design of the study was a single-blind, randomized controlled trial (clinicaltrial.gov NCT05134883), and the participants were 80 healthy young athletes. The range of motion was evaluated with a modified sit-and-reach test before, during (at 30 s), and at the end of the intervention (at 2 min). The subject's discomfort sensation was measured using the Borg scale. Effect sizes were calculated using Cohen's d coefficient. Volunteers were randomized into the PNF group or FR group. RESULTS: the differences were statistically significant (p < 0.001) during the intervention in favor of PNF group. The differences at the end of intervention showed that the PNF group had a greater increase in flexibility, with this difference being statically significant (p < 0.001). The sensation of perceived exertion with PNF at the end of the intervention was similarly classified as moderate for both groups. CONCLUSION: Despite the fact that the use of FR is spreading in the field of sports and rehabilitation, the results of the present study suggest that the gain in flexibility in the hamstrings is greater if PNF-type stretches are used instead of FR.

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.

Study on Balance and Postural Control According to the Stabilometry in Indoor Skydivers: A Cross-Sectional Study.

BACKGROUND: The wind tunnel is a compression cabin through which a stream of air rises homogeneously, generated by fans. To perform different acrobatics, indoor skydivers have to change their body position by turning their body and orientation in reference to the space. Thus, the vestibular, visual and somatosensory systems are subjected to multiple disturbances. Postural control could be affected by altering the visual, vestibular and somatosensory systems during indoor skydiving in the wind tunnel. The aim of this study is to describe the influence of a standard wind tunnel training session on postural control in a normal gravitational situation in indoor skydiving. METHODS: Ten indoor skydivers registered with the Royal Spanish Aeronautical Federation, who had participated in national or international competitions one year ago, were recruited. A single 30 min training session was performed. Postural control was assessed through posturographic analysis using a stabilometric platform immediately before and after the training session. The variables studied were related to the relative position and length of the centre of pressure. RESULTS: No statistically significant changes were found between the initial and final assessment for the posturographic variables studied. CONCLUSIONS: No differences in postural control were found after a standard wind tunnel training session in indoor competition skydivers.

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.

Accuracy and safety of dry needling placement in the popliteus muscle: A cadaveric study.

BACKGROUND: The popliteus muscle attaches posteriorly to the joint capsule of the knee. Although it is an important rotational stabiliser and has been implicated in various knee pathologies, research on its treatment with dry needling is scarce. OBJECTIVE: To determine if a needle accurately and safely penetrates the popliteus muscle during the clinical application of dry needling. METHODS: A cadaveric descriptive study was conducted. Needling insertion of the popliteus muscle was conducted in 11 cryopreserved cadavers with a 50-mm needle. The needle was inserted at upper third of the posterior part of the tibia closest to the knee towards the popliteus. The needle was advanced into the muscle based upon clinician judgement. Cross-sectional anatomical dissections were photographed and analysed by photometry. Safety of the intervention was assessed by calculating the distance from the tip of the needle to the proximate neurovascular structures. RESULTS: Accurate needle penetration of the popliteus muscle was observed in 10 out of 11 (91%) of the cadavers (mean needle penetration: 25.7 ± 6.7mm, 95% CI 21.3-30.3 mm). The distances from the tip of the needle were 17±6mm (95% CI 13-21 mm) to the tibial nerve and 15 ± 0.7mm (95% CI 10-20 mm) to the popliteus vascular bundle. CONCLUSION: The results from this cadaveric study support the notion that needling of the popliteus can be accurately and safely conducted by an experienced clinician. Future studies investigating the clinical effectiveness of these interventions are needed.

Temperature and current flow effects of different electrode placement in shoulder capacitive-resistive electric transfer applications: a cadaveric study.

BACKGROUND: Impingement syndrome is currently estimated to represent 60% of all shoulder pain disorders. Capacitive-Resistive electric transfer therapy is aimed to provoke temperature and current flow changes in superficial and deep tissues. This in vitro study has evaluated the variation of temperature and current flow in the shoulder tissues during two different areas of application of the movable capacitive-resistive electric transfer electrode. METHODS: A cross-sectional study designed, five fresh cryopreserved cadavers (10 shoulders) were included in this study. Four interventions (capacitive and resistive modes; low- and high-power) were performed for 5 min each by a diathermy "T-Plus" device in two shoulder regions: postero-superior and antero-lateral. Supraspinatus tendon, glenohumeral capsule and superficial temperatures were recorded at 1-min intervals and 5 min after treatment. RESULTS: A statistically significant difference was found only for the superficial area and time interaction, with high power-resistive application at the postero-superior shoulder area (P< 0.035). All the applications showed a 5 min after treatment temperature increase compared with the basal data, in all the application points. Superficial temperature in the high power-resistive application showed the greatest percent increase (42.93% ± 22.58), followed by the temperature in the tendon area with the same high power-resistive application (22.97% ± 14.70). The high power-resistive application showed the greatest percent of temperature increase in the applications, reaching 65.9% ± 22.96 at 5-min at the superficial level, and 32% ± 24.25 at 4-min at the level of the supraspinatus tendon. At the capsule level, high power-resistive was also the application that showed the greatest percent of increase, with 21.52% ± 16.16. The application with the lowest percent of temperature increase was the low power-capacitive, with a mean value of 4.86% at supraspinatus tendon level and 7.47% at capsular level. CONCLUSION: The shoulder postero-superior or antero-lateral areas of application of capacitive-resistive electric transfer did not cause statistically significant differences in the temperature changes in either supraspinatus tendon or glenohumeral capsule tissues in cadaveric samples. The high power-resistive application in the postero-superior area significantly increased superficial temperature compared with the same application in the antero-lateral position area.