Neuromuscular Capacity Research Articles

The Validity of the 2-Point Method for Assessing the Force-Velocity Relationship of the Knee Flexors and Knee Extensors: The Relevance of Distant Force-Velocity Testing.

Over the past decade, force-velocity (F-v) profiling has emerged as a promising tool for assessing neuromuscular capacity to design individually tailored interventions in diverse populations. To date, a limited number of studies have addressed the optimization of the linear method for measuring F-v profiles of single-joint isokinetic movements. We aimed to simplify the measurement of knee extension (KE) and knee flexion (KF) isokinetic tasks by evaluating the most appropriate combination of two velocities (i.e., the 2-point method). Twenty-two healthy participants (11 males and 11 females) were included in the study. Isokinetic peak torque was measured at nine angular velocities (30-60-90-120-150-180-210-240-300°/s) and under isometric conditions (at 150° and 120° of KF for KE, and KF, respectively). Maximal theoretical force (F0), maximal theoretical velocity (v0), slope of the relationship (Sfv) and maximal theoretical power (Pmax) were derived from the linear F-v profiles of KE and KF and compared between the 9-point method and all possible combinations (36 in total) of the 2-point methods. The F-v profiles obtained from nine points were linear for KE (R2 = 0.95; 95% CI = 0.94–0.96) and KF (R2 = 0.93; 95% CI = 0.90–0.95), with F0 underestimating isometric force. Further analyses revealed great to excellent validity (range: ICCs = 0.89–0.99; CV = 2.54%–4.34%) and trivial systematic error (range: ES = −0.11–0.24) of the KE 2-point method when force from distant velocities (30°/s, 60°/s or 90°/s combined with 210°/s, 240°/s or 300°/s) was used. Similarly, great to excellent validity and trivial systematic error of the KF 2-point method for F0 and Pmax (range: ICC = 0.90–0.96; CV = 2.94%–6.38%; ES = −0.07–0.14) were observed when using the previously described combinations of velocities. These results suggest that practitioners should consider using more distant velocities when performing simplified isokinetic 2-point single-joint F-v profiling. Furthermore, the F-v profile has the potential to differentiate between the mechanical properties of knee extensors and flexors and could therefore serve as a potential descriptor of performance.

Le syndrome post-réanimation (SPR) et les programmes de réhabilitation post-réanimation

In 2021, the issue of intensive care hospitalization is no longer just survival in the acute phase, but also reducing the post-intensive care consequences. Post-intensive care syndrome (PICS) affects approximately 50–70% of patients upon discharge from intensive care. This entity includes psychological disorders, impaired neuromuscular capacities, cognitive disorders and organ dysfunctions that may persist for months or years impairing the quality of life of the patients and their families. The current COVID-19 crisis has incredibly increased the number of patients who could develop PICS, and support the urgent need for screening these patients, in order to prevent possible sequelae of intensive care. There are different types of “post-intensive care” follow-up, even their interest is debated. However, early detection of PICS is important to address the patients to supportive program of care. The intensive care physicians really need to identify PICS in their patients and coordinate their management distant from the ICU hospitalisation.

Load-Velocity Relationship Variables to Assess the Maximal Neuromuscular Capacities During the Back-Squat Exercise.

The relationship between the external load lifted and movement velocity can be modeled by a simple linear regression, and the variables derived from the load-velocity (L-V) relationship were recently used to estimate the maximal neuromuscular capacities during 2 variants of the back-squat exercise. The L-V relationship variables will be highly reliable and will be highly associated with the traditional tests commonly used to evaluate the maximal force and power. Twenty-four male wrestlers performed 5 testing sessions (a 1-repetition maximum [1RM] session, and 4 experimental sessions [2 with the concentric-only back-squat and 2 with the eccentric-concentric back-squat]). Each experimental session consisted of performing 3 repetitions against 5 loads (45%-55%-65%-75%-85% of the 1RM), followed by single 1RM attempts. Level 3. Individual L-V relationships were modeled from the mean velocity collected under all loading conditions from which the following 3 variables were calculated: load-axis intercept (L0), velocity-axis intercept (v0), and area under the line (Aline = L0·v0/2). The back-squat 1RM strength and the maximum power determined as the apex of the power-velocity relationship (Pmax) were also determined as traditional measures of maximal force and power capacities, respectively. The between-session reliability was high for the Aline (coefficient of variation [CV] range = 2.58%-4.37%; intraclass correlation coefficient [ICC] range = 0.98-0.99) and generally acceptable for L0 and v0 (CV range = 5.08%-9.01%; ICC range = 0.45-0.96). Regarding the concurrent validity, the correlations were very large between L0 and the 1RM strength (rrange = 0.87-0.88) and nearly perfect between Aline and Pmax (r = 0.98-0.99). The load-velocity relationship variables can be obtained with a high reliability (L0, v0, and Aline) and validity (L0 and Aline) during the back-squat exercise. The load-velocity relationship modeling represents a quick and simple procedure to estimate the maximal neuromuscular capacities of lower-body muscles.

Age-related changes in protective arm reaction kinematics, kinetics, and neuromuscular activation during evoked forward falls.

Fall related injuries in older adults are a major healthcare concern. During a fall, the hands and arms play an important role in minimizing trauma from ground impact. Although older adults are able to orient the hands and arms into a protective orientation after falling and prior to ground impact, an inability to avoid increased body impact occurs with age. Previous investigations have generally studied rapid arm movements in the pre-impact phase or absorbing energy in the post-impact phase. There are no known studies that have directly examined both the pre-impact and post-impact phase in sequence in a forward fall. The aim of this study was to identify age-related biomechanical and neuromuscular changes in evoked arm reactions in response to forward falls that may increase fall injury risk. Fourteen younger and 15 older adults participated. Falls were simulated while standing with torso and legs restrained via a moving pendulum system from 4 different initial lean angles. While there was not a significant age-related difference in the amount of energy absorbed post-impact (p=0.68), older adults exhibited an 11% smaller maximum vertical ground reaction force when normalized to body weight (p=0.031), and 8 degrees less elbow extension at impact (p=0.045). A significant interaction between age and initial lean angle (p=0.024), indicated that older adults required 54%, 54%, 41%, and 57% greater elbow angular displacement after impact at the low, medium, medium-high, and high initial lean angles compared to younger adults. These results suggested older adults may be at greater risk of increased body impact due to increased elbow flexion angular displacement after impact when the hands and arms are able to contact the ground first. Both groups exhibited robust modulation to the initial lean angle with no observed age-related differences in the initial onset timing or amplitude of muscle activation levels. There were no significant age-related differences in the EMG timing, amplitude or co-activation of muscle activation preceding impact or following impact indicating comparable neuromotor response patterns between older and younger adults. These results suggest that aging changes in muscular elements may be more implicated in the observed differences than changes in neuromuscular capacity. Future work is needed to test the efficacy of different modalities (e.g. instruction, strength, power, perturbation training, fall landing techniques) aimed at reducing fall injury risk.

Potential Benefits of a Minimal Dose Eccentric Resistance Training Paradigm to Combat Sarcopenia and Age-Related Muscle and Physical Function Deficits in Older Adults.

The ability of older adults to perform activities of daily living is often limited by the ability to generate high mechanical outputs. Therefore, assessing and developing maximal neuromuscular capacity is essential for determining age-related risk for functional decline as well as the effectiveness of therapeutic interventions. Interventions designed to enhance neuromuscular capacities underpinning maximal mechanical outputs could positively impact functional performance in daily life. Unfortunately, < 10% of older adults meet the current resistance training guidelines. It has recently been proposed that a more “minimal dose” RT model may help engage a greater proportion of older adults, so that they may realize the benefits of RT. Eccentric exercise offers some promising qualities for such an approach due to its efficiency in overloading contractions that can induce substantial neuromuscular adaptations. When used in a minimal dose RT paradigm, eccentric-based RT may be a particularly promising approach for older adults that can efficiently improve muscle mass, strength, and functional performance. One approach that may lead to improved neuromuscular function capacities and overall health is through heightened exercise tolerance which would favor greater exercise participation in older adult populations. Therefore, our perspective article will discuss the implications of using a minimal dose, submaximal (i.e., low intensity) multi-joint eccentric resistance training paradigm as a potentially effective, and yet currently underutilized, means to efficiently improve neuromuscular capacities and function for older adults.

Feasibility of the 2-point method to determine the load−velocity relationship variables during the countermovement jump exercise

PurposeThis study aimed to examine the reliability and validity of load−velocity (L–V) relationship variables obtained through the 2-point method using different load combinations and velocity variables. MethodsTwenty men performed 2 identical sessions consisting of 2 countermovement jumps against 4 external loads (20 kg, 40 kg, 60 kg, and 80 kg) and a heavy squat against a load linked to a mean velocity (MV) of 0.55 m/s (load0.55). The L–V relationship variables (load-axis intercept (L0), velocity-axis intercept (v0), and area under the L–V relationship line (Aline)) were obtained using 3 velocity variables (MV, mean propulsive velocity (MPV), and peak velocity) by the multiple-point method including (20–40–60–80–load0.55) and excluding (20–40–60–80) the heavy squat, as well as from their respective 2-point methods (20–load0.55 and 20–80). ResultsThe L–V relationship variables were obtained with an acceptable reliability (coefficient of variation (CV) ≤ 7.30%; intra-class correlation coefficient ≥ 0.63). The reliability of L0 and v0 was comparable for both methods (CVratio (calculated as higher value/lower value): 1.11–1.12), but the multiple-point method provided Aline with a greater reliability (CVratio = 1.26). The use of a heavy squat provided the L–V relationship variables with a comparable or higher reliability than the use of a heavy countermovement jump load (CVratio: 1.06–1.19). The peak velocity provided the load–velocity relationship variables with the greatest reliability (CVratio: 1.15–1.86) followed by the MV (CVratio: 1.07–1.18), and finally the MPV. The 2-point methods only revealed an acceptable validity for the MV and MPV (effect size ≤ 0.19; Pearson's product-moment correlation coefficient ≥ 0.96; Lin's concordance correlation coefficient ≥ 0.94). ConclusionThe 2-point method obtained from a heavy squat load and MV or MPV is a quick, safe, and reliable procedure to evaluate the lower-body maximal neuromuscular capacities through the L–V relationship.

Investigation of Inter-Limb Symmetry in Knee Extensors Using Different Strength Outcome Measures.

Muscle performance between contra-lateral knee extensors is most often assessed using maximal test for isometric/isokinetic torque evaluation. Recently, the rate of force development scaling factor (RFD-SF) has been used to evaluate neuromuscular capacity with a range of submaximal target peak torques, which could highlight other aspects of inter-limb (a)symmetry. The aim of our study was to investigate the differences, associations, and agreement between inter-limb symmetries of knee extensors using maximal torque (Tmax) rate of torque development (RTD), slope of the RFD-SF regression line (k), and theoretical peak of RTD (TPRTD). A total of 236 young, healthy athletes participated in the cross-sectional study. All participants performed unilateral knee extension (maximal voluntary contraction protocol and RFD-SF protocol) with both legs in the isometric knee dynamometer. Inter-limb symmetries were calculated for each outcome measure. Our results showed significant differences between all symmetry values (Tmax (91.7%), RTD (85.2%), k (94.2%), TPRTD (95.9%)). Significant strong correlations were found between symmetry values calculated from k and TPRTD (r = 0.88, p < 0.001), while weak correlation was found between Tmax and RTD (r = 0.17, p < 0.01. Fair agreement regarding leg dominance was found between Tmax and RTD values. Our results suggest that inter-limb (a)symmetries are metric- and task-specific.

Validation of a novel method to assess maximal neuromuscular capacities through the load-velocity relationship

This study was designed to elucidate whether the assessment of the load-velocity relationship during the bench press throw exercise can be used as an indicator of the maximal capacity of upper-body muscles to produce force at low and high velocities as well as doing work at a maximal rate. Twenty-four resistance-trained men (bench press one-repetition maximum [1RM] relative to body mass = 1.14 ± 0.17) performed two incremental loading tests from 14 kg until the 1RM during the bench press throw exercise 7 days apart. Individual load-velocity relationships were modelled from the mean velocity values collected under all loading conditions and three variables were calculated from the individual load-velocity relationships: load-axis intercept (L0), velocity-axis intercept (v0), and area under the line (Aline = L0·v0/2). The bench press 1RM strength, peak velocity achieved against 14 kg (PV14kg), and the maximum power determined as the apex of the power-velocity relationship (Pmax) were also determined as traditional measures of maximal neuromuscular capacities. The three load-velocity relationship variables showed a very high reliability (CV ≤ 2.36%; ICC ≥ 0.86). Regarding the concurrent validity of the load-velocity relationship variables, nearly perfect correlations were observed between L0 and 1RM strength (r = 0.98) and between Aline and Pmax (r = 0.96), while lower correlations were observed between v0 and PV14kg (r = 0.59). These results highlight that the three maximal mechanical capacities of upper-body muscles can be quickly estimated through the assessment of the load-velocity relationship during the bench press throw exercise.

67. The value of overall assessment in adult degenerative scoliosis patients: short- and long-term effect of surgical intervention on static and dynamic balance, gait and pain level

<h3>BACKGROUND CONTEXT</h3> In the diagnosis and treatment of adult spinal deformities, static radiographic measurements in the sagittal and coronal anatomical planes and patient-reported outcome measures (PROMs) serve as the gold standard for assessment of spinal alignment and deformity. However, there is a lack of published literature on their relation to objective functional outcome measures (FOMs) among patients afflicted with adult spinal deformity. Adult spinal deformity (ASD) is due to degeneration, functional decline is partly due to loss of postural stability and neuromuscular capacity and coordination. Objective functional measures (eg, static standing and walking alignment) cover more information than just radiographic alignment in the ASD population. Gait and dynamic balance analysis can reveal functional compensatory alignment changes where static imaging is limited. Previous studies have shown improvement in postoperative gait, approximating non-ASD control cohorts but still symptomatic. Many studies have shown surgical reconstruction in ASD patients has improved patient outcomes, but not overall assessment of objective function along with psychological factors. Therefore, a more comprehensive standard outcome measurement is needed. <h3>PURPOSE</h3> To determine the one-year effects of spinal alignment on function in ASD patients following surgical treatment using radiographic parameters, 3D gait and balance analysis, PROMs, and psychological tests and compared to healthy control. <h3>STUDY DESIGN/SETTING</h3> Nonrandomized, prospective study. <h3>PATIENT SAMPLE</h3> Forty-three symptomatic ASD patients, 24 age-matched control. <h3>OUTCOME MEASURES</h3> Gait spatiotemporal parameters, dynamic balance as measurement by balance effort and Cone of Economy (CoE) dimensions, radiograph alignment measurements, PROMs, and psychological factors. <h3>METHODS</h3> Patients performed dynamic balance and gait evaluations prior to surgery (Pre), 3 months (Post3), and 12 months (Post12) postoperatively. Patients also completed full-length, head-to-toe, micro-dose X-rays along with PROMs, and psychological questionnaires. Balance effort and CoE dimensions were measured by total sway and range of sway, respectively. Repeated measurement analysis of variance (ANOVA) and one-way ANOVA were used to determine differences in radiographic, dynamic balance, gait, and PROMs parameters at Post3 and Post12 and to the match control group. <h3>RESULTS</h3> Significant improvements in radiographic alignment were found in Cobb angle (<0.001), sagittal (<0.009) and coronal (<0.003) vertical axes and pelvic incidence-lumbar lordosis mismatch (<0.001) at Post3 and Post12. There were significant improvements in all PROMs after surgery (VAS mid-back, low back, and leg, ODI and SRS). Surgical intervention resulted in a significant decrease in balance effort (head: p<0.017 and center of mass: p<0.042) and reduced in the CoE dimensions (sagittal: p<0.004; and coronal: p=0.029). Gait was also enhanced after surgery as seen with a faster walking speed (p<0.024) and longer stride length (p<0.024). Psychological factors showed significant improvements in Tampa Scale for Kinesiophobia and Fear Avoidance Belief Questionnaire scores (p<0.050). <h3>CONCLUSIONS</h3> This is the first study to provide insight into a comprehensive global assessment of ASD surgery patients' function which includes complete objective functional and psychological outcomes in addition to standard PROMs and radiographic alignment. Balance effort and CoE limits improved at all time points post-operatively and ultimately matched the controls at 12 months. Similar to the significant improvement in static and dynamic balance in these patient groups, gait parameters also improved Post3 and Post12 to closely resemble the control group and continued to improve over time. Our findings present a more comprehensive set of outcome metrics, which, once combined, provide a more detailed and sensitive assessment of overall treatment outcomes. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

No effect of passive stretching on neuromuscular function and maximum force-generating capacity in the antagonist muscle

PurposeThe present study investigated whether or not passive stretching increases the force-generating capacity of the antagonist muscle, and the possible neuromuscular mechanisms behind.MethodsTo this purpose, the neuromuscular function accompanying the force-generating capacity was assessed in 26 healthy male volunteers after passive stretching and in a control session. Before and after passive intermittent static stretching of the plantar flexors consisting of five sets × 45 s + 15 s-rest, maximum voluntary isometric contraction (MVC) and surface electromyographic root mean square (sEMG RMS) were measured in the tibialis anterior (the antagonist muscle). Additionally, evoked V wave, H-reflex, and M wave were elicited by nerve stimulation at rest and during MVC. Ankle range of motion (ROM) and plantar flexors MVC and EMG RMS were measured to check for the effectiveness of the stretching manoeuvre.ResultsNo change in MVC [p = 0.670; effect size (ES) − 0.03] and sEMG RMS/M wave during MVC (p = 0.231; ES − 0.09) was observed in the antagonist muscle after passive stretching. Similarly, no change in V wave (p = 0.531; ES 0.16), H-reflex at rest and during MVC (p = 0.656 and 0.597; ES 0.11 and 0.23, respectively) and M wave at rest and during MVC (p = 0.355 and 0.554; ES 0.04 and 0.01, respectively) was observed. An increase in ankle ROM (p < 0.001; ES 0.55) and a decrease in plantar flexors MVC (p < 0.001; ES − 1.05) and EMG RMS (p < 0.05; ES − 1.72 to − 0.13 in all muscles) indicated the effectiveness of stretching protocol.ConclusionNo change in the force-generating capacity and neuromuscular function of the antagonist muscle after passive stretching was observed.

Traditional Free-Weight Vs. Variable Resistance Training Applied to Elite Young Soccer Players During a Short Preseason: Effects on Strength, Speed, and Power Performance.

Loturco, I, Pereira, LA, Reis, VP, Zanetti, V, Bishop, C, and Mcguigan, MR. Traditional free-weight vs. variable resistance training applied to elite young soccer players during a short preseason: Effects on strength, speed, and power performance. J Strength Cond Res 36(12): 3432-3439, 2022-Maximizing the neuromuscular capacities of players is a critical challenge during short soccer preseasons. This study compared the effects of 2 strength-power training regimes, on the strength, speed, and power performance of elite young soccer players during a 4-week preseason. Twenty-five under-20 players from the same club were pair matched in 2 training groups as follows: traditional training group (TTG) ( n = 13), athletes performed half-squat (HS) and jump-squat (JS) exercises as traditionally prescribed, and elastic band (EB) group (EBG) ( n = 12), athletes performed HS and JS with EB attached to the barbell. Vertical jump height, 20-m sprint velocity, change of direction (COD) speed, HS and JS power, and 1 repetition maximum (1RM) in the HS were assessed before, after 2-week, and after 4-week of training. A two-way analysis of variance with repeated measures was used to assess the effects of both training protocols over the experimental period. Both strategies were effective for significantly improving HS and JS power (effect sizes [ESs] = 1.00-1.77), HS 1RM (ES = 1.68 and 1.51 for TTG and EBG, respectively), vertical jumping ability (ES = 0.37-0.65), and COD speed (ES = 0.81 and 0.39 for TTG and EBG, respectively), when comparing premeasures and postmeasures. By contrast, both TTG and EBG failed to increase 20-m sprint velocity (ES ranging between -0.54 and 0.23). In conclusion, both training schemes were able to improve the strength and power performance but not the sprint capacity of young soccer players. To accelerate strength gains over very-short time periods (i.e., 2 weeks), variable resistance training may be advantageous. Conversely, to optimize power adaptations in ballistic exercises across a similar time period, traditional free-weight training may be preferred.

One-year cessation following resistance training differently affects neuromuscular, body composition, and functional capacity in older adults

Cessation of resistance training could result in loss of the gains acquired. Therefore, the aim of the current study was to verify the effect of 1-year of detraining following resistance training on body composition, functional capacity, handgrip strength, localized muscular endurance, and countermovement jump performance (CMJ) in older adults. Fifteen participants (4 women and 11 men; 65.5 ± 4.3 years) completed all the procedures over the experimental period. The participants were followed up during a 9-week resistance training program and after 1-year detraining. Measurements included body composition, handgrip strength, localized muscular endurance, stair ascent and descent, timed up-and-go, and CMJ. The resistance training resulted in improvements in skeletal muscle mass, stair ascent and descent, handgrip strength, localized muscular endurance, and CMJ variables. After the detraining period, significant reductions were observed in skeletal muscle mass (Δ = − 0.92 ± 0.58 kg) and CMJ height, velocity, and impulse (Δ = − 3.03 ± 1.83 cm, − 0.063 ± 0.042 m/s, − 6.34 ± 8.49 N·s, respectively) compared to the post-training period, returning to the baseline values. Conversely, stair ascent and descent, handgrip strength, and localized muscular endurance did not differ after the detraining period (p > 0.05). Retention of functional capacity, localized muscular endurance, and handgrip strength improvements were observed. However, skeletal muscle mass and CMJ variables decreased after the detraining period.

Does Pain Neuroscience Education and Cognition-Targeted Motor Control Training Improve Cervical Motor Output? Secondary Analysis of a Randomized Clinical Trial.

In the context of interventions aimed at reducing pain, disability, and maladaptive pain cognitions in chronic neck pain, it is hypothesized that patients who have greater symptom reduction possibly also demonstrate greater improvement in cervical motor output. Therefore, the aim of this study was to examine the effect of pain neuroscience education plus cognition-targeted motor control training on cervical motor output. Impairments in cervical motor output were measured in 64 subjects with chronic neck pain using standardized tests. Cervical muscle strength, cervical mobility, balance, and cervical neuromuscular control were derived. To assess the differences between groups in response to treatment, a random-intercept linear mixed-models analysis, applying a diagonal covariance matrix, was used. A significant treatment × time interaction effect was found for neuromuscular control of the deep cervical flexors, favoring the experimental treatment at 3months' follow-up (mean group difference: 1.982; 95% confidence interval 0.779, 3.185; large effect size d=0.82). Significant main effects of time were found for the neuromuscular capacity of scapulothoracic muscles and for cervical mobility. No significant effects were found for balance, cervical muscle strength, or endurance of cervical flexors. Pain neuroscience education combined with cognition-targeted motor control training is not more effective than biomedically focused education and exercise therapy for improving cervical motor output in people with chronic neck pain. Our findings question the relative importance of factors such as pain, disability, and maladaptive pain cognitions on cervical motor output and the need to address it in treatment.

The correlation between jump height and mechanical power in a countermovement jump is artificially inflated

ABSTRACT The countermovement jump is commonly used to assess an athlete’s neuromuscular capacity. The aim of this study was to identify the mechanism behind the strong correlation between jump height and mechanical power in a countermovement jump. Three athletes each performed between 47 and 60 maximal-effort countermovement jumps on a force platform. For all three athletes, peak mechanical power and average mechanical power were strongly correlated with jump height (r = 0.54–0.90). The correlation between jump height and peak power was largely determined by the correlation between jump height and the velocity at peak power (r = 0.83–0.94) and was not related to the correlation between jump height and the ground reaction force at peak power (r = −0.20–0.18). These results confirm that the strong correlation between jump height and power is an artefact arising from how power is calculated. Power is a compound variable calculated from the product of instantaneous ground reaction force and instantaneous velocity, and application of statistical theory shows that the correlation between jump height and power is artificially inflated by the near-perfect correlation between jump height and the velocity at peak power. Despite this finding, mechanical power might still be useful in assessing the neuromuscular capacity of an athlete.

Spinal cord injury in infancy: activity-based therapy impact on health, function, and quality of life in chronic injury

IntroductionSpinal cord injury (SCI) in infancy magnifies the complexity of a devastating diagnosis. Children injured so young have high incidences of scoliosis, hip dysplasia, and respiratory complications leading to poor health and outcomes. We report the medical history, progression of rehabilitation, usual care and activity-based therapy, and outcomes for a child injured in infancy. Activity-based therapy (ABT) aims to activate the neuromuscular system above and below the lesion through daily, task-specific training to improve the neuromuscular capacity, and outcomes for children with acquired SCI.Case presentationA 3-month-old infant suffered a cervical SCI from a surgical complication with resultant tetraplegia. Until age 3, her medical complications included scoliosis, kyphosis, and pneumonia. Even with extensive physical and occupational therapy, she was fully dependent on caregivers for mobility and unable to roll, come to sit, sit, stand or walk. She initiated ABT at ~3 years old, participating for 8 months. The child’s overall neuromuscular capacity improved significantly, especially for head and trunk control, contributing to major advances in respiratory health, novel engagement with her environment, and improved physical abilities.DiscussionFrom injury during infancy until 3 years old, this child’s health, abilities, and complications were consistent with the predicted path of early-onset SCI. Due to her age at injury, severity and chronicity of injury, she demonstrated unexpected, meaningful changes in her neuromuscular capacity during and post-ABT associated with improved health, function and quality of life for herself and her caregivers.

Muscle loss in elderly patients - prevention effects of a multimodal therapy program for low back pain

Muscle loss with an increasing loss of muscle mass, muscle strength and muscle function is a disease in elderly individuals. Along with the severity of muscle loss, an increased frailty is evident. The consequences of an increased frailty are age-related reduced resilience and reduced strength conditions, and following this substantial loss of quality of life. The onset and progression of aging processes can be positively influenced by physical training, which helps to prevent the decline in neuromuscular capacity. There is consensus that hypertrophy training focusing on the training of situation specific movement tasks of the individual muscle groups is recommended. In this study we demonstrated that multimodal therapy is an efficient alternative intervention to strengthen the back muscles and by this to increase muscle growth in the areas of extension and flexion as well as lateralization and rotation on both sides. 52 patients aged between 50 and 65 with a main diagnosis of back disease were examined prospective. They completed a 3-week inpatient multimodal therapy program. Effects of the program were assessed by applying two isometric strength measurements of the back muscles. Baseline measurement (T0) was done on the first day of the program and post measurement (T1) on the last day of therapy. The results were described by means of SPSS as mean (M) and standard deviation (SD). The normal distribution was verified (Kolmogorov-Smirnov test). Data indicates that there are significant improvements in extension force, right lateral and right rotation force. Strength gains in flexion, left lateral and left rotation could also be demonstrated, but compared to the other three directions with reduced strength. It could be shown that even a multimodal therapy program leads to an increase in strength. Since pure hypertrophy training is a great challenge, especially for the elderly, the multimodal therapy concepts promising approach to facilitate the often difficult start to the treatment of muscle loss. The significant higher power increase concerning extension, rotation and lateralization on the right side compared to the left side is remarkable. Here further research is needed to obtain explanations. A significant weakness of the study is the lack of a control group. Further research with more sophisticated study designs (e.g. RCT) is necessary in order to learn more about this alternative intervention to treat muscle loss.

Effects of Adding Vertical or Horizontal Force-Vector Exercises to In-season General Strength Training on Jumping and Sprinting Performance of Youth Football Players.

Abade, E, Silva, N, Ferreira, R, Baptista, J, Gonçalves, B, Osório, S, and Viana, JL. Effects of adding vertical or horizontal force-vector exercises to in-season general strength training on jumping and sprinting performance of youth football players. J Strength Cond Res 35(10): 2769-2774, 2021-Football is characterized by short-term high-intensity triaxial activities that require optimized neuromuscular capacity. Thus, training routines must consider the direction of force application, particularly when strength exercises are performed. This study aimed to explore the effects of adding vertical or horizontal force-vector exercises to a 20-week in-season general strength training program on jumping and sprinting performance of youth football players. Twenty-four well-trained male under-17 players participated in this study and were randomly assigned to a control, vertical, or horizontal training group. Control group performed a general strength training program (free weights, eccentric-overload, and body mass exercises) once a week during 20 weeks. Vertical and horizontal groups additionally performed back-half-squat or barbell hip-thrust, respectively. Vertical group improved vertical jump (VJ) (squat jump, likely 4.5; ±4.4% and countermovement jump, likely 4.9; ±4.1%), horizontal jump (HJ) (most likely 7.5; ±2.7%), and sprint (10 m, likely -1.6; ±2.0% and 20 m, very likely -3.3; ±1.6%). The horizontal group showed unclear results in VJ; however, large improvements were observed in HJ (most likely, 13.0; ±4.8%), 10 m and 20 m (very likely -3.0; ±1.8% and most likely -3.8; ±1.0%, respectively). Back-squat and hip-thrust showed an important transference effect to both jumping and sprinting performance. If considering the effects of back-squat on VJ, hip-thrust improved HJ and sprint to a greater extent. This study reinforces the importance of performing both vertical and horizontal force-vector exercises to enhance physical performance during football in-season, even when performed only once a week.

Activity-Based Therapy Targeting Neuromuscular Capacity After Pediatric-Onset Spinal Cord Injury.

Background: Activity-based therapies aim to improve neuromuscular capacity after spinal cord injury (SCI). Objective: The purpose of this prospective study was to report the impact of Activity-based Locomotor Training (AB-LT) on neuromuscular capacity in pediatric patients with SCI. Methods: Participants were enrolled for their first episode of AB-LT for a minimum of 60 daily, 1.5-hour sessions. The Segmental Assessment of Trunk Control (SATCo) and the Pediatric Neuromuscular Recovery Scale (Pediatric NRS) were assessed initially, every 20 sessions, and post 60 sessions. Results: Twenty-six consecutive patients, mean age 5 years (SD = 3), completed a mean 55 sessions (SD = 4) within 63 weekdays (SD = 9). The Pediatric NRS total score improved significantly, adjusted mean 11.4, from initial to post-60 sessions (p < .05) with an average adjusted evaluation-to-evaluation 3.7 change. SATCo scores improved significantly across 60 sessions, mean change 5.2, an estimated 1.7 change between evaluations (p < .05). Age at enrollment and chronicity had no effect; however, initial neuromuscular capacity scores were negatively correlated with change scores (p < .05). Conclusion: Sixty AB-LT sessions significantly improved trunk and neuromuscular capacity in children with SCI, regardless of age or chronicity at enrollment. Patients with lower initial scores made greater improvements than patients with higher initial neuromuscular capacity. Anecdotal parent reports of their child's functional change in the home and community highlight the synergy between quantitative change in neuromuscular capacity and meaningful, improved quality of life and the need for formal investigation of this relationship.

Validity and Reliability of a Novel Integrative Motor Performance Testing Course for Seniors: The "Agility Challenge for the Elderly (ACE)".

Background: Assessing traditional neuromuscular fall risk factors (i.e., balance, gait, strength) in the elderly has so far mainly been done independently. Functional and integrative testing approaches are scarce. The present study proposes an agility course for an integrative assessment of neuromuscular and also cardiocirculatory capacity in seniors – and tests its criterion validity and reliability.Methods: Thirty-six seniors (age: 69.0 ± 2.8 years; BMI: 25.4 ± 3.5 kg/m2; sex: 19 males/17 females; weekly physical activity: 9.4 ± 5.5 h) participated. They completed four trials of the Agility Challenge for the Elderly (ACE)-course in two sessions separated by 1 week. The course consists of three segments focusing on different agility aspects. Cardiovascular capacity was assessed by 6-min walk test (6MWT), neuromuscular capacity by static, dynamic and perturbed standing balance tasks, habitual gait speed assessment, and rate of torque development testing. Parameters’ predictive strength for the ACE performance was assessed by regression analysis. Reliability was calculated with intraclass correlation coefficients and coefficients of variation.Results: Men completed the course in 43.0 ± 5.7 s and women in 51.9 ± 4.0 s. Overall and split times were explained by 6MWT time ( = 0.38–0.44), gait speed ( = 0.29–0.43), and to a lesser extent trunk rotation explosive strength ( = 0.05–0.12). Static and dynamic balance as well as plantar flexion strength explained the performance in some segments to a very small extent ( = 0.06–0.08). Good between- and within-day reliability were observed for total course and split times: The ICC for the between-day comparison was 0.93 (0.88–0.96) and ranged between 0.84 and 0.94 for split times. The within-day ICC was 0.94 (0.91–0.97) for overall time and 0.92–0.97 for split times. Coefficients of variation were smaller than 5.7% for within and between day analyses.Conclusion: The ACE course reflects cardiocirculatory and neuromuscular capacity, with the three ACE segments potentially reflecting slightly different domains of neuromuscular (static and dynamic balance, ankle, and trunk strength) performance, whereas cardiocirculatory fitness and gait speed contribute to all segments. Our test can detect changes in overall performance greater than 5.7% and can thus be useful for documenting changes due to interventions in seniors.

MAXIMAL MUSCULAR STRENGTH AS A PREDICTOR OF OPTIMUM DROP HEIGHT

The first goal of the study was to examine the relationship between maximum muscle strength and optimal drop height (DHopt), while the second goal was to examine the relationship between regression models for the prediction of DHopt and DHopt determined by variable H. A total of 30 respondents, students of the Faculty of Sport and Physical Education participated in the experiment. During the experiment, eight altitudes were randomized in the range of 0.12 to 0.82 m. The instruction was to achieve a higher jump, with a shorter duration of rebound. A positive statistically significant correlation between DHopt determined by prediction method with 1 RM / BW 0.67 and MDS (p<0.05) was calculated. When computing the DHopt connection determined by the dialing method with the maximum muscle strength of the subjects, no statistically significant correlation was obtained, but there is a positive trend. Determined by the prediction method DHopt is (0.47±0.17 m) and using the regression model with 1 RM/BW 0.67 (0.47±0.07 m) and with MDS (0.48±0.06 m). In order to explain high relationship between models, it should be noted that the muscles of knee joint have a more important role in motor tasks performed at higher intensity like during drop jump. With this in mind, DHopt in the jumping jump can be determined depending on the neuromuscular capacity to generate the maximum muscle strength of the knee of the knee in order to use the optimal intensity within the pliometric training.