Both Isometric and Dynamic Testing Are Essential for a Comprehensive Assessment of the Knee Extensors.

Grossio, L, Salvaggio, F, Brustio, PR, Rainoldi, A, Samozino, P, and Boccia, G. Both isometric and dynamic testing are essential for a comprehensive assessment of the knee extensors. J Strength Cond Res XX(X): 000-000, 2025-The improvements of measurement tools and data analysis enhanced our possibilities to assess neuromuscular performance, but also created confusion regarding significance and practical applications of this available information.

Mathematical modeling of a force-velocity-position relationship in vertical jump.

This study aimed to evaluate whether combining force-velocity Fv and force-position Fp models, originally developed for single-joint movements, could effectively characterize force production during the push-off phase of a vertical jump. Six force-velocity-position Fv,p models, integrating three Fv (Anderson, Hill, and Linear) and two Fp (Cosine and Quadratic) models were assessed. Fifteen trained CrossFit athletes performed maximal countermovement jumps under varying loads and push-off depths with ground reaction forces recorded via force plates.

Sex differences in the rate of torque development and torque-velocity relationship are due to maximal strength only.

Purpose: This study aimed to analyse the sex differences in the rate of torque development (RTD) and torque-velocity parameters with and without normalisation for maximal voluntary torque (MVT).

Methods: Right-leg knee extensors were tested in 64 healthy and active participants (31 F and 33 M). MVT and RTD were obtained under isometric conditions.

Force-velocity and power-velocity relationships in on-water rowing.

Force-velocity (FV) relationships are used to evaluate athletes and individualise training in several tasks. In rowing, only one previous study has determined FV relationships using ergometers. This study aimed to develop a method to obtain FV relationships during on-water rowing, to assess their quality and inter-day reliability and to compare them with ergometer profiles.

The Rate of Torque Development as a Determinant of the Torque-Velocity Relationship.

We investigate the contribution of isometric rate of torque development (RTD) and maximal voluntary torque (MVT) to the dynamic force production capacities of knee extensors obtained from the torque-velocity (TV) relationship, that is, the theoretical maximal velocity (V), torque (T), and maximal power (P). Single-leg knee extensors were tested in 64 young adults (31 females). RTD and root mean square (RMS) of electromyographic signals from the knee extensors were recorded during isometric and incremental load dynamic (nonisokinetic) contractions.

Ankle supports enhance only psychological aspects of the Ankle-GO score in patients with chronic ankle instability.

CONTEXT: Chronic ankle instability (CAI) is the most serious long-term complication following an ankle sprain. Taping and bracing are frequently employed in the return to sport (RTS) continuum to avoid injury recurrence and to maximize post-injury performance. The Ankle-GO score is a valid and reliable objective RTS criteria, but the influence of ankle supports on this score in CAI patients remains unknown.

An Instrument for Evaluating the Self: The Self-Discrepancies Scale in Non-Clinical Participants.

Objective: The Self-Discrepancies Scale (S-DS) is a multiple-subscore instrument designed to assess discrepancies between mental representations of the self: the actual self on one hand, and the ideal and socially prescribed selves on the other. Its idiographic subscores rely on the endorsement of self-descriptive traits, while its abstract subscores form an overall judgement of felt self-discrepancies. The objectives of the present study were to (i) evaluate the S-DS in a new non-clinical population, (ii) expand the body of data on the S-DS's convergent validity, (iii) study the idiographic data for the S-DS, and (iv) establish a nomothetic list of traits with a better choice of unwanted traits.

Reliability of isokinetic dynamometer for isometric assessment of ankle plantar flexor strength.

Objective: To evaluate isokinetic dynamometer reliability for isometric assessment of plantar flexor (PF) strength.

Design: Cross-sectional.

Setting: Testing by the same physiotherapist twice during a first session (repeatability) and once during a second session (reproducibility).

Impaired physical ability in patients with transfusion-dependent β-thalassaemia: Can regular physical activity be a countermeasure?

Transfusion-dependent β-thalassaemia (TDβT) is a genetic disorder characterised by reduced or absent β-globin chain synthesis, resulting in chronic anaemia. Treatment consists of regular blood transfusions and chelation therapy to limit iron overload and its negative effects on organs (e.g.

Executive functions disorders in children with frontal and temporal epilepsy.

Introduction: Children with focal epilepsy often present with executive functions (EFs) deficits. EFs deficits can contribute to adaptive challenges and have a negative impact on academic achievement. The purpose of this study was to investigate the EFs profiles of children diagnosed with frontal lobe epilepsy or temporal lobe epilepsy.

Impaired Symmetry in Single-Leg Vertical Jump and Drop Jump Performance 7 Months After ACL Reconstruction.

Background: Anterior cruciate ligament reconstruction (ACLR) continues to be associated with a variable rate of return to sports and a concerning rate of further anterior cruciate ligament injury. Persistent functional deficits may explain these results and support the need to keep exploring lower limb functional indexes, especially during vertical jumping. This would help improve rehabilitation through the return-to-sports continuum and improve postoperative outcomes.

Testing the predictive capacity of a muscle fatigue model on electrically stimulated adductor pollicis.

Purpose: Based on the critical power (P or critical force; F) concept, a recent mathematical model formalised the proportional link between the decrease in maximal capacities during fatiguing exercises and the amount of impulse accumulated above F. This study aimed to provide experimental support to this mathematical model of muscle fatigability in the severe domain through testing (i) the model identifiability using non-exhausting tests and (ii) the model ability to predict time to exhaustion (t) and maximal force (F) decrease.

Methods: The model was tested on eight participants using electrically stimulated adductor pollicis muscle force.

[Preventing decline of autonomy through the promotion of mental health: a randomized clinical trial for older adults with disabilities].

Among older adults with disabilities, maintaining active aging can often be compromised. However, the literature highlights a positive link between mental health and autonomy on one hand, and self-determined motivation on the other. Therefore, self-determined motivation may be improved by promoting mental health and, in the end, older adults autonomy.

Implementation of a Primary Prevention Program for Posttraumatic Stress Disorder in a Cohort of Professional Soldiers (PREPAR): Protocol for a Randomized Controlled Trial.

Background: Posttraumatic stress disorder (PTSD) is a psychiatric disorder that can manifest after a traumatic event where the individual perceives a threat to his or her life or that of others. Its estimated prevalence in the European population is 0.7% to 1.

Comparison of neuromuscular fatigability amplitude and etiologies between fatigued and non-fatigued cancer patients.

Purpose: Cancer-related fatigue (CRF) is the most reported side effect of cancer and its treatments. Mechanisms of CRF are multidimensional, including neuromuscular alterations leading to decreased muscle strength and endurance (i.e.

A New Way to Restrict Free Leg Movement During Unilateral Vertical Jump Test.

The purpose of this investigation was (1) to test the effect of movement restriction of the free leg during unilateral vertical jump on performance and power output comparing 2 different jump techniques: flexed (Classic technique) and straight (FC Luzern technique) free leg, and (2) to test the correlation between performance and power output obtained using these 2 techniques. Twenty elite soccer players performed squat (SJ) and countermovement (CMJ) jumps on each leg. The jump height and peak power output were compared between the 2 techniques for both legs.

Exploring the Low Force-High Velocity Domain of the Force-Velocity Relationship in Acyclic Lower-Limb Extensions.

Purpose: To compare linear and curvilinear models describing the force-velocity relationship obtained in lower-limb acyclic extensions, considering experimental data on an unprecedented range of velocity conditions.

Methods: Nine athletes performed lower-limb extensions on a leg-press ergometer, designed to provide a very broad range of force and velocity conditions. Previously inaccessible low inertial and resistive conditions were achieved by performing extensions horizontally and with assistance.

Reliability and validity of 2D-video analysis to objectively assess hamstring performance during the H-test.

The H-test is commonly used during return-to-sport decisions after hamstring muscle injury. The primary aim was to evaluate the reliability of two-dimensional (2D) video analysis for the H-Test. The second aim was to assess its validity compared to an electronic gyroscope (gold standard), and the third aim was to establish normative values.

Relaxing effects of music and odors on physiological recovery after cognitive stress and unexpected absence of multisensory benefit.

Several studies have described, often separately, the relaxing effects of music or odor on the autonomic nervous system (ANS) activity. Only a few studies compared the presentation of these stimuli and their interaction within a same experimental protocol. Here, we examined whether relaxing music (slow-paced classical pieces) and odor (lavender essential oil) either presented in isolation or in combination would facilitate physiological recovery after cognitive stress.

Sprint Acceleration Mechanical Outputs Derived from Position- or Velocity-Time Data: A Multi-System Comparison Study.

To directly compare five commonly used on-field systems (motorized linear encoder, laser, radar, global positioning system, and timing gates) during sprint acceleration to (i) measure velocity−time data, (ii) compute the main associated force−velocity variables, and (iii) assess their respective inter-trial reliability. Eighteen participants performed three 40 m sprints, during which five systems were used to simultaneously and separately record the body center of the mass horizontal position or velocity over time. Horizontal force−velocity mechanical outputs for the two best trials were computed following an inverse dynamic model and based on an exponential fitting of the position- or velocity-time data.

Effects of Repeated Sprint Training With Progressive Elastic Resistance on Sprint Performance and Anterior-Posterior Force Production in Elite Young Soccer Players.

Le Scouarnec, J, Samozino, P, Andrieu, B, Thubin, T, Morin, JB, and Favier, FB. Effects of repeated sprint training with progressive elastic resistance on sprint performance and anterior-posterior force production in elite young soccer players. J Strength Cond Res 36(6): 1675-1681, 2022-This study aimed to determine whether repeated sprint training with progressive high elastic resistance could improve sprint performance and anterior-posterior (AP) force production capacities of elite young soccer players.