Examining Unilateral and Bilateral Exercises through the Load-velocity Relationship.

This study aimed to examine the load-velocity (L-V) relationship in the bench-press (BP) and leg-press (LP) exercises performed unilaterally, and compared this unilateral L-V relationship with the bilateral variants. Nineteen men (age=23.5±2.1 years) completed two incremental tests in BP and LP, performed bilaterally and unilaterally, across two sessions with a 48-hour rest period. We found a close relationship between medium propulsive velocity (MPV) and %1RM in unilateral BP (R2 =0.97, SEE=0.06 m·s-1) and LP (R2=0.96, SEE=0.06 m·s-1). No significant differences were observed between the preferred and non-preferred sides in the L-V relationship for either exercise. Additionally, higher velocities were achieved in unilateral exercises compared to bilateral exercises, particularly with light and moderate loads (30-70%1RM) in BP (p<0.05) and with light loads (30-45%1RM) in LP (p<0.05). Close L-V relationships were observed in unilateral exercises, without differences in the L-V relationships between preferred and non-preferred sides despite the interlimb asymmetries in the absolute strength values. Interestingly, lower velocities were observed at light loads (~30-45% 1RM) for bilateral compared to unilateral exercises, which could be explained by different strength deficits for these exercises.

Inter-repetition Rest Impact on Percentage of Repetition Completed at Certain Velocity Loss.

This study examined the impact of different inter-repetition rest (IRR) configurations (zero seconds [IRR0], three seconds [IRR3], and self-selected less than five seconds [SSIRR]) on estimating the number of repetitions (Nrep) and the percentage of completed repetitions relative to the maximum number of repetitions possible to failure (%rep) after reaching 10%, 20%, and 30% velocity loss thresholds (VLT). Eighteen men completed three sessions, each with a different IRR configuration, separated by 48-72 hours. Single sets of repetitions to momentary muscular failure were performed against 65%, 75%, and 85% of the one-repetition maximum during free-weight back squat and bench press exercises. No significant differences were reported between IRR configurations for the Nrep (P≥0.089) and %rep (P≥0.061), except for %rep after reaching the 20-30%VLT against 65%1RM and the 10-20%VLT against 75%1RM in the bench press exercise (P≤0.048). Additionally, both Nrep and %rep exhibited high interindividual variability (between-subject CV=14-79%) across the different IRR configurations. The individual %rep-%VLT relationships were slightly stronger than the general %rep-%VLT relationships (median R 2 =0.914-0.971 vs. 0.698-0.900). Overall, regardless of the IRR configuration, this novel velocity-based approach does not guarantee the same effort levels across subjects in the free-weight back squat and bench press sets.

Match and Training High Intensity Activity-Demands Profile During a Competitive Mesocycle in Youth Elite Soccer Players.

The monitoring of the high intensity activity-demands profile during official matches (OMs) and training sessions (TSs) provides a deeper understanding of the relationship between training and competition loads as well as players' fitness characteristics. The aims of this study were to: 1) describe the training and match high intensity activity-demands profile in U-19 soccer players; 2) compare the profile depending on the type of session (OM or TS) throughout match-weeks; and 3) differentiate between profiles depending on the match location (home or away). Twenty-five U-19 Spanish soccer players were monitored during TSs and OMs for a one-month competitive period using a WIMU PROTM wearable inertial device. The variables of the study were: high speed running distance (HSRD), total sprints (SPs), maximum speed (MS) and player load (PL). OMs required higher demands than TSs in HSRD (460.99 ± 206.18 vs. 315.45 ± 180.12 m; p < 0.01; d = 0.75), SPs (10.86 ± 6.64 vs. 7.23 ± 4.82; p < 0.01; d = 0.69), MS (29.99 ± 2.54 vs. 28.50 ± 2.4 km/h; p < 0.01; d = 0.59) and PL (103.08 ± 24.15 vs. 83.18 ± 17.96 a.u.; p < 0.01; d = 0.94). The interaction between the type of session and mean week's demands presented differences with medium effect size in MS (p < 0.01; ωp 2 = 0.06) and small effect size in HSRD (p = 0.04; ωp 2 = 0.03), and SP (p = 0.05; ωp 2 = 0.03), but there were no differences in PL (p = 0.18; ωp 2 = 0). Finally, no differences were found in the match location comparison (p > 0.33; d = 0.22-0.33). Therefore, the profiles presented could be useful for future scientific purposes and serve as valid information for coaches trying to optimize performance.

Intervención con un Programa de Ejercicio Físico en la empresa / Intervention through a physical exercise program at the company

FUNDAMENTOS: Existen evidencias sobre los beneficios que conlleva la participación en Programas de Ejercicio Físico (PEF) en la empresa y por ello es importante que la participación en un PEF sea la mayor posible. El objetivo de este trabajo es hacer un estudio piloto que pueda dar información sobre el perfil de los trabajadores que participan y de los que no participan en un PEF en la empresa. MÉTODOS: Se han utilizado los cuestionarios validados SF-36 de calidad de vida; PSS de estrés percibido; cuestionario de autoestima más una serie de datos demográficos seleccionados. Han sido contestados por los trabajadores de una empresa que realizaba un PEF en el que participaban 17 trabajadores de 42 que forman la plantilla. El tamaño muestral es n=31. La participación ha sido voluntaria. La fuente de información son los trabajadores de esta empresa. Se ha realizado un estudio descriptivo transversal. RESULTADOS: en el grupo de trabajadores que no participaban en el PEF se encontró que la mayoría tienen un contrato de duración limitada (resultado que obtuvo significación estadística), menor nivel de estrés en el cuestionario PSS, mayor nivel de autoestima en el cuestionario de autoestima y/o en el rol físico del cuestionario SF-36; tienen una mejor percepción de salud respecto del otro grupo. CONCLUSIONES: a través de estudios posteriores se podría investigar la relación entre estos perfiles y la participación en PEF de entrenamiento físico en la empresa, para que la implantación de un PEF sea exitosa

OBJECTIVES: There is evidence of the benefits gained by participating in the Physical Exercise Program (PEP) in the company. The objective of this investigation is to describe the profile of employees who take part and that of employees who do not take part in the PEP. METHODS: We used validated questionnaires, the Short Form-36 Health Survey (SF-36); PSS (stress scale perceived); self-esteem questionnaire and a series of selected demographic data. They were answered by the workers of a company who were on a PEP; 17 out of 42 who formed the workforce were participating on it. The sample size is n=31. Participation was voluntary. The source of information is the employees of the company. We performed a cross sectional study. RESULTS: we found out that most of the workers not involved in the PEP have a fixed-term contract whose result brought statistical significance in showing less stress level in the PSS questionnaire, higher self-esteem in the questionnaire of self-esteem and/or the physical role of the SF-36; they have a better perception of health compared to the other group. CONCLUSIONS: through further studies could investigate the relationship between these profiles and the participation or non- participation in a PEP in the work place, to develop effective strategies to encourage workers to participate in PEP in the work place