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Abstract Background Pandemic type A (H1N1) influenza arose in early 2009, probably in Mexico and the United States, and reappeared in North America in September for seven more months. An amino acid substitution in the hemagglutinin (HA), D222G, has been reported in a significant proportion of patients with a severe and fatal outcome. We studied the prevalence of HA222 substitutions in patients in Mexico during the second wave and its association with clinical outcome and pathogenicity in a mouse model. Methods The nucleotide sequences of hemagglutinin (HA) from viruses collected from 77 patients were determined including 50 severe and fatal cases and 27 ambulatory cases. Deep sequencing was done on 5 samples from severe or fatal cases in order to determine the quasispecies proportion. Weight loss and mortality due to infection with cultured influenza viruses were analyzed in a mouse model. Results Viruses from 14 out of 50 hospitalized patients (28%) had a non aspartic acid residue at the HA 222 position (nD222), while all 27 ambulatory patients had D222 (p = 0.0014). G222 was detected as sole species or in coexistence with N222 and D222 in 12 patients with severe disease including 8 who died. N222 in coexistence with D222 was detected in 1 patient who died and co-occurrence of A222 and V222, together with D222, was detected in another patient who died. The patients with a nD222 residue had higher mortality (71.4%), compared to the group with only D222 (22.2%, p = 0.0008). Four of the 14 viruses from hospitalized patients were cultured and intranasally infected into mice. Two viruses with G222 were lethal while a third virus, with G222, caused only mild illness in mice similar to the fourth virus that contained D222. Conclusions We confirm the elevated incidence of HA222 (H1N1)pdm09 variants in severe disease and mortality. Both clinical and mouse infection data support the idea that nD222 mutations contribute to increased severity of disease but additional determinants in disease outcome may be present.

Abstract Background Institutionalized older persons have a poor functional capacity. Including physical exercise in their routine activities decreases their frailty and improves their quality of life. Whole-body vibration (WBV) training is a type of exercise that seems beneficial in frail older persons to improve their functional mobility, but the evidence is inconclusive. This trial will compare the results of exercise with WBV and exercise without WBV in improving body balance, muscle performance and fall prevention in institutionalized older persons. Methods/Design An open, multicentre and parallel randomized clinical trial with blinded assessment. 160 nursing home residents aged over 65 years and of both sexes will be identified to participate in the study. Participants will be centrally randomised and allocated to interventions (vibration or exercise group) by telephone. The vibration group will perform static/dynamic exercises (balance and resistance training) on a vibratory platform (Frequency: 30-35 Hz; Amplitude: 2-4 mm) over a six-week training period (3 sessions/week). The exercise group will perform the same exercise protocol but without a vibration stimuli platform. The primary outcome measure is the static/dynamic body balance. Secondary outcomes are muscle strength and, number of new falls. Follow-up measurements will be collected at 6 weeks and at 6 months after randomization. Efficacy will be analysed on an intention-to-treat (ITT) basis and 'per protocol'. The effects of the intervention will be evaluated using the "t" test, Mann-Witney test, or Chi-square test, depending on the type of outcome. The final analysis will be performed 6 weeks and 6 months after randomization. Discussion This study will help to clarify whether WBV training improves body balance, gait mobility and muscle strength in frail older persons living in nursing homes. As far as we know, this will be the first study to evaluate the efficacy of WBV for the prevention of falls. Trial Registration ClinicalTrials.gov: NCT01375790

Background: The global inequity in the distribution of COVID-19 vaccines underscores the urgent need for innovative and cost-effective vaccine technologies to address access disparities and implement local manufacturing capabilities. This is essential for achieving and sustaining widespread immunity, and for ensuring timely protection of vulnerable populations during future booster campaigns in lower- middle income countries (LMICs)., Methods: To address this need, we conducted a phase II clinical trial to evaluate the safety and immunogenicity of the locally manufactured AVX/COVID-12 "Patria" (AVX) vaccine as a booster dose. The vaccine was administered either intramuscularly (IM) or intranasally (IN) to participants who had previously completed a vaccination regimen for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using adenoviral vector, inactivated virus, or mRNA-based vaccines. Participants with initial anti-spike IgG titers below 1,200 U/mL were included, allowing us to observe the booster effect induced by vaccination., Results: Both IM and IN immunization with AVX were found to be safe and well-tolerated. The vaccine induced a significant (>2.5-fold) increase in neutralizing antibodies against the ancestral Wuhan strain and variants of concern (VOCs), including Alpha, Beta, Delta, and Omicron (BA.2 and BA.5). This immune response was further supported by increased cellular production of interferon-gamma (IFN-γ), demonstrating a robust and multifaceted immune reaction., Conclusions: The administration of AVX as a booster dose, whether through IM or IN routes, was safe and well-tolerated. The vaccine extended immune responses not only against the ancestral Wuhan-1 strain but also against various VOCs. Its ability to enhance preexisting immune responses suggests a potential contribution to expanding and sustaining herd immunity within the population., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Laboratorios Avimex S.A. de C.V. reports financial support was provided by Consejo Nacional de Humanidades, Ciencia y Tecnología. México. Bernardo Lozano-Dubernard reports financial support was provided by Laboratorios Avimex S.A. de C.V. P.P., F.K., and A.G.-S. has patent #62/994,252 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/018,457 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/020,503 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/024,436 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/251,020 pending to Mount Sinai. M.T., D.S.-M., C.L.-M., H.E.C.-C., F.C.-P., G.P.D.L., and B.L.-D. has patent #PCT/IB2022/058886. MX/a/2021/011439 pending to Avimex S.A. de C.V. The vaccine candidate administered in this study was developed by faculty members at the Icahn School of Medicine at Mount Sinai including P.P., F.K., and A.G.-S. Mount Sinai is seeking to commercialize this vaccine; therefore, the institution and its faculty inventors could benefit financially. The Icahn School of Medicine at Mount Sinai has filed patent applications relating to SARS-849 CoV-2 serological assays (USA Provisional Application Numbers: 62/994,252, 63/018,457, 63/020,503, and 63/024,436) and NDV-based SARS-CoV-2 vaccines (USA Provisional Application Number: 63/251,020) which list F.K. as co-inventor. A.G.-S. and P.P. are co-inventors in the NDV-based SARS-CoV-2 vaccine patent application. Patent applications were submitted by the Icahn School of Medicine at Mount Sinai. Mount Sinai has spun out a company, Kantaro, to market serological tests for SARS-CoV-2 and another company, CastleVax, to commercialize SARS-CoV-2 vaccines. F.K., P.P., and A.G.-S. serve on the scientific advisory board of CastleVax and are listed as co-founders of the company. F.K. has consulted for Merck, Seqirus, Curevac, and Pfizer, and is currently consulting for Gritstone, Third Rock Ventures, GSK, and Avimex. The F.K. laboratory has been collaborating with Pfizer on animal models of SARS-CoV-2. C.L.-M. has consulted for AstraZeneca. The A.G.-S. laboratory has received research support from GSK, Pfizer, Senhwa Biosciences, Kenall Manufacturing, Blade Therapeutics, Avimex, Johnson & Johnson, Dynavax, 7Hills Pharma, Pharmamar, ImmunityBio, Accurius, Nanocomposix, Hexamer, N-fold LLC, Model Medicines, Atea Pharma, Applied Biological Laboratories, and Merck. A.G.-S. has consulting agreements for the following companies involving cash and/or stock: Amovir, Vivaldi Biosciences, Contrafect, 7Hills Pharma, Avimex, Pagoda, Accurius, Esperovax, Farmak, Applied Biological Laboratories, Pharmamar, CureLab Oncology, CureLab Veterinary, Synairgen, Paratus, Pfizer, and Prosetta. A.G.-S. has been an invited speaker in meeting events organized by Seqirus, Janssen, Abbott, and AstraZeneca. PP has a consulting agreement with Avimex. Members of Avimex developed the live vaccine used in this study. Avimex filed patent applications with Mount Sinai and CONAHCYT. M.T., D.S.-M., C.L.-M., H.E.C.-C., F.C.-P., G.P.D.L., and B.L.-D. are named as inventors on at least one of those patent applications. The clinical study was entirely performed in Mexico, and Mount Sinai had no role in it. The rest of the participants are employees of their corresponding institutions and declare no competing interests. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The relationships between asymmetries and performance or the identification of the asymmetry profile that has been routinely studied during jumping tests are largely derived from male-only and small sample size studies. Therefore, the aims of this study were: 1) to evaluate the magnitude and the direction of jump asymmetries (vertical and lateral) in three different age groups of adolescent female handball players, and 2) to identify the effect of asymmetry between limbs on jump performance in the three age groups. One hundred and eighty-five adolescent female handball players (age: 14.88 ± 1.49 years) were distributed in three groups: U14, U16 and U18 and performed two tests to assess jumping ability which were the single leg countermovement jump (SL-CMJ) and the single leg hop lateral (SL-HL). The magnitude of asymmetry in the SL-CMJ test (10.80%) was higher compared to that of the SL-LH test (6.47%), and there were no significant differences between particular categories. The direction of asymmetry represented by the Kappa values showed "poor" and "fair" levels of agreement in U14 and U16 categories, which means that asymmetries rarely favored the same side during each jumping test, but in contrast, in the U18 category the Kappa value result was "slight". There were significant correlations between SL-CMJ jumping asymmetries and jumping performance in the U18 category (r = 0.31 to 0.49). These data indicate that in order to identify the player's asymmetry profile, we need to consider the magnitude and the direction of different tests which will help better understand the natural deficits, contextualize them and consider appropriate training interventions for the reduction of inter-limb asymmetries., Competing Interests: The authors declare no conflict of interest., (Copyright: © Academy of Physical Education in Katowice.)

Purpose: Change of direction while dribbling appears to be of interest for on-court performance in basketball. The study aim was to assess the validity and reliability of the V-cut dribbling test (VcutBk) in young basketball players., Methods: Ninety-two young basketball players from 8 to 21 years old (74% male) were classified in relation to peak height velocity (PHV) offset. To examine validity and test-retest reliability, VcutBk was performed in 2 identical sessions separated by 1 week. Participants also performed the V-cut test and linear sprint test with and without dribbling to analyze correlations between tests in different somatic maturity stages., Results: The relationships of the VcutBk with the other tests and skill-time-related deficits were interpreted from large (r > .51) to very large (r > .71). The comparisons between pre-PHV and post-PHV groups of basketball players showed significant and large effect in the VcutBk (d = 2.04; mean difference = 2.59; 95% CI, 1.86 to 3.32). Also, significant main effects when comparing PHV groups were reported in all skill-time-related deficits (P < .001, ηp2=.13-.28, moderate to large effect size). Test-retest reliability and signal-to-noise ratio analysis did not show substantial between-trials differences in VcutBk. Reliability scores showed high intraclass correlation coefficient (.95) and low coefficient of variation (0.23%)., Conclusions: The VcutBk seems to be a valid and reliable test to assess change of direction while dribbling. VcutBk performance and skill-time-related deficits seem to be sensitive to somatic maturity. Basketball coaches should consider the VcutBk to assess young basketball players.

Abstract: Madruga-Parera, M, Bishop, C, Fort-Vanmeerhaeghe, A, Beato, M, Gonzalo-Skok, O, and Romero-Rodríguez, D. Effects of 8-weeks of Isoinertial vs. Cable-resistance Training on Motor Skills Performance and Interlimb Asymmetries. J Strength Cond Res 36(5): 1200-1208, 2022-The aim of this study was to compare the effects of 8 weeks of isoinertial vs. cable-resistance training on motor skills performance and interlimb asymmetries in handball players. Thirty-four young male handball players (mean ± SD: age: 15.96 ± 1.39 years; height: 1.74 ± 0.73 m; body mass: 70.5 ± 13.3 kg) participated in a randomized trial. The players performed an isoinertial program using a portable flywheel device or a cable-resistance device. Performance variations and interlimb asymmetries in dominant (D) and nondominant (ND) limb means of the unilateral countermovement jump (UCMJ), the unilateral lateral jump (ULJ), the unilateral broad jump (UBJ), handball throwing (HT), change of direction speed (COD180), the linear sprint (S20), the V-CUT test, and the repeated change of direction (RCOD) were recorded. Significant interactions were shown in RCODD (p = 0.003, ηp = 0.25), HT (p = 0.015, ηp = 0.17) and UCMJASY (p = 0.037, ηp = 0.13). Post-hoc testing revealed higher effect sizes in the isoinertial group (p < 0.05) for the performance improvements in RCODD (-1.35 large vs. -0.22, small) and HT (0.88, moderate vs. 0.00, trivial), in addition to interlimb asymmetry reductions in UCMJASY (-0.70 moderate vs. -0.32, small). Significant main effects of time in COD180, RCOD, UCMJ, and UBJ for both limbs (p < 0.05, from moderate to large effect size), and in ULJND (p < 0.001, large), UCMJASY (p < 0.001, moderate), V-CUT (p = 0.014, small), and HT (p = 0.015, large) were found. The effect sizes revealed greater magnitudes in the isoinertial group. In conclusion, although both resistance training programs improve players' to physical performance and reduce interlimb asymmetries, greater improvements were recorded with the isoinertial resistance training than with the cable-resistance methodology., (Copyright © 2020 National Strength and Conditioning Association.)

Mexico City has one of the highest incidences of acute lymphoblastic leukemia (ALL) globally, with patients showing low survival, and high relapse rates. To gain more insight into the molecular features of B-ALL in Mexican children, we isolated CD10 + /CD19 + precursor B lymphoblasts from four bone marrow and nine peripheral blood samples of B-ALL patients using a fluorescence-activated cell sorting protocol. The global gene expression profile (BM vs PB) revealed 136 differentially expressed genes; 62 were upregulated (45.6%) and 74 were downregulated (54.4%). Pearson's correlation coefficient was calculated to determine the similarity between pre-B lymphoblast populations. We selected 26 highly significant genes and validated 21 by RT-qPCR (CNN3, STON2, CALN1, RUNX2, GADD45A, CDC45, CDC20, PLK1, AIDA, HCK, LY86, GPR65, PIK3CG, LILRB2, IL7R, TCL1A, DOCK1, HIST1H3G, PTPN14, CD72, and NT5E). The gene set enrichment analysis of the total expression matrix and the ingenuity pathway analysis of the 136 differentially expressed genes showed that the cell cycle was altered in the bone marrow with four overexpressed genes (PLK1, CDC20, CDC45, and GADD45A) and a low expression of IL7R and PIK3CG, which are involved in B cell differentiation. A comparative bioinformatics analysis of 15 bone marrow and 10 peripheral blood samples from Hispanic B-ALL patients collected by the TARGET program, corroborated the genes observed, except for PIK3CG. We conclude the Mexican and the Hispanic B-ALL patients studied present common driver alterations and histotype-specific mutations that could facilitate risk stratification and diagnostic accuracy and serve as potential therapeutic targets., (© 2022. The Author(s).)

Deficits in hamstring muscle strength and in hip range of motion (ROM) have been considered risk factors for hamstring muscle injuries. However, there is a lack of information on how chronic exposure to regular football training affects hamstring muscle strength and hip ROM. The aim of this study was to examine the longitudinal effect of football training and competition during a complete season on hamstring muscle strength and hip ROM in football players. A total of 26 semi-professional football players underwent measurements of isometric hamstring muscle strength and passive hip flexion/extension, and internal/external hip rotation (IR/ER) ROM during the football season (pre-season, mid-season, end-season). Compared to pre-season, hamstring muscle strength increased in the dominant (+11.1%, p = 0.002) and non-dominant (+10.5%, p = 0.014) limbs in the mid-season. Compared to mid-season, hamstring strength decreased in the dominant (−9.3%, p = 0.034) limb at end-season. Compared to the pre-season, hip extension ROM decreased in mid-season in the dominant (−31.7%, p = 0.007) and non-dominant (−44.1%, p = 0.004) limbs, and further decreased at end-season (−49.0%, p = 0.006 and −68.0%, p < 0.001) for the dominant and non-dominant limbs. Interlimb asymmetry for hip IR ROM increased by 57.8% (p < 0.002) from pre-season to mid-season. In summary, while hamstring muscle strength increased during the first half of the football season in football players, a progressive reduction in hip extension ROM was observed throughout the season. The reduced hip extension ROM suggests a reduced mobility of the hip flexors, e.g., iliopsoas, produced by the continuous practice of football. Consequently, hip-specific stretching and conditioning exercises programs should be implemented during the football season.

The aim of this study is to investigate inter-tester and intra-tester reliability of a novel clam test (CLAMT) for the measurement of gluteal muscle strength and to detect possible differences between CLAMT values in football players with and without a history of groin injuries. Twenty male football players participated in the test-retest and sixty-two male professional football players participated in the case-control study. Hip abductor maximal muscle strength was evaluated either using CLAMT or in a supine position with the hip in a neutral pose. For CLAMT, intraclass correlation coefficient (ICC) for inter-tester-intra-day reliability was 0.80 (95% CI: 0.60-0.90), with a standard error of measurement of 34.2 N. The intra-tester-intra-day ICC was 0.92 (95% CI: 0.87-0.95), with a standard error of measurement of 23.6 N. The inter-week ICC was 0.96 (95% CI: 0.92-0.98), with a standard error of measurement of 18.9 N. CLAMT showed lower (but not significant) strength values in football players with a history of groin injuries to non-injured players. CLAMT showed good to excellent levels of reliability, intraday and inter-week, with low standard errors of measurement while it was effective ( possible ) to identify residual weakness in players with previous groin injuries.

Abstract: Madruga-Parera, M, Bishop, C, Beato, M, Fort-Vanmeerhaeghe, A, Gonzalo-Skok, O, and Romero-Rodríguez, D. Relationship between inter-limb asymmetries and speed and change of direction speed in youth handball players. J Strength Cond Res 35(12): 3482-3490, 2021-The aims of the present study were to quantify interlimb asymmetry from jumping, change of direction speed (CODS), and iso-inertial tests and to establish the association between those asymmetry scores and performance during speed and CODS tests in youth handball athletes. Twenty-six youth handball players (age: 16.2 ± 0.9 years) volunteered to participate in this study and performed single-leg countermovement jumps, single-leg broad jumps, single-leg lateral jumps, CODS tests at 180° (CODS180) and 90° (CODS90), change of direction actions with iso-inertial overload (crossover step [CRO] and lateral shuffle step), and a 20-m sprint test. Excellent intraclass correlation coefficient (ICC) values were found for all tests (ICC = 0.96-1.00) with the exception of the dominant limb during the CODS90 test (ICC = 0.69). Interlimb asymmetry scores ranged from 3.66 to 12.67%. Iso-inertial asymmetry values were higher than those found during jumping tasks (9.8-12.7% vs. 3.66-8.76%). Spearman's r correlations showed significant relationships between CRO asymmetry and CODS90 performance on both limbs (r = 0.48-0.51; p < 0.05) and CODS180 (r = 0.41-0.51; p < 0.05) and a sprint test (r = 0.46; p < 0.05). These results show the test-specific nature of asymmetries in youth handball players, with iso-inertial device and CODS deficit presenting the greatest magnitude of asymmetries. Furthermore, interlimb differences during iso-inertial device (CRO) were associated with reduced CODS and sprint performance. These results suggest that the use of iso-inertial devices for the detection of interlimb asymmetry may be more effective than the total time during traditional CODS tests and that larger imbalances are associated with reduced athletic performance in youth handball players., (Copyright © 2019 National Strength and Conditioning Association.)

The COVID-19 pandemic has produced a major disruption for professional football leagues that has affected the physical preparation of both football players and referees. In Spain, health authorities decreed home confinement for eight weeks, supressing the normal training routines of professional referees. After home confinement, referees had four weeks to retrain as the national football league was set to resume matches to complete the 11 games remaining. The aim of the present investigation was to assess changes in eccentric hamstring muscle strength during football competition suspension/resumption due to the COVID-19 pandemic in 21 professional football referees (mean ± SD, age: 33.4 ± 5.1 years; height: 182.4 ± 5.0 cm; body mass: 75.1 ± 4.4 kg). Eccentric hamstring muscle strength was measured with the Nordic hamstring exercise at four time points. During home confinement, referees presented the lowest value of bilateral eccentric muscle strength (300 ± 14 N). Eccentric muscle strength increased by 13.2 ± 3.7% one week after the end of home confinement (339 ± 16 N; p = 0.001, effect size (ES) = 2.8) and remained stable before the first match (343 ± 17 N; p = 0.001, ES = 3.1) and after the end of the national league (328 ± 13 N; p = 0.001, ES = 2.0). In summary, home confinement produced detraining effects in professional football referees associated with hamstring muscle weakness. In this regard, strength-based activities with body loads may be insufficient to avoid muscle weakness and other means (e.g., weights) may be necessary to maintain muscle strength. However, the 4-weeks retraining period was sufficient to resolve hamstring muscle weakness induced by the restrictions of home confinement. This information may be helpful in the case of future sport competition suspension or home quarantine due to new waves of COVID-19 pandemic.

In this study, we aimed to analyze the magnitude and direction of inter-limb asymmetries in ankle dorsiflexion range of motion (ROM), power (using iso-inertial devices), and a neuromuscular skill (change of direction). Secondarily, we aimed to determine the relationship between inter-limb asymmetry scores for each test and also between these scores and the scores for the different performance tests. Sixteen semiprofessional male soccer players (age: 25.38 ± 6.08 years; body height: 1.78 ± 0.64 m; body mass: 79.5 ± 14.9 kg) participated in this study. We calculated inter-limb asymmetries using five tests: ankle dorsiflexion ROM, change of direction (COD 180º), and iso-inertial resistance tasks in the open (leg extension strength (LE), leg curl strength (LC)) and closed (crossover step (CRO)) kinetic chain. Our results showed that asymmetry magnitudes differed between all tests with highest inter-limb asymmetries displayed during iso-inertial overloading. In addition, we observed that the direction of asymmetries varied depending on the test-specificity, and that the CRO asymmetries had a negative association with LE and CRO performance. These findings highlight the independent nature of asymmetries and that CRO could be an appropriate test to detect asymmetries related with the performance of soccer-specific actions (such as changes of direction). Practitioners are encouraged to use multiple tests to detect existing inter-limb differences according to the specific characteristics of each sport., (© 2021 Marc Madruga-Parera, Thomas Dos’Santos, Chris Bishop, Anthony Turner, David Blanco, Vicente Beltran-Garrido, Victor Moreno-Pérez, Daniel Romero-Rodríguez.)

Practitioners usually include change of direction (COD) and linear speed measurements in the testing batteries of soccer players; however, despite being a commonly occurring action, curve sprint (CS) ability is rarely assessed in soccer. The aims of this study were to analyze the association between linear sprint, CS, and COD speed performances, and compare the association and direction of asymmetries between these skills. Thirty-three male soccer players performed linear sprint (17 m), CS (17 m), and COD-90 ⍛ speed tests (COD [8.5 + 8.5 m]). Our main findings were (a) a large relationship between linear and multidirectional tasks (COD-90 ⍛ and CS tests) (r = from 0.6 to 0.64, p < 0.05), (b) a moderate relationship between CS and COD-90 ⍛ tests (r = from 0.33 to 0.41, p < 0.05), with a certain opposite tendency (higher relationships between opposing directions [Curve LEFT - COD RIGHT ; r = 0.41] than between equal directions [Curve LEFT - COD LEFT ; r = 0.33]), and (c) no relationship (p > 0.05) between COD and CS asymmetries, with opposing directional dominance in ~70% of players (e.g., curve left and COD right dominance). These results indicate that performance in linear sprints is strongly related to performance in multidirectional trajectories, whereas CS and COD-90 ⍛ seem to be more independent actions. Additionally, the direction of asymmetry or dominance is generally opposite between the non-linear tasks measured., (© 2021 Alberto Fílter, Vicente Beltrán-Garrido, Thomas Dos’Santos, Daniel Romero-Rodríguez, Bernardo Requena, Irineu Loturco, Marc Madruga-Parera, published by Sciendo.)

Madruga-Parera, M, Bishop, C, Fort-Vanmeerhaeghe, A, Beltran-Valls, MR, Gonzalo-Skok, O, and Romero-Rodríguez, D. Interlimb asymmetries in youth tennis players: relationships with performance. J Strength Cond Res 34(10): 2815-2823, 2020-Change of direction speed (CODS) has been highlighted as a critical component of tennis. Interlimb asymmetries have been commonly studied in jump tests, but less attention given to the topic during CODS. The aim of this study was to quantify interlimb asymmetries in jumping and CODS (during traditional and isoinertial tests) and establish their relationship with measures of physical performance. Twenty-two elite youth tennis players (16.3 ± 1.4 years) performed single-leg countermovement jump (SLCMJ), single-leg broad jump, and single-leg lateral jump, a double 180° turn CODS test, and shuffle lateral step and crossover step with an isoinertial resistance device. Paired-samples t-tests revealed significant differences between limbs for all tests (p < 0.05). Interlimb asymmetry scores ranged from 1.83 to 15.03%, and a 1-way repeated-measures analysis of variance showed significant differences between interlimb asymmetry scores across multiple tests (p < 0.05). Spearman's rank order r correlations showed significant negative relationships between CODS asymmetry and SLCMJ performance on both limbs (r = -0.50; p = 0.02 and r = -0.53; p = 0.01) and CODS performance on both limbs (r = 0.50; p = 0.02 and r = 0.63; p = 0.002). These results show the test-specific nature of asymmetries in youth tennis athletes, with the SLCMJ presenting the greatest magnitude of asymmetry. Furthermore, interlimb differences during CODS were associated with reduced performance during jumping and CODS tests, suggesting the monitoring of asymmetries within this population may therefore be warranted.

This study aimed to analyze the influence of the inertial load on both concentric and eccentric power output production during the flywheel leg curl exercise, and to assess the reliability of power output variables. Sixteen participants (8 males, 8 females) attended 4 testing sessions. During testing, participants performed one set of eight repetitions using a specific inertial load (0.083, 0.132, 0.182, 0.266 and 0.350 kg·m 2 ) with a flywheel leg curl exercise. Concentric (CON) power, eccentric (ECC) power and the ECC/CON ratio were analyzed. The reliability analysis between sessions was performed. A significant interaction of inertia load x gender was found in CON power (p < 0.001) and in ECC power (p = 0.004), but not in the ECC/CON ratio (p = 0.731). A significant with-in (inertia loads) effect was found in CON power (p < 0.001) and in ECC power (p < 0.001), but not in the ECC/CON ratio (p = 0.096). CON power showed very high reliability scores, ECC power showed high to very high reliability scores, while the ECC/CON ratio ranged from poor to moderate. A significant between gender effect was found in CON power (p < 0.001) and in ECC power (p < 0.001), but not in the ECC/CON ratio (p = 0.752). This study is the first to report that power output in the flywheel leg curl exercise is altered by the inertia load used, as well as power output is different according to gender. CON and ECC power output presents high to very high reliability scores, and the ECC/CON ratio should not be used instead. These results can have important practical implications for testing and training prescription in sports., (© 2020 Francisco Piqueras-Sanchiz, Rafael Sabido, Javier Raya-González, Marc Madruga-Parera, Daniel Romero-Rodríguez, Marco Beato, Moisés de Hoyo, Fabio Yuzo Nakamura, Jose Luis Hernández-Davó, published by Sciendo.)

The aim of this study was to investigate the acute (a football match) and chronic (a whole season) effects of competition on ankle dorsiflexion ROM in professional football players. Forty football players participated in this study. Ankle dorsiflexion ROM was recorded to examine acute (pre-match, immediately post-match and 48 h post-match) and chronic (pre-season, mid-season and post-season) effects of competitive football. In addition, it was found that players had restricted mobility measures on ankle dorsiflexion as >2 cm change between baseline measures (pre-match and pre-season). The training load of all played matches was estimated using a global positioning system (GPS) and RPE. Pre-season ankle dorsiflexion ROM was greater compared to mid-season (8.1% in the dominant, and 9.6% in the non-dominant leg) and post-season (13.8% in the dominant, and 12.5% in the non-dominant leg). In addition, around 30% of all players showed restricted ankle dorsiflexion ROM values in post-season compared with pre-season. Related to acute effects, ankle dorsiflexion ROM increased after a match (5.8%) in the dominant ankle, and this value decreased (2.65%) 48 h post-match when post-match measurements in both dominant and non-dominant ankles were compared. The progressive decrease in ankle dorsiflexion ROM throughout a season can be an indicator of increased risk of injury and may be reinforce the need of prevention actions such as stretching exercises and eccentric strength training in professional football players. In addition, these findings suggest to implement specific recovery strategies aiming at minimizing alteration in ankle dorsiflexion ROM 48 h post-match.

The aim of the present investigation was to analyze the validity and reliability of a novel iPhone app (CODTimer) for the measurement of total time and interlimb asymmetry in the 5 + 5 change of direction test (COD). To do so, twenty physically active adolescent athletes (age = 13.85 ± 1.34 years) performed six repetitions in the COD test while being measured with a pair of timing gates and CODTimer. A total of 120 COD times measured both with the timing gates and the app were then compared for validity and reliability purposes. There was an almost perfect correlation between the timing gates and the CODTimer app for the measurement of total time (r = 0.964; 95% Confidence interval (CI) = 0.95-1.00; Standard error of the estimate = 0.03 s.; p < 0.001). Moreover, non-significant, trivial differences were observed between devices for the measurement of total time and interlimb asymmetry (Effect size < 0.2, p > 0.05). Similar levels of reliability were observed between the timing gates and the app for the measurement of the 6 different trials of each participant (Timing gates: Intraclass correlation coefficient (ICC) = 0.651-0.747, Coefficient of variation (CV) = 2.6-3.5%; CODTimer: ICC = 0.671-0.840, CV = 2.2-3.2%). The results of the present study show that change of direction performance can be measured in a valid, reliable way using a novel iPhone app.

Neuromuscular asymmetries have been previously associated with reduced performance. Similarly, maturation has shown that youth athletes may experience a loss of motor control, which could also lead to compromised physical performance. The present study aimed to evaluate and quantify the level of asymmetry among chronological and maturational groups. Forty-one youth tennis players performed the single leg countermovement jump (SLCMJ), star excursion balance test (SEBT) and a change of direction speed (CODS) test. Differences were found between the strongest and weakest limbs across all tests ( p < 0.001), and also for SEBT in the posteromedial direction ( p = 0.02), SEBT composite score ( p < 0.01) in maturation groups, and for SEBT posterolateral direction ( p = 0.03) and SEBT composite score ( p = 0.01) in chronological groups. The SLCMJ showed the largest inter-limb asymmetries for the circa peak height velocity (PHV) group (19.31 ± 12.19%) and under-14 (U14) group (17.55 ± 9.90%). Chronological and maturation groups followed similar trends for inter-limb asymmetries, but the biological index showed larger asymmetry scores in the jumping test at PHV compared to that found in the chronological group (U14). These results show that inter-limb differences may be heightened during PHV. Practitioners can use this information to inform the decision-making process when prescribing training interventions in youth tennis players.

CD8+ T cell-mediated immune response plays a major role in the clearance of virus-infected cells, including human papillomavirus (HPV). The effective treatment of women with normal cytology but persistent high risk-HPV infection or with low-grade intraepithelial lesions could take advantage of novel strategies based on vaccination with viral immunological targets with a wide spectrum of cross-protection. The helicase E1, expressed early during viral replication in HPV infection, is among the most conserved papillomavirus proteins, which makes it a good vaccine candidate. In the present study, we examined E1-specific CD8+ T cell and NK immune responses in a mouse model with α-galactosylceramide (α-GalCer) as an adjuvant. We found that mice immunized with E1 combined with α-GalCer elicited an E1-specific CD8+ T and NK cell cytotoxic responses, which correlated with growth inhibition of grafted melanoma B16-F0 cells expressing E1, both in prophylactic and therapeutic protocols., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Gual, G, Fort-Vanmeerhaeghe, A, Romero-Rodríguez, D, and Tesch, PA. Effects of in-season inertial resistance training with eccentric overload in a sports population at risk for patellar tendinopathy. J Strength Cond Res 30(7): 1834-1842, 2016-Volleyball and basketball players can be considered as a population at risk for patellar tendinopathy. Given the paradox that eccentric training elicits therapeutic benefits yet might provoke such injury, we investigated the influence of a weekly bout of inertial squat resistance exercise offering eccentric overload on lower limb muscle power and patellar tendon complaints. Players of 8 (4 basketball and 4 volleyball) teams (38 women and 43 men) were randomly assigned to either the intervention (IG) or control (CG) group. Although IG and CG maintained scheduled in-season training routines over 24 weeks, IG, in addition, performed 1 weekly session of eccentric overload by 4 sets of 8 repetitions of the squat using flywheel inertial resistance. Victorian Institute of Sports Assessment patellar tendinopathy questionnaire (VISA-p), vertical countermovement jump, and squat power, both concentric (Squat-Con) and eccentric (Squat-Ecc), tests were performed before (T1), during (T2), and after (T3) the 24 weeks of intervention. Neither group suffered from patellar tendinopathy during the study period. VISA-p displayed no differences across groups at any measurement period. Countermovement jump scores significantly (p ≤ 0.05) differed between groups in favor of the IG. Both Squat-Con and Squat-Ecc mean scores from the IG were significantly (p < 0.01) higher than the CG. Adding a weekly eccentric overload squat training bout to a regular basketball and volleyball exercise routine enhances lower limb muscle power without triggering patellar tendon complaints. Future studies, using the current exercise paradigm, aim to explore its efficacy to prevent or combat patellar tendinopathy in sports calling for frequent explosive jumps.

Objectives: To assess the efficacy of an exercise program on a whole-body vibration platform (WBV) in improving body balance and muscle performance and preventing falls in institutionalized elderly people., Design/setting/participants: A multicentre randomized parallel assessor-blinded clinical trial was conducted in elderly persons living in nursing homes., Interventions: Participants were randomized to an exercise program performed either on a whole body vibratory platform (WBV plus exercise group) or on a stationary surface (exercise group). The exercise program for both groups consisted of static and dynamic exercises (balance and strength training over a 6-week training period of 3 sessions per week). The frequency applied on the vibratory platform was 30 to 35 Hz and amplitude was 2 to 4 mm., Measurements: The primary outcome measurement was static/dynamic body balance. Secondary outcomes were muscle strength and number of falls. Efficacy was analyzed on an intention-to-treat basis and per protocol. The effects of the intervention were evaluated using the t test, Mann-Whitney test, or chi-square test, depending on the type of outcome. Follow-up measurements were collected 6 weeks and 6 months after randomization., Results: A total of 159 participants from 10 centers were included: 81 in the WBV plus exercise group and 78 in the control group. Mean age was 82 years, and 67.29% were women. The Tinetti test score showed a significant overall improvement in both groups (P < .001). No significant differences were found between groups at week 6 (P = .890) or month 6 (P = .718). The Timed Up and Go test did not improve (P = .599) in either group over time, and no significant differences were found between groups at week 6 (P = .757) or month 6 (P = .959). Muscle performance results from the 5 Sit-To-Stand tests improved significantly across time (P = .001), but no statistically significant differences were found between groups at week 6 (P = .709) or month 6 (P = .841). A total of 57 falls (35.8%) were recorded during the follow-up period, with no differences between groups (P = .406)., Conclusion: Exercise program on a vibratory platform provides benefits similar to those with exercise program on a stationary surface in relation to body balance, gait, functional mobility, and muscle strength in institutionalized elderly people. Longer studies in larger samples are needed to assess falls., (Copyright © 2015 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Whole-body vibration (WBV) may be a complementary training to standard physical rehabilitation programmes and appears to have potential benefits in the sensorimotor system performance of patients with neurodegenerative diseases., Objectives: The aim of this review was to examine the efficacy of WBV to improve functional performance according to basic activities of daily living (ADL) in neurodegenerative diseases. Additionally, we wanted to assess the possible effect on signs and symptoms of the disease, body balance, gait, muscle performance, quality of life and adverse events., Search Methods: We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2011 Issue 4), MEDLINE (1964 to 6 May 2011; via PubMed), EMBASE (1980 to 6 May 2011; via Ovid), PeDro (1929 to May 2011; via website), CINAHL (to September 2011; via Ovid) and PsycINFO (1806 to 6 May 2011; via Ovid)., Selection Criteria: We included randomised controlled trials comparing single or multiple sessions of WBV to a passive intervention, any other active physical therapy or WBV with different vibration parameters., Data Collection and Analysis: Two review authors independently selected trials for inclusion, assessed trial quality and extracted data. Disagreement was resolved by discussion or, if necessary, referred to a third review author., Main Results: We included 10 trials, of which six focused on Parkinson's disease and four on multiple sclerosis. None of the studies reported data on the primary outcome (functional performance). In Parkinson's disease, after pooling two studies, a single session of WBV caused a significant improvement of gait measured using the Timed Up and Go test (TUG) in comparison to standing exercises (mean difference -3.09, 95% confidence interval -5.60 to -0.59; P = 0.02; I(2) = 0%). Nevertheless, longer duration of WBV did not show significant results in comparison with physical therapy in body balance or signs and symptoms measured with the Unified Parkinson's Disease Rating Scale (UPDRS). In multiple sclerosis there was no evidence of a short-term or long-term effect of WBV on body balance, gait, muscle performance or quality of life.Adverse events were reported in few trials. In those trials that reported them, the intervention appeared to be safe., Authors' Conclusions: There is insufficient evidence of the effect of WBV training on functional performance of neurodegenerative disease patients. Also, there is insufficient evidence regarding its beneficial effects on signs and symptoms of the disease, body balance, gait, muscle strength and quality of life compared to other active physical therapy or passive interventions in Parkinson's disease or multiple sclerosis. More studies assessing other functional tests and accurately assessing safety are needed before a definitive recommendation is established.

Purpose: The aim of this study was to perform a systematic review of the literature on whole body vibration programs in older population and a meta-analysis of randomized controlled clinical trials., Method: A search was conducted in MEDLINE, EMBASE, CENTRAL, CINAHL and PsychINFO databases. We included randomized controlled trials evaluating the efficacy and safety of whole body vibration training in older populations compared to conventional exercise or control groups that assessed balance, muscle strength, falls, bone mineral density and adverse events., Results: Sixteen trials met the inclusion criteria. Comparing the vibration and the control group, we found that vibration significantly improved knee muscle isometric strength (18.30 Nm, 95% CI 7.95-28.65), muscle power (10.44 W, 95% CI 2.85-18.03) and balance control (Tinetti test: 4.5 points, 95% CI 0.95-8.11). Comparison with a conventional exercise showed that the only significant difference was bone mineral density in the femoral neck (0.04 g/cm(-2), 95% CI 0.02-0.07). There were no serious complications in most of studies., Conclusion: Whole body vibration training may improve strength, power and balance in comparison with a control group, although these effects are not apparent when compared with a group that does conventional exercise.

Objective: To describe the clinical course of infection by 2009 (H1N1) influenza virus in different stages of HIV disease., Design: Prospective, observational study., Methods: During the pandemic period, HIV-infected patients presenting respiratory symptoms at a third level referral hospital in Mexico City were tested for 2009 influenza A (H1N1) viral RNA. Clinical files were prospectively analyzed., Results: Infection by H1N1 was confirmed in 30 (23.8%) of the total 126 HIV-infected patients studied. In the group of patients with 2009 H1N1 virus infection, 16 (53.3%) were hospitalized, 12 (40%) had active opportunistic infections and six (20%) died. In the group of 96 patients not infected with 2009 H1N1 virus, 54 (56.25%) were hospitalized with opportunistic infections and 12 (12.5%) died. For all hospitalized patients, being on HAART and having undetectable HIV viral loads at hospitalization was associated with higher survival (P = 0.019). Patients with 2009 H1N1 virus infection had a higher mortality rate, even after adjusting for HAART (P = 0.043). Coinfection by HIV and H1N1 2009 virus was more severe in patients with opportunistic infections, as shown by longer hospital stays (P = 0.0013), higher rates of hospitalization (P < 0.0001), use of mechanical ventilation (P = 0.0086) and death (P = 0.026). Delayed administration of oseltamivir in hospitalized patients was significantly associated with mortality (P = 0.0022)., Conclusion: Our data suggest that infection by 2009 H1N1 is more severe in HIV-infected patients with late and advanced HIV disease than in well controlled patients under HAART.