Relationship among acceleration, change of direction ability and horizontal jump performance in young athletes.

The aim of this study was to analyze the relationship among the straight acceleration capacity, the change of direction ability (CODA) and the horizontal jumping (HJ) performance in young athletes. This study involved a total of 264 young athletes aged between 8 and 16 years (10.2 ± 2.6 years; 37.5 ± 11.7 kg, 1.4 ± 0.1 m, 17.7 ± 2.4 kg·m-2). The 5 and 15 m straight acceleration capacity, the CODA in the 505 test (505) and modified agility test (MAT), the horizontal counter movement jump (HCMJ) and the horizontal arm swing counter movement jump (HCMJAS) were assessed. The relationship between acceleration capacity in 5 m and CODA (505: r = 0.54, p 0.05) were more consistent than the association among 15 m test and CODA or HJ. The association between MAT test and HJ (HCMJ: r = -0.73, p <0.01; HCMJAS: r = -0.74, p <0.01) was higher than the relationship between 505 test and HCMJ (r = -0.63, p <0.01) or 505 test and HCMJAS (r = -0.61, p <0.01). The type, the duration and the nature of these field tests determine the associations among different motor skills. KEY WORDS: athletic, training, motor skills, agility, strengthEl objetivo de este estudio fue analizar la asociación existente entre la capacidad de aceleración en línea recta, la capacidad de cambiar de dirección (CODA) y la capacidad de salto horizontal (SH) en jóvenes atletas. En este estudio participaron un total de 264 jóvenes atletas de entre 8 y 16 años (10,2 ± 2,6 años; 37,5 ± 11,7 kg; 1,4 ± 0,1 m, 17,7 ± 2,4 kg·m-2). Se evaluó la capacidad de aceleración en línea recta en los test de 5 y 15 m, la CODA en el test 505 (505) y en el modified agility test (MAT) y la capacidad de SH con contra movimiento (HCMJ) y manos libres (HCMJAS). La asociación entre la capacidad de aceleración en 5 m y los test de CODA (505: r = 0,54, p 0,05) fue más consistente que la asociación entre la aceleración en 15 m y los test de CODA o SH. La asociación entre el test MAT y el SH (HCMJ: r = -0,73, p < 0,01 y HCMJAS: r = -0,74, p < 0,01) fue mayor que la relación observada entre el 505 y el HCMJ (r = -0,63, p < 0,01) o el HCMJAS (r = -0,61, p < 0,01). El tipo, la duración y la naturaleza de los test de campo utilizados, condicionan las asociaciones observadas entre las distintas habilidades motoras

Effectiveness of pertussis vaccination in pregnancy to prevent hospitalisation in infants aged <2 months and effectiveness of both primary vaccination and mother's vaccination in pregnancy in infants aged 2-11 months

Background: PERTINENT is an active hospital-based surveillance system for pertussis in infants. In 2019, four of the six participating European countries recommended pertussis vaccination in pregnancy. Among infants aged &lt;2 months, we measured the vaccine effectiveness (VE) in pregnancy; among infants aged 2-11 months, VE of vaccination in pregnancy and of primary vaccination (PV).Methods: From December 2015 to 2019, we included all infants aged &lt;1 year presenting with pertussis-like symptoms. Using a test-negative-design, cases were infants testing positive for Bordetella pertussis by PCR or culture. Controls were those testing negative for all Bordetella species. Vaccinated mothers were those who received vaccine in pregnancy. Vaccinated infants were those who received &gt;= 1 dose of PV &gt; 14 days before symptom onset. We excluded infants with unknown maternal or PV status or with mothers vaccinated &lt;= 14 days before delivery. We calculated pooled VE as 100 * (1-odds ratio of vaccina-tion) adjusted for study site, onset date in quarters and infants' age group.Results: Of 829 infants presenting with pertussis-like symptoms, 336 (41%) were too young for PV. For the VE in pregnancy analysis, we included 75 cases and 201 controls. Vaccination in pregnancy was recorded for 9 cases (12%) and 92 controls (46%), adjusted VE was between 75% [95%CI: 35-91%] and 88% [95%CI: 57-96%]. Of 493 infants eligible for PV, we included 123 cases and 253 controls. Thirty-one cases and 98 controls recorded both PV with &gt;= 1 dose and vaccination in pregnancy, adjusted VE was between 74% [95%CI: 33-90] and 95% [95%CI: 69-99]; 27 cases and 53 controls recorded PV only, adjusted VE was between 68% [95%CI: 27-86] and 94% [95%CI: 59-99]. Conclusion: Our findings suggest that vaccination in pregnancy reduces pertussis incidence in infants too young for PV. In infants aged 2-11 months, PV only and both PV and vaccination in pregnancy provide significant protection against severe pertussis.(c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)