Background: Volleyball requires explosive jumps, agility, and upper and lower limb coordination. Dynamic stretching (DS) and core stability (CS) protocols are often used separately in training sessions, but little is known about their combined effects on the performance in adolescent players. This study aimed to investigate the impact of a 12-week integrated DS and CS program (StretCor), in addition to standard training, on physical performance in U-16 volleyball players. Methods: Twenty-one volunteer players (15.1 ± 0.6 years) were randomly assigned to the Intervention Group (IG; n = 12) or Control Group (CG; n = 9). IG performed the StretCor protocol four times a week for twelve weeks in addition to standard volleyball training; CG continued standard volleyball training. Physical performance assessment included Countermovement Jump (CMJ), Vertec jump with run-up, isometric shoulder strength (ASH-I), dynamic balance (mSEBT), and agility (t-test) tests. Results: Significant group × time interactions (p < 0.05, η² ranged: 0.20–0.90) were found for CMJ height and peak power, Vertec jump, ASH-I, mSEBT scores, and t-test performance. Post hoc analyses showed improvements in IG for CMJ height (+16.5%), Vertec jump (+10.2%), shoulder strength (+11–14%), balance across directions (+8–12%), and agility (−5.7% t-test time). No significant changes were observed in CG. Conclusions: The present study suggests that a 12 weeks of StretCor protocol training improves jump performance, agility, dynamic balance, and upper limb strength in U-16 volleyball players. These findings also support that StretCor protocol may be beneficial for the performance when incorporated into regular training programs for adolescent athletes.

Background: Physical inactivity and prolonged sedentary behavior have been associated with impaired cognitive function during adolescence. Although classroom-based active breaks (ABs) have shown promising effects in primary school children, evidence among adolescents attending upper secondary schools remains limited. This study evaluated the effects of a four-month classroom-based ABs program on attention and concentration performance and explored whether selected participant and lifestyle-related characteristics moderated the intervention response. Methods: In this cluster-randomized controlled trial, 529 adolescents (302 females, 227 males; 14.3 ± 0.9 years) from 39 classes attending four upper secondary schools in Southern Italy were included. Classes were randomly allocated to the intervention group (IG; 20 classes, n = 288) or control group (CG; 19 classes, n = 241). The IG participated in two daily 10 min classroom-based ABs for four months, whereas the CG followed the usual school routine. At baseline, anthropometric characteristics, sport participation, sleep duration, daily smartphone use, adherence to the Mediterranean Diet, and concentration performance (CP score), assessed by the d2-R Test of Attention, were evaluated; only CP was reassessed after the intervention. Results: The primary mixed-effects model showed significantly higher adjusted post-intervention CP in the IG than in the CG (adjusted between-group difference = 56.7 points, 95% CI 21.7–91.6; p = 0.003). The intervention effect remained significant in a fully adjusted model including sex, organized sport participation, sleep duration, smartphone use, and Mediterranean Diet adherence (p = 0.004). Exploratory moderator analyses provided no evidence that the intervention effect differed according to any of these characteristics after correction for multiple testing. Conclusions: A four-month classroom-based ABs program can improve concentration performance among adolescents. High intervention fidelity and student attendance support the feasibility of implementing structured ABs within the school setting over the intervention period. Further research is needed to determine the long-term effects and implementation of ABs program in secondary schools.

During aging, modifiable lifestyle factors, such as physical activity, play an increasingly important role. Specifically, it is known that physical fitness declines relatively predictably with age and that resistance training can be a highly effective strategy for preventing this decline, both at muscular and cognitive levels. Several studies have described that one of the mechanisms mediating some of the beneficial effects of physical exercise during aging is the regulation of miRNAs, and in particular, the miR-29 family appears to play a relevant role. In this review, we analyse, firstly, the relevance of the miR-29 family in aging and, secondly, the protective effects of resistance exercise in delaying age-related dysfunction through the regulation of miR-29.