Biology of Sport最新文献

This study aimed to investigate whether two DCN gene single nucleotide polymorphisms (SNPs), rs13312816 (T > A) and rs516115 (A > G), are associated with the risk and severity of anterior cruciate ligament (ACL) injury. A total of 296 physically active, unrelated Caucasian males participated: 160 with noncontact ACL injuries and 136 healthy controls. Genotyping was conducted using TaqMan assays. Logistic regression and haplotype-based analyses were performed, adjusting for age and body mass. The minor A allele of rs13312816 was significantly more frequent in ACL cases than in controls (8.54% vs. 2.94%, P = 0.0047; OR = 3.08, 95% CI: 1.33-7.98). Individuals with the A/T genotype had higher odds of injury compared to T/T carriers (P_adj = 0.008; OR = 3.3, 95% CI: 1.44-7.53). No associations were found for rs516115 in the case- control comparison. Haplotype analysis showed that individuals with the [A;G] haplotype had increased odds of ACL injury (P_adj = 0.0095; OR = 3.29, 95% CI: 1.44-7.52). Within the injured group, rs13312816 A/T genotype was associated with multiple injuries (ACLF) (P_adj = 0.010; OR = 3.19, 95% CI: 1.36-7.48). For rs516115, both A/G (P_adjj < 0.0001; OR = 6.03, 95% CI: 2.83-12.83) and G/G genotypes (P_adj < 0.0001; OR = 9.71, 95% CI: 2.57-36.77) were linked to ACLF. Haplotype analysis confirmed increased odds for multiple injuries in carriers of [A;G] (P_adj = 0.0099; OR = 3.34, 95% CI: 1.33-8.35) and [T;G] haplotypes (P_adj < 0.0001; OR = 4.79, 95% CI: 2.35-9.79). These findings suggest that DCN genetic variants, especially rs13312816 and specific haplotypes, contribute to ACL injury susceptibility and recurrence.

Integrin complexes facilitate cell communication, playing a role in ligament homeostasis. ITGB2 rs2230528 (C/T) was implicated in anterior cruciate ligament rupture (ACL) risk in a South African cohort. Identifying biologically significant DNA signatures in the predisposition to ACL rupture risk remains important towards understanding mechanisms of ACL ruptures. ITGB2 is essential for the activation of important biological pathways regulated by structural components such as collagens and biomechanical components such as vasculo-endothelial growth factors. This study tested the association of (i) ITGB2 rs2230528 and (ii) allele-allele combinations of ITGB2's network partners (COL5A1 rs12722 C/T, VEGFA rs699947 C/A and VEGFA rs2010963 G/C) with ACL rupture risk. The genetic study was conducted in a combined cohort [n=1279: uninjured controls (CON), n=548; ACL ruptures (ACL), n=731; subgroup with non-contact mechanism of ACL ruptures (NON, n=425)] recruited from Australia, Poland, Sweden and South Africa. The combined cohort, rs2230528 TT (best fit model) was significantly over-represented in the ACL (p=8.00 × 10^-8; OR:3.21; 95% CI:2.10-4.89, AIC=1549) and NON (p=1.59 × 10^-6; OR:3.11; 95% CI:1.97-4.91, AIC=1191) groups compared to CON. ITGB2 rs2230528-COL5A1 rs12722-VEGFA rs699947-VEGFA rs2010963, the C-C-A-G and C-T-C-G combinations were significantly associated with reduced ACL risk. This study provided additional evidence highlighting ITGB2 as potentially being associated with ACL ruptures even though the gene-gene combinations had a small effect size. Integrins containing the b2 subunit together with its key extracellular matrix components (type V collagen and VEGFA) are potential therapeutic targets for ACL ruptures and potentially other connective tissue-related conditions.

The aim of the study was to examine the effects of eccentric- and concentric-based plyometric programmes on the strength, speed, and tensiomyography (TMG) parameters of female athletes. The study included twenty junior female participants from three different sports equally divided into two experimental groups of n = 10. Two plyometric programmes with contrasting designs were conducted for a period of six weeks, with sessions held twice per week. The first plyometric programme (ECC-CON-G) was based on exercises with eccentric, and the second (CONC-CON-G) with concentric contractions. TMG was used to evaluate neuromuscular performances of six muscles of both legs - vastus lateralis (VL), vastus medialis (VM), biceps femoris (BF), semitendinosus (SM), gastrocnemius lateralis (GL), and gastrocnemius medialis (GM)) - and two strength and speed tests: countermovement jump (CMJ), and sprint test at 10 m and 20 m. The results show that both groups had significant effects between pre-post measurements in CMJ (Diff, ECC-CON-G = 9.02%, and CONC-CON-G = 5.59%, p < 0.05), at 10 m (Diff, ECC-CON-G = 9.23%, and CONC-CON-G = 9.35%, p < 0.001), and 20 m (Diff, ECC-CON-G = 6.16%, and CONC-CON-G = 5.35%, p < 0.001), and TMG parameters in ECC-CON-G (all 6 left leg muscles, and right leg-VL, BF, GL, GM, p < 0.05), in CONC-CON-G (left leg-BF, SM, GL, GM, and right leg-VL, BF, GL, GM, p < 0.05). There were significantly better effects in ECC-CON-G compared to CONC-CON-G for CMJ height and time, for only time in 20 m sprint, and TMG parameters for left leg VL and VM, and right leg BF and GM. A plyometric programme based on exercises with eccentric contractions proved more beneficial for strength, speed, and TMG parameters in young female athletes compared to a programme based on concentric contractions.

Due to the dynamic and complex nature of soccer, match-running performance (MRP) is highly influenced by match content. This study aimed to examine the interaction between possession status (PS) and possession percentage (PP) in relation to match-running performance (MRP) and to quantify MRP in each PS while considering multiple contextual variables. MRP indicators, including total distance (TD) and high-intensity running distance (HID), were collected from 8,468 observations of 412 outfield male players in the 2018-2019 Spanish LaLiga, excluding matches with red cards. This study set PS, possession percentage (PP), effective playing time, match location, quality of opposition, and match results as fixed effects, and set players and teams as random effects. Results indicated: i) PP interacted with PS, negatively affecting TD (r = -0.26, p < 0.05) and HID (r = -0.11, p < 0.05) during IP but positively influencing TD (r = 0.24, p < 0.05) and HID (r = 0.28, p < 0.05) during OP; ii) MRP during in-possession exceeded out-of-possession when PP was below 36% for TD and 36.4% for HID; iii) PP thresholds for MRP shifts varied by position, with forwards requiring higher PP (TD: 61.8%, HID: 68.6%) compared to central defenders (TD: 28.3%, HID: 9.2%). This study reveals the interaction effects of PS and PP on MRP, emphasizing the complexity of multivariate relationships in soccer. It underscores the importance of multivariate approaches over traditional methods like t-tests, which provide only partial insights.

Enhancing physical activity and managing body weight are crucial for addressing aging-related challenges. However, research on the relationship between physical activity, Weight-Adjusted Waist Index (WWI), and all-cause mortality is limited. This study aims to explore these interactions and their impact on elderly health. Data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) for 2011-2018 included 7,034 residents aged ≥ 60 years. We utilized Cox proportional hazard models to assess the relationships between physical activity, WWI, and all-cause mortality, supplemented by subgroup analyses and interaction tests. We did a mediation analysis to assess how much of the effect of physical activity on survival status was mediated through WWI. Active individuals and those transitioning from inactive to active lifestyles exhibited significantly lower all-cause mortality risks, with reductions of 26% (HR = 0.74, CI: 0.65-0.83) and 9% (HR = 0.91, CI: 0.83-0.99), respectively. A positive correlation was found between WWI and all-cause mortality, with a threshold of 11.38 cm/√kg indicating increased risk. Although no interaction between physical activity and WWI was observed (P = 0.462), mediation analysis showed that 3.06% of the effect of physical activity on survival status was mediated through WWI. Maintaining physical activity or transitioning from a sedentary lifestyle to an active one can significantly reduce all-cause mortality in the elderly. Moreover, high WWI is associated with an increased risk of death. Importantly, WWI partially mediates the relationship between physical activity and death, shedding light on why physical activity reduces mortality and reinforcing the need for health promotion strategies tailored to the elderly population.

Intermittent sequential pneumatic compression (ISPC) is used to improve readiness and recovery in athletes. This study aimed to evaluate the effects of daily use of ISPC for 5 weeks on the performance, physiological, and psychological parameters in seventeen male handball players. Players were randomly assigned either to an experimental (EXP, n = 8) or a control (CON, n = 9) group. Before and after the intervention, we measured the countermovement jump (CMJ) and the agility test (T-test) as markers of sport-specific performance, the systolic blood pressure (SBP) in the brachial and ankle arteries to evaluate the hemodynamic function, and the tensiomyography of biceps femoral, gastrocnemius and vastus medialis to assess muscle function. During the intervention, the session rating of perceived effort (sRPE, 30 minutes after training) and perceived recovery status (PRS, 1 hour after waking-up the following morning) were registered to evaluate subjective recovery. Results showed that CON experienced a decrease in agility performance from pre- to post-intervention (p = 0.030). In contrast, EXP had a significant improvement in the muscle contraction delay time of the left biceps femoris (p = 0.002), and a significant decrease in ankle SBP after the intervention (p = 0.017). Regarding perceived fatigue and recovery, EXP had slightly higher values than CON in PRS (p = 0.047), while sRPE had no significant changes. Thus, daily use of intermittent pneumatic compression for 5 weeks during a training period slightly mitigates the fatigue-induced effects of training, while enhancing hemodynamic regulation and subjective recovery in competitive handball players.

Soccer players who are non-starters typically experience reduced match loads, which can hinder their physical fitness and match readiness over time. This study aimed to investigate the running demands accumulated during top-up sessions in comparison to soccer matches. Twenty-six outfield soccer players from an elite Portuguese soccer team participated in this study. The following running variables were recorded: total distance (TD), running (14.4 to 19.7 km · h^-1), high-speed running (HSR: 19.8 to 25.1 km · h^-1), sprinting (≥ 25.2 km · h^-1) distances, number of sprints (counts), number of accelerations (ACC; 2-3 m · s^-2 and > 3 m · s^-2), decelerations (DEC; 2-3 m · s^-2 and > 3 m · s^-2), and player load. A linear mixed-effects model was used to examine differences between top-up sessions and matches. Overall, non-starters accumulated lower running load during top-up sessions than matches for most of the variables analyzed, but in particular TD (p < 0.001; ES range 2.46 to 3.74), running (p < 0.001; ES range 2.93 to 3.90), HSR (p < 0.001; ES range 2.21 to 3.47), sprints events (p < 0.001; ES range 1.16 to 2.76), ACC > 3 m · s^-2 (p < 0.005; ES range 0.98 to 1.37), DEC > 3 m · s^-2 (p < 0.001; ES range 1.91 to 2.66), and player load (p < 0.001; ES range 2.34 to 3.23). Therefore, non-starters accumulated less than half of the total match distance for most of the running metrics during top-up sessions. These findings suggest that compensatory training should be designed to more closely replicate match demands, with particular attention to high-intensity demands, such as HSR and sprints.

To determine how absence time after muscle injuries affects external load metrics in elite soccer players and identify which performance variables are most impacted by the injury. A total of 110 lower limb muscle injuries from LaLiga players were analysed. Following an analysis of pre- and post-injury data to identify which outcomes were affected by muscle injury, machine learning algorithms were employed to examine relationships between absence duration and performance metrics. Maximal speed, maximal acceleration, maximal deceleration, composite index (i.e., overall player performance) and sprint count during matches were the most affected variables after return to play. The multiple linear regression (MLR) model and random forest regression (RFR) presented an R² of 0.348 and 0.442. Maximal speed was the variable most strongly associated with absence time in both models (coefficient in MLR = 7.94; mean absolute SHAP value in RFR model = 4.99), with longer recovery periods correlating with reduced match performance in this metric. Maximal acceleration and deceleration also showed declines with increased absence time. In contrast, sprint count exhibited no significant relationship with absence time. Maximal speed, acceleration and deceleration capacity, as well as sprint count and overall performance, are affected after muscle injuries. However, prolonged recovery following muscle injuries especially reduces maximum speed and acceleration/deceleration capacity in elite players during matches, while sprinting actions remain unaffected by absence time.

This study aimed to characterise the locomotor characteristics of intense relative accelerations (> 50% of maximal acceleration-speed profile) according to playing positions in top-ranked Spanish football teams. A total of 271,535 accelerations performed by 102 football players of the top four teams during the 2023-2024 LaLiga season were registered by a multiple-camera computerised tracking system (TRACAB; ChyronHego, USA). A generalized linear mixed model compared the acceleration characteristics (number, distance, duration, intensity and speed) across playing positions (central defender: CD, full back: FB, central midfielder: CM, attacking midfielder: AM, winger: W and forward: FW) considering the effect of contextual variables. CD exhibited less intense accelerations per minute than the rest of the playing positions (p < 0.05). W exhibited the greatest distance per acceleration (estimated mean (EM) = 9.08 m), longest duration (EM = 2.18 s), highest peak speed (EM = 19.5 km · h^-1), and highest speed at maximum acceleration (EM = 12.8 km · h^-1) (p < 0.05). FW exhibited the highest peak acceleration per action (EM = 3.14 m · s^-2) and average acceleration per action (EM = 1.76 m · s^-2) (p < 0.05). AM and CM registered higher initial speed (p < 0.05) and exhibited the lowest values for peak acceleration per action (p < 0.05), compared to the other playing positions. In contrast, CD and CM showed the shortest distances and slowest speeds (p < 0.05). In conclusion, W and FW exhibited higher acceleration intensity than the rest of the playing positions, while CD and CM obtained the lowest values for distance, duration, and speed.

The aim of the present study was to examine the effect of a novel periodization model - integral periodization (IP) - that considers the load balance between game-specific demands and resistance training sessions and to compare it with the effect a traditional periodization model (TP) of resistance training (RT) on fitness through lower-body muscular strength, acceleration and speed, change of direction ability, and cardiorespiratory fitness performance, in addition to non-contact injury incidence in young, trained soccer players during a full season. Forty-five (n = 21 vs n = 24) trained soccer players (15.2 ± 0.1 years) were randomly divided into a TP training group (TPG) and an IP training group (IPG). High-intensity actions (HIAs) were evaluated through countermovement jump (CMJ), squat and hip-thrust progressive loading tests, a 10-m and 30-m sprint test, a V-cut test, and a 30-15 intermittent fitness test, and non-contact injuries were recorded. In RT sessions, TPG used exercises without variability that were repeated systematically, while IPG used variable exercises for compensating the load in reference to what was experienced on the pitch. The results showed significant improvements in all tests (ES: 0.42-4.43, all p < 0.05), except the 30-15 ITF (ES: 0.21-0.27, p = 0.114-0.332), in both groups. However, IPG showed significantly better results than TPG in 10-m (p < 0.001), 30-m sprint (p < 0.001), V-cut (p < 0.012), and non-contact injuries incidence (p < 0.028). In summary, IPG showed greater HIA improvements compared to TP and reduced non-contact injury incidence in young, trained soccer players.