Acute effects of static stretching and proprioceptive neuromuscular facilitation on non-local range of movement.

Acute effects of static stretching (SS) and proprioceptive neuromuscular facilitation (PNF) on local and non-local range of motion (ROM) were assessed in 29 participants. Three evaluations were performed one week apart: week-1 Control session (CS); weeks 2-3 either SS or PNF interventions (randomized). Dominant and non-dominant limbs, local (hamstring extensibility) and non-local ROMs (Shoulder extension-ShE) were collected at baseline (T0), immediately after (T1), and fifteen minutes post-intervention (T2). No differences were found between time-points during the CS. Local-ROM significantly increased (p=0.0002, ES=0.74 and 0.0079, 0.56, for dominant and non-dominant lower limbs, respectively) after both SS and PNF. No interaction between time and treatment was detected for ShE in both limbs. However, post-hoc analysis revealed a significant increase in dominant upper limb ShE between T0 and T1 only after SS (p=0.002; +6.5%). Acute bouts of SS and PNF can increase local-ROM, however, no clear effects were observed for non-local ROM.

Does Stretching Training Influence Muscular Strength? A Systematic Review With Meta-Analysis and Meta-Regression.

ABSTRACT: Thomas, E, Ficarra, S, Nunes, JP, Paoli, A, Bellafiore, M, Palma, A, and Bianco, A. Does stretching training influence muscular strength? A systematic review with meta-analysis and meta-regression. J Strength Cond Res 37(5): 1145-1156, 2023-The aim of this study was to review articles that performed stretching training and evaluated the effects on muscular strength. Literature search was performed using 3 databases. Studies were included if they compared the effects on strength following stretching training vs. a nontraining control group or stretching training combined with resistance training (RT) vs. an RT-only group, after at least 4 weeks of intervention. The meta-analyses were performed using a random-effect model with Hedges' g effect size (ES). A total of 35 studies ( n = 1,179 subjects) were included in this review. The interventions lasted for a mean period of 8 weeks (range, 4-24 weeks), 3-4 days per week, applying approximately 4 sets of stretching of approximately 1-minute duration. The meta-analysis for the stretching vs. nontraining control group showed a significant small effect on improving dynamic (k = 14; ES = 0.33; p = 0.007) but not isometric strength (k = 8; ES = 0.10; p = 0.377), following static stretching programs (k = 17; ES = 0.28; p = 0.006). When stretching was added to RT interventions, the main analysis indicated no significant effect (k = 17; ES = -0.15; p = 0.136); however, moderator analysis indicated that performing stretching before RT sessions has a small but negative effect (k = 7; ES = -0.43; p = 0.014); the meta-regression revealed a significant negative association with study length (ß = -0.100; p = 0.004). Chronic static stretching programs increase dynamic muscular strength to a small magnitude. Performing stretching before RT and for a prolonged time (>8 weeks) can blunt the strength gains to a small-to-moderate magnitude. Performing stretching in sessions distant from RT sessions might be a strategy to not hinder strength development.

Toward a New Conceptual Approach to "Intensity" in Soccer Player's Monitoring: A Narrative Review.

ABSTRACT: Pillitteri, G, Clemente, FM, Petrucci, M, Rossi, A, Bellafiore, M, Bianco, A, Palma, A, and Battaglia, G. Toward a new conceptual approach to "intensity" in soccer player's monitoring: A narrative review. J Strength Cond Res 37(9): 1896-1911, 2023-In the last decade, monitoring physiological and match-related demands in soccer has become an increasingly common practice in sports sciences. One of the great challenges during monitoring process is the identification of key indicators that permit to generalize evidence and sustain decision-making process during training prescription. Actually, one of the major debates in the scientific community and among practitioners is the identification of the "intensity" concept. Defining a given training session or exercise based on "intensity" is difficult due to the fact that a huge amount of indicators are available (related both to the performed activities and to the athletes' psychophysiological responses). These indicators can lead to specific outcomes with different interpretations. The current narrative review aims to discuss the different measures approaches used in soccer to describe the intensity for both internal and external demands. In addition, a second purpose of this review is to propose general recommendations for combining intensity indicators with the aim of defining an overall intensity score of a training session or drill.

Relationship between external and internal load indicators and injury using machine learning in professional soccer: a systematic review and meta-analysis.

This study verified the relationship between internal load (IL) and external load (EL) and their association on injury risk (IR) prediction considering machine learning (ML) approaches. Studies were included if: (1) participants were male professional soccer players; (2) carried out for at least 2 sessions, exercises, or competitions; (3) correlated training load (TL) with non-contact injuries; (4) applied ML approaches to predict TL and non-contact injuries. TL included: IL indicators (Rating of Perceived Exertion, RPE; Session-RPE, Heart Rate, HR) and EL indicators (Global Positioning System, GPS variables); the relationship between EL and IL through index, ratio, formula; ML indicators included performance measures, predictive performance of ML methods, measure of feature importance, relevant predictors, outcome variable, predictor variable, data pre-processing, features selection, ML methods. Twenty-five studies were included. Eleven addressed the relationship between EL and IL. Five used EL/IL indexes. Five studies predicted IL indicators. Three studies investigated the association between EL and IL with IR. One study predicted IR using ML. Significant positive correlations were found between S-RPE and total distance (TD) (r = 0.73; 95% CI (0.64 to 0.82)) as well as between S-RPE and player load (PL) (r = 0.76; 95% CI (0.68 to 0.84)). Association between IL and EL and their relationship with injuries were found. RPE, S-RPE, and HR were associated with different EL indicators. A positive relationship between EL and IL indicators and IR was also observed. Moreover, new indexes or ratios (integrating EL and IL) to improve knowledge regarding TL and fitness status were also applied. ML can predict IL indicators (HR and RPE), and IR. The present systematic review was registered in PROSPERO (CRD42021245312).

Validity and repeatability of the Pediatric Allergy Questionnaire for Athletes (AQUAped) for the screening of atopy.

BACKGROUND: High atopy prevalence has been reported in athletes. Having an age-specific questionnaire for predicting atopy is important for an optimal management of young athletes. The study objectives were as follows: (i) developing a scoring system for the Pediatric Allergy Questionnaire for Athletes (AQUAped); (ii) identifying the optimal age target within the range 7-14 years; (iii) assessing AQUAped validity and repeatability in the identified target population. METHODS: A total of 133 young athletes (age 7-14 years) were recruited. Following a screening visit, the participants filled AQUAped at baseline (T0) and after 7 days (T1), concomitantly undergoing skin prick testing. Using atopy as the gold standard (positivity to ≥1 aeroallergen), the 12 core items were scored based on their likelihood ratios, and a total score was calculated. The optimal cut-off was identified based on the Youden's criterion. The repeatability of AQUAped was assessed through the intra-cluster correlation coefficient (ICC). The optimal age target was identified as the largest age range associated with an acceptable cross-validated area under the receiver operating characteristic curve (AUC ≥ 0.70) and an excellent ICC (≥0.75). RESULTS: Forty (30%) children were atopic; the optimal age target was 10-14 years (cross-validated AUC = 0.70, ICC = 0.81). AQUAped total score ranged from -26 to 75, and only 5% of non-atopic children had AQUAped ≥ 24. AQUAped ≥ 2 had 82% specificity, 60% sensitivity, and 74% overall accuracy. CONCLUSION: Developing and testing a scoring system for AQUAped showed that it is a valid and reliable tool for the screening of atopy in young athletes aged 10-14 years.

The effect of resistance training programs on lean body mass in postmenopausal and elderly women: a meta-analysis of observational studies.

Aging and menopause are associated with morphological and functional changes which may lead to loss of muscle mass and therefore quality of life. Resistance training (RT) is an effective training mode to increase muscle mass. We reviewed the existing literature to identify studies implementing RT protocols and evaluating muscle hypertrophy exclusively in healthy, postmenopausal and elderly women. Participants' age range was comprised between 50 and 80 years. The primary outcome observed was muscle hypertrophy. Fat mass was also evaluated, if available. PubMed and Web of Science were the screened database, and original articles written in English and published from 2000 up to 2020 were included. 26 articles were considered eligible and included. Quality assessment revealed a "moderate quality" of the included studies, however the majority of studies was able to reach level 4 of evidence and on overall grade of recommendation C. In total, data from 745 female participants subjected to different forms of resistance training were considered. Heterogeneity across studies was present regarding study design, intervention length (mean 16 weeks), training frequency (3 d/w), no. of exercises (n = 7.4) and participants' age (65.8 ± 4.9 years). Small-to-moderate significant increases (k = 43; SMD = 0.44; 95% CI 0.28; 0.60; p < 0.0001) of lean body mass were observed in post-menopausal and elderly women, regardless of age, intervention period, weekly training frequency and no. of exercises. No effects were noted for fat mass (k = 17; SMD = 0.27; 95% CI - 0.02; 0.55; p = 0.07). Studies need to concentrate on providing information regarding training parameters to more effectively counteract the effects of aging and menopause on skeletal muscle mass.

Cardiovascular Responses to Muscle Stretching: A Systematic Review and Meta-analysis.

The aim of this study will be to review the current body of literature to understand the effects of stretching on the responses of the cardiovascular system. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching on responses of the cardiovascular system were investigated. Outcomes regarded heart rate(HR), blood pressure, pulse wave velocity (PWV of which baPWV for brachial-ankle and cfPWV for carotid-femoral waveforms), heart rate variability and endothelial vascular function. Subsequently, the effects of each outcome were quantitatively synthetized using meta-analytic synthesis with random-effect models. A total of 16 studies were considered eligible and included in the quantitative synthesis. Groups were also stratified according to cross-sectional or longitudinal stretching interventions. Quality assessment through the NHLBI tools observed a "fair-to-good" quality of the studies. The meta-analytic synthesis showed a significant effect of d=0.38 concerning HR, d=2.04 regarding baPWV and d=0.46 for cfPWV. Stretching significantly reduces arterial stiffness and HR. The qualitative description of the studies was also supported by the meta-analytic synthesis. No adverse effects were reported, after stretching, in patients affected by cardiovascular disease on blood pressure. There is a lack of studies regarding vascular adaptations to stretching.

Validity and Reliability of an Inertial Sensor Device for Specific Running Patterns in Soccer.

Electronic performance tracking devices are largely employed in team sports to monitor performance and improve training. To date, global positioning system (GPS) based devices are those mainly used in soccer training. The aim of this study was to analyse the validity and reliability of the inertial sensor device (ISD) in monitoring distance and speed in a soccer-specific circuit and how their performance compare to a GPS system. 44 young male soccer players (age: 14.9 ± 1.1, range 9-16, years, height: 1.65 ± 0.10 m, body mass: 56.3 ± 8.9 kg) playing in a non-professional soccer team in Italy, participated in the study. We assessed the players trough a soccer running sport-specific circuit. An ISD and a GPS were used to assess distance and speed. Data was compared to a video reference system, and the difference were quantified by means of the root mean square error (RMSE). Significant differences were found for both GPS and ISD devices for distance and speed. However, lower error for distance (dRMSE 2.23 ± 1.01 m and 5.75 ± 1.50 m, respectively) and speed (sRMSE 0.588 ± 0.152 m·s-1 and 1.30 ± 0.422 m·s-1, respectively) were attained by the ISD compared to the GPS. Overall, our results revealed a statistically significant difference between systems in data monitoring for either distance and speed. However, results of this study showed that a smaller error was obtained with the ISD than the GPS device. Despite caution is warranted within the interpretation of these results, we observed a better practical applicability of the ISD due to its small size, lower cost and the possibility to use the device indoor.

Peripheral Nerve Responses to Muscle Stretching: A Systematic Review.

Stretching is commonly used to increase range of motion and flexibility. Therefore, investigations are usually oriented towards the muscle-tendon unit. Limited evidence exists regarding potential effects of stretching on peripheral nerves which lie within muscles. The objective of this investigation will be to elucidate the responses of peripheral nerves to stretching. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching protocols on responses of peripheral nerves were retrieved for investigation. The NHLBI tool was used for quality assessment. Outcomes included nerve stiffness, nerve displacement, pain pressure thresholds and resistive torque. A total of 10 studies were considered eligible and were included in this investigation. The quality assessment of the studies revealed an overall "fair to good" methodological quality across the included studies. All studies except for one involved healthy participants. High heterogeneity of stretching protocols was retrieved. As a consequence of stretching, nerve stiffness (-15.6%) and pain pressure thresholds (-1.9kg) increased. Nerve displacements on each movement plane for all the considered nerves and nerve deformation were also frequently observed. Peripheral nerve responses to muscle stretching include decreased nerve stiffness and increased pain pressure thresholds. Nerve displacement also frequently occurs. It is still unclear if reduced nerve displacement may lead to clinical outcomes. There is a lack of longitudinal studies regarding peripheral nerve adaptations to stretching.

Food literacy predictors and associations with physical and emergent literacy in pre-schoolers: results from the Training-to-Health Project.

OBJECTIVE: Food literacy (FL) is a crucial need encompassing basic literacy and fundamental movement skills. The present study aimed to investigate the FL level in pre-schoolers and to evaluate the effect of potential predictors and the associations with gross motor and emergent literacy skills. DESIGN: Cross-sectional study conducted within the Training-to-Health Project. SETTING: Kindergartens (n 21) in the Palermo City Council, Italy. PARTICIPANTS: Pre-school children aged 3-6 years (n 921) followed education sessions on nutritional topics, practical activities and compiled prearranged sheets. FL was assessed by the five-domain toolkit 'preschool-FLAT'; gross motor and emergent literacy skills were assessed by the Italian version of the gross motor development test and the PRCR-2/2009, respectively. Correlation and regression analyses were performed to assess relationships between FL scores and gender, age, weight, height, BMI, gross motor and emergent literacy skills. RESULTS: Independent predictors (ß, se) of higher FL were female gender (1·06, 0·315, P < 0·01), older age (0·08, 0·019, P < 0·001) and greater height (0·13, 0·03, P < 0·001). The adjusted coefficients were significant for quotient of gross motor development and in particular for the locomotor component (0·03, 0·01, P < 0·01 and 0·16, 0·046, P < 0·001, respectively). Almost all associations with the emergent literacy skills were significant (ß = -0·02 to 0·47). CONCLUSIONS: The study suggests that children raised in an environment where both cognitive and motor skills are enhanced can have better chances of increasing FL and success at school. Thus, the need for monitoring FL and its predictors since early age is highlighted.

Race Profiles of Rowers During the 2014 Youth Olympic Games.

Cerasola, D, Cataldo, A, Bellafiore, M, Traina, M, Palma, A, Bianco, A, and Capranica, L. Race profiles of rowers during the 2014 Youth Olympic Games. J Strength Cond Res 32(7): 2055-2060, 2018-Among the different factors affecting the outcome of elite rowing competitions, pacing strategy plays a relevant role. The purpose of this study was to analyze the race profiles of youth athletes competing at the 2014 Youth Olympic Games over a distance of 1,000 m. According to the competition outcome of sculling and sweep events, 96 youth (17-18 years) rowers (48 male and 48 female) were divided into winner (W), not winner (NW), qualified (Q), and not-qualified (NQ) athletes. The time during the 1,000-m race distance was considered at 0-500 m (T1) and 500-1000 m (T2). The average speed of T1 and T2 were normalized in relation to the average speed of the whole race. In both sexes, W rowers showed higher (p > 0.05) T2 values (100.8 ± 0.9%) with respect to T1 (99.2 ± 0.9%) ones. Female athletes showed a higher (p ≤ 0.05) T1 with respect to T2 in NW, Q, and NQ, whereas male athletes exhibited a higher T1 (p ≤ 0.05) than T2 speed only in NQ. While to be admitted to the final phase of the competition, the rowers tended to favor a positive race strategy (88%); during the final phase, a difference (p = 0.43) emerged for outcome, with the majority of medalists (67%) adopting a negative race strategy. These results suggest that winners have applied a different race strategy compared with the other groups in consequence to a higher efficiency of anaerobic metabolism.

Vibration effect on ball score test in international vs. national level table tennis.

In table tennis, motor skills are crucial for discriminating player level. However, there is a dearth of studies exploring the impact of a vibrational stimulus on performance. Thirty-four male players (age 25±2 years; body mass index, BMI 23.4±1.2 kg·m -2 ) participated in the study. Seventeen played at international level (IL), while the remaining 17 played at national level (NL). The participants underwent a ball-handling test, the ball score, before (PRE) and after (POST) a vibrational stimulus. Intra-class correlation (ICC) for the ball score result showed good reliability (ICC 0.87 for IL and 0.80 for NL). Repeated measures ANOVA showed differences between groups for ball score (p=0.000) and a significant group×time interaction (p=0.004). Better performances were observed for the IL group than for the NL group, significantly only for POST. Vibration produced positive and negative effects in IL and NL groups, respectively.

The influence of the stomatognathic system on explosive strength: a pilot study.

[Purpose] Recent findings suggest there is an interesting interaction between the stomatognathic system and the musculoskeletal system. The aim of this study was therefore to examine the influence of the temporomandibular joint on the explosive strength of the lower limbs. [Subjects and Methods] An observational study was carried out. The subjects were 60 male football players who voluntarily participated in the investigation. After a warm-up phase of 10 minutes, each participant performed three Squat Jumps (SJ) with different mandible positions: mouth closed and mouth open. SJ heights were recorded using a Sensor Medica force platform and the FreeMed system. [Results] Sixty participants were enrolled in this study (age: 24 ± 7 yrs; height: 174 ± 4.6 cm; weight 63.7 ± 7.6 kg). The SJ heights with the mouth closed, 38.50 ± 4.0 cm, were shorter than those with the mouth open, 40.4 ± 4.1 cm. Statistical analysis showed there was a statistically significant difference between the performances. [Conclusion] This pilot study highlighted that occlusal factors can influence physical performance and this could have practical applications in sports and exercise science. However, our results have to be confirmed in studies with larger numbers of participants and supported by other investigations.

Group fitness activities for the elderly: an innovative approach to reduce falls and injuries.

AIM: The aim of this study was to examine the opportunity to adopt, for the elderly, already validated function ability tests to better understand how to prevent falls and injuries and to better plan group fitness activities like ballroom dance classes (e.g., Valzer, Polka, Mazurka). METHODS: A cross-sectional study was conducted. The Berg Balance Scale (BBS) and the Barthel Index (BI) were administered and the occurrence of falls during the previous 2 years was evaluated by anamnesis. One hundred and twenty-two elderly subjects living in Palermo city participated to the study. According to the anamnesis, subjects were divided into two groups: experimental group (EG) and control group (CG). The EG consisted of 75 subjects attending classes of ballroom dancing (73.0 ± 5.6 years 26.1 ± 3.9 BMI), while the CG included 47 volunteers (74.3 ± 5.4 years, 26.8 ± 4.4 BMI). A threshold of 70 % for both scales (BBS-70 and BI-70 %) was set, according to the aims of the study. STATISTICA software was adopted to perform an unpaired t test. A P value lower than 0.05 was considered to be statistically relevant. RESULTS: The BI and BBS of CG were 76.7 ± 33.08 and 30.9 ± 14.9, respectively, while the BI and BBS of EG were 98.1 ± 6.9 and 50.5 ± 54. In EG the BBS-70 % showed 96.0 % of cases compared to 27.6 % of the CG. The BI showed a similar trend to BBS. In EG the BI-70 % showed 98.6 % of cases, while the BI-70 % of CG showed 70.2 % of cases. Moreover, only 36.0 % of EG reported falls previously, while CG reported 53.2 % of falls during the same period of time. CONCLUSION: The BBS seems to be a valid and reliable tool able to be adopted also by professionals of the ballroom dancing sector (e.g., Valzer, Polka and Mazurka classes). Instructors may evaluate the functional ability of their attendees through BBS to easily obtain more information and better plan ballroom dance classes. Moreover, we highlight that these conclusions need to be supported by other studies with different cohorts and a larger population scale.

Acute effects of different administration order of stretching exercises: effects on range of motion and cross-over effect.

BACKGROUND: The aim of this manuscript is to investigate if stretching exercise administration order may influence outcomes pertinent to range of movement (ROM). METHODS: A total sample of 108 participants was randomized into five groups. Eight sets of unilateral static stretching (SS) of 30s duration each with a 30s rest were administered to the right leg. One group underwent SS of the knee extensors (KE), another to the knee flexors (KF), another first to the KE and then to the KF, another first to the KF and then to the KE while the last group was used as control (CG). Each group was assessed for ROM of both lower limbs for either the KE and KF motion (passive hip extention [PHE] and passive straight leg raise [PSLR], respectively). Measures were assessed before (T0), immediately after (T1), and 15 minutes after the intervention (T2). RESULTS: No differences were observed for time (T0 vs. T1 vs. T2) for all measures in the CG for both limbs. Time-x-group interactions were observed only in the intervention limb (P<0.0007 and 0.004, ES 0.73 and 0.55, for KE and KF, respectively). Within the intervention limb, a significant increase in the PHE was observed from T0 to T1 only in the KE and KF/KE groups. For measures of the PSLR, a significant increase was observed from T0 to T1 only in the KF and KE/KF groups. No differences neither for time or group were observed in the control limb. CONCLUSIONS: Our results highlight that exercise administration order has an effect on ROM outcomes. Measures of ROM significantly increase only for the last stretched muscle in each intervention group. No crossover effect was observed in the contralateral limb.

Sex differences in the determination of prescribed load in ballistic bench press.

Introduction: The objectives of the present study were twofold: first, to identify the specific relative load at which the concentric motion transforms into a purely propulsive action among women, and second, to compare the load-velocity relationships between men and women during the bench press throw. Methods: Fourteen men and fourteen women participated in a test where they progressively increased the load until reaching their one-repetition maximum (1RM) in the bench press exercise. Linear regression models were employed to elucidate the relationships between load and velocity, as well as load and the propulsive phase (% of total concentric time). Additionally, ANCOVA was utilized to compare the linear regression models between men and women. Results: The results revealed strong and linear associations between load and mean propulsive velocity (MPV) for both men and women, as well as between load and the propulsive phase. Notably, there were significant differences in MPV and the propulsive phase concerning load between men and women. Women transitioned into a fully propulsive concentric phase at approximately 80% of their 1RM, while men achieved this entirely propulsive phase at around 85% of their 1RM. Furthermore, women exhibited reduced velocities when handling lighter relative loads compared to men. Conversely, women demonstrated higher velocities when dealing with loads exceeding 85% of their 1RM in contrast to their male counterparts. Discussion: These findings hold notable implications for prescribing bench press throw loads for women, which should differ from those recommended for men. Further studies are necessary to validate the efficacy of the proposed load recommendations.

Relationship between Lifestyle Determinants and Perceived Mental and Physical Health in Italian Nursery and Primary School Teachers after the COVID-19 Lockdown.

The COVID-19 lockdown and the consequent distance school learning made epochal changes in children's lifestyles; however, little is known about the lockdown effects on school teacher habits. The aim of this observational study is to examine differences in the lifestyle of nursery (NS) and primary (PS) school teachers after one of the COVID-19 lockdowns and investigate the relationship between perceived physical/mental health and demographics, weight status and lifestyle determinants, such as adherence to the Mediterranean Diet (MD) and physical activity level (PAL). A total sample of 265 participants (49.22 ± 6.95 years) filled out an online information questionnaire and standardized questionnaires to collect data on the Physical Component Summary (PCS), Mental Component Summary (MCS), PAL and MD-adherence. A t-test or ANOVA analysis was used to assess differences between quantitative variables: Mann-Whitney U or Kruskal-Wallis tests for qualitative variables. Spearman's correlations and multinomial logistic regression analyses were performed to identify categorical factors associated with classes of PCS and MCS. Teachers showed sufficient/high PAL, with a significantly higher level in the PS group (p < 0.05). This last showed a higher PCS score (p < 0.05). No differences between groups were found for MD-adherence, which was moderate/fair in both groups, and MCS, which was sufficient/good. Logistic regression showed that the only positive predictor of a high PCS was being physically active (OR 2.10, 95%CI 1.05-4.2, p < 0.05), while MCS was positively associated with normal weight status (OR 0.48, 95%CI 0.33-0.78, p = 0.020). This study highlights that PS teachers are more active than the NS group and perceive a higher physical health level. Mere predictors of physical and mental well-being are PA practice and being normal weight, respectively. This suggests that interventions to improve perceived health in this work category should be focused on the promotion of physical activity practice and on the maintenance of an optimal weight status.

The involvement of MMP-2 and MMP-9 in heart exercise-related angiogenesis.

BACKGROUND: Little is known about the involvement of matrix metalloproteinases (MMPs) in cardiac vascular remodelling induced by exercise. Our aim was to evaluate and localize MMP-2 and MMP-9's activities in relation to capillary proliferation in mouse hearts trained for 15, 30 and 45 days. METHODS: Sixty-three mice were randomly assigned to 7 groups: four control sedentary groups (C0, C15, C30 and C45) and three groups trained by an endurance protocol (T15, T30 and T45). MMP-2 and MMP-9 were examined with zymography and immunostaining analyses. Capillary proliferation was evaluated counting the number of CD31-positive cells. RESULTS: Different activity patterns of the latent form of both MMPs were found. Pro-MMP-9 increased after 15 days of training; whereas pro-MMP-2 gradually decreased after 30 and 45 days of training below the control groups. The latter was inversely correlated with capillary growth. MMP-9 was mainly localized in myocardiocytes and less evident in capillaries. Conversely, MMP-2 was more intense in capillary endothelial cells and slightly in myocardiocytes. CONCLUSIONS: A different spatiotemporal modulation of pro-MMP-2 and pro-MMP-9 activities has been detected in the myocardium during angiogenesis related to the aerobic training. These results can be useful to draw up training protocols for improving the performance of healthy and diseased human hearts.

Lower limb muscle activation pattern in male soccer players with lumbar hyperlordosis.

OBJECTIVE: the aim of the current study was to compare the lower limb muscle activation pattern in soccer players with and without lumbar hyperlordosis during single-leg squat performance. METHODS: thirty male collegiate soccer players (15 with and 15 without lumbar hyperlordosis) performed the SLS task. Surface EMG was used to record the activation of eleven lower limb muscles. The activation of these muscles reduces to 100 points during the SLS cycle, where 50% demonstrates the maximum knee flexion, and 0% and 99% demonstrate the maximum knee extension. RESULTS: soccer players with lumbar hyperlordosis had higher muscle activation than those with normal lumbar lordosis in gluteus maximus, biceps femoris, and medial gastrocnemius. By contrast, they had lower gluteus medius, vastus medialis oblique, rectus femoris, soleus, and medial gastrocnemius (only in the final ascent phase of the SLS) muscle activity than the normal group during the SLS. CONCLUSION: this alteration may negatively affect targeted muscle performance during the SLS. Subsequent study is required to specify whether such an alteration in the lower limb muscle could be accompanied by injury in soccer players and change in their athletic performance.