Recreational football practice attenuates postprandial lipaemia in normal and overweight individuals.

INTRODUCTION: The aim of the present study was to examine the effects of playing football on postprandial lipaemia in normal and overweight individuals. METHODS: Fifteen (7 normal weight, age = 32.3 ± 6.0 years, BMI = 22.8 ± 3.4 kg/m2 and 8 overweight, age = 33.3 ± 5.5 years, BMI = 29.2 ± 3.2 kg/m2, mean ± SD) recreational football players were recruited. On the evening of day 1, participants played a 60-min 9-a-side football match (FOOT) or rested (control; CON) in a randomised counterbalanced cross-over design. Activity profile, heart rate and rate of perceived exertion were recorded. The next morning (> 10 h after the match), blood samples were collected before (0), 0.75, 2, 4, and 6 h after a high-fat meal. RESULTS: Total area under the curve for triglycerides were 22% and 28% lower for the normal weight (p < 0.01; 95% CI - 2.45 to - 0.68; ES = 0.87) and overweight (p < 0.01; 95% CI - 8.14 to - 0.88; ES = 0.68) groups in the FOOT compared to the CON. The postprandial incremental area under the curve for triglycerides was 31% lower in the normal weight group (ES = 0.79) for the FOOT compared to CON trial and a discernible trend was shown for the overweight group (22%; ES = 0.51). Two-hour Insulin Sensitivity Index was lower (ES = - 0.95) for FOOT compared to CON trial in the overweight group only. CONCLUSION: Playing a 60-min football match can attenuate the triglyceride response to a high-fat meal in normal and overweight individuals.

Testing strength and power in soccer players: the application of conventional and traditional methods of assessment.

Soccer is a highly complex sport influenced by many physical, psychological, tactical, and technical factors. In terms of basic physical components, strength and power are considered requisites for many important actions such as tackling, jumping, and shooting. Hence, assessment of strength and power is commonly performed within a soccer club's test battery. The objective is to use valid, reliable, and sensitive measures that allow for trustworthy analysis of the physical characteristics of players. Before any credence can be placed in test results, test's validity, reliability, and sensitivity needs to be established. This will allow practitioners to make informed decisions about test selection. This review examines the reliability, validity, and sensitivity of different strength and power assessments in soccer. The suitability of conventional and functional tests is detailed and the strengths and weaknesses of isokinetic dynamometry, hand-held dynamometry (HHD), repetition maximum, and power testing are also addressed. Generally, the tests considered in this review provide moderate to high reliability in soccer players of different training level. Similarly, the consensus demonstrates test methods to be sensitive to training interventions. In comparison, test validity seems less established. Isokinetic dynamometry has often been recognized as a gold standard measure of testing strength. Other methods of assessment are emerging as viable options (e.g., HHD), likely due to functionality and suitability of testing. Given the demands within a soccer club setting, practitioners should endeavor to use testing procedures that are informative yet not time consuming or labor intensive. By providing this, practitioners may have the option to perform more regular monitoring throughout the season rather than a limited number of specific time periods.

Acute responses of soccer match play on hip strength and flexibility measures: potential measure of injury risk.

Regular measurements of groin risk factors may offer a preventive measure against injury. Therefore, the aim of this study was to (1) determine minimal detectable change (MDC) and reliability of hip flexibility and strength measures and to (2) identify the effect soccer match play load has on these measures. Reliability was determined for bent knee fall out test, hip abduction and adduction (hand-held dynamometry (HHD)) in 20 trained youth male soccer players. Reliability was evaluated with the intra-class correlation coefficient (ICC[2,1]), 95% confidence intervals (CI). Hip strength and flexibility measures were taken before and after an international friendly match. Intra-rater reliability ICC ranges were bent knee fall out (0.75-0.90), abduction (0.83-0.90) and adduction (0.72-0.96). Inter-rater ICCs (95% CI) were bent knee fall out test [0.75 (0.39-0.90) right, 0.71 (0.27-0.89) left hip]; abduction [0.80 (0.50-0.92) right, 0.81 (0.53-0.92) left hip] and adduction [0.72 (0.31-0.89) right, 0.70 (0.26-0.88) left hip]. MDCs were as low as 20.7% of the mean for hip flexibility and 12.5% for strength. In conclusion, HHD and the bent knee fall out test are reliable tools to measure changes in hip strength and flexibility. Finally, a threshold may exist in which match play load negatively impacts hip flexibility.

Effect of an injury prevention program on muscle injuries in elite professional soccer.

Due to the continual physical, physiological, and psychological demands of elite level soccer increasing the incidence and risk of injuries, preventative training programs have become a common feature of soccer players training schedule. The aim of the current investigation was to examine the effectiveness of a structured injury prevention program on the number of muscle injuries and the total number of injuries within elite professional soccer. The present study was conducted over 2 consecutive seasons, of which the first (2008-2009) being the intervention season and the second the control season (2009-2010). In total, 26 and 23 elite male professional soccer players competing within the Scottish Premier League and European competition participated. The training program was performed twice weekly for the entirety of the season (58 prevention sessions). The results revealed an increase in the total number of injuries within the intervention season (88 vs. 72); however, this was largely due to the greater number of contusion injuries sustained within the intervention season (n = 44) when compared with control season (n = 23). Significantly less muscle injuries were observed during the intervention season (moderate effect), and this occurred concomitant with a bigger squad size (large effect, p < 0.001). The findings from this study identify that a multicomponent injury prevention-training program may be appropriate for reducing the number of muscle injuries during a season but may not be adequate to reduce all other injuries.

The Use of Recovery Strategies in Professional Soccer: A Worldwide Survey.

PURPOSE: To survey soccer practitioners' recovery strategy: (1) use, (2) perceived effectiveness, and (3) factors influencing their implementation in professional soccer. METHODS: A cross-sectional convenience sample of professional soccer club/confederation practitioners completed a web-based survey (April to July 2020). Pearson chi-square and Fisher exact tests with Cramer V (φ - c) assessed relationships and their strength, respectively, between the perceived effectiveness and frequency of strategy use. RESULTS: A total of 80 soccer practitioners (13 countries) completed the survey. The 3 most important recovery objectives were "alleviating muscle damage/fatigue," "minimizing injury risk," and "performance optimization." The most frequently used strategies were active recovery, structured recovery day, extra rest day, massage, cold-water therapy, and carbohydrate provision (predominantly on match day and match day + 1). Relationships were identified between perceived effectiveness and frequency of strategy use for sleep medication (P < .001, φ - c = 0.48), carbohydrate provision (P = .007, φ - c = 0.60), protein provision (P = .007, φ - c = 0.63), an extra rest day (P < .001, φ - c = 0.56), and a structured recovery day (P = .049, φ - c = 0.50). CONCLUSIONS: The study demonstrates that professional soccer practitioners have a range of objectives geared toward enhancing player recovery. A disconnect is apparent between the perceived effectiveness of many recovery strategies and their frequency of use in an applied setting. Novel data indicate that strategies are most frequently employed around match day. Challenges to strategy adoption are mainly competing disciplinary interests and resource limitations. Researchers and practitioners should liaise to ensure that the complexities involved with operating in an applied environment are elucidated and apposite study designs are adopted, in turn, facilitating the use of practically effective and compatible recovery modalities.

The Effects of a Single Versus Three Consecutive Sessions of Football Training on Postprandial Lipemia: a Randomized, Controlled Trial in Healthy, Recreationally Active Males.

BACKGROUND: Exercise frequency is important for maintaining health; however, its effects on postprandial responses remain largely unknown. Better understanding this during popular sports activities such as football may influence exercise habits. Therefore, the aim of the present study was to examine the effects of playing one single versus three consecutive days of 60-min small-sided football matches on postprandial lipemia. METHODS: Fifteen males performed either one (1FOOT; n = 7) or three 60-min football (3FOOT; n = 8) sessions across an 8-day trial period. On day 1, a blood sample was collected at fasted (0 min) and 0.75, 2, 4, 6 h after a high-fat meal. Participants were then randomly allocated to the 1FOOT (day 7) or 3FOOT (days 5, 6, 7) condition. On day 8, they repeated the high-fat meal and blood sampling for 6 h following the meal. Postprandial total and incremental area under the curve (AUC, iAUC, respectively) were calculated. RESULTS: The postprandial triglyceride iAUC was 41% lower from pre- to post-measures for the 1FOOT (p < 0.05; ES = 1.02) and 15.7% lower for the 3FOOT (ns; ES = 0.41). Total triglyceride AUC was lower (26%) post-football matches in the 3FOOT group only (p < 0.01; ES = 1.23). In 3FOOT, insulin concentration was lower for post- compared to pre-measures at 0.75 and 2 h, respectively (p < 0.001). CONCLUSION: One single 60-min small-sided football match lowered postprandial TG incremental area under the curve while performing three consecutive days of football matches did not result in a greater attenuation. TRIAL REGISTRATION: ISRCTN17934193 , registered 06 April 2019.

Match-Related Time Course of Perceived Recovery in Youth Football Players.

PURPOSE: To examine the reproducibility of the Perceived Recovery Status (PRS) scale in football players and describe the time course of the PRS in response to a football match. METHODS: Twenty trained youth players (mean [SD] age = 16.2 [1.2] y, height = 1.75 [0.07] m, body mass = 64.0 [7.8] kg) took part in the study. PRS was collected -2 h and -30 min before and +15 min, +3 h, and +24 h after an international football match. Players were categorized into 2 groups based on their playing time (≤45 and 90 min). RESULTS: Reproducibility of the PRS was high (intraclass correlation coefficient = .83, typical error = 0.59, coefficient of variation = 9.9%) between the 2 prematch measures. Overall, PRS was lower at +15 min (4.0 [1.5]; P < .01, effect size = 2.2) and +3 h (4.7 [1.6]; P < .01, effect size = 1.5) compared with -30 min (7.1 [1.3]); +15 min was lower than +24 h (6.1 [1.3]; P < .01, effect size = 1.5). No differences between groups for PRS scores at any of the time points were found. CONCLUSIONS: The PRS is a reproducible tool for monitoring perceptions of recovery to football activity and is sensitive to time-course changes relating to a match. The scale is an easy and efficient tool that can be used to monitor an aspect of recovery.

The effect of a concentrated period of soccer-specific fitness training with small-sided games on physical fitness in youth players.

BACKGROUND: It is unknown whether a concentrated period of small-sided games and high intensity training is an effective training approach in youth soccer players. The aim of the study was to examine the effect of a concentrated period of soccer specific training on physical fitness in youth players. METHODS: Nineteen male soccer players, from two teams, participated (mean age: 16.2±0.8 years; body mass: 58.2±7.6 kg; height: 170.8±7.7 cm). One team performed 5 days of small-sided games and high intensity training (SSG & HIT; N.=12) and the other team regular soccer training with 1 day of SSG and HIT (REG; N.=7) weekly for 4 weeks. The 30-15 intermittent fitness test (30-15 IFT), countermovement jump (CMJ) and change of direction (COD) performance were measured pre and post intervention. Heart rate (HR) and rating of perceived exertion (RPE) were recorded and session load calculated (RPE x minutes). RESULTS: Average percentage of maximum HR and session load were 83% and 344 AU for the SSG & HIT versus 73% and 253 AU for the REG (P<0.05). 30-15 IFT improved for the SSG & HIT (from 17.0±1.1 to 18.4±0.8 km/h; P<0.05; ES=0.57) with no difference for the REG group (Pre: 17.9±1.3, Post: 18.2±1.6 km/h, ES=0.10). CMJ and COD were unchanged in both groups and no injuries were reported. CONCLUSIONS: A 4-week concentrated period of daily SSG & HIT is effective for improving endurance performance in youth soccer players. This was without injuries and without negating performance in power and change of direction.

Postprandial lipaemia 10 and 34 hours after playing football: Does playing frequency affect the response?

Elevated postprandial triglyceride (TG) is associated with increased risk of cardiovascular disease. The time window for the last bout beneficial effect on postprandial lipaemia after football play is unknown. The aim of the present study was to examine whether playing affects postprandial TG during 1.5 day of reduced activity. Eighteen males were randomly allocated to perform either 1 (1FOOT; n = 9; age = 33.0 ± 5.0 yrs; body mass index = 24.2 ± 3.6 kg/m2) or 3 (3FOOT) consecutive days of 60-min 5 vs 5 football (n = 9; age = 32.8 ± 5.2 yrs; body mass index = 26.2 ± 4.1 kg/m2) matches across a 5-day study period. They arrived to the laboratory 10 hrs and 34 hrs after the final football session and blood samples were collected at fasted (0 min) and 45, 90, 240 and 360 min post a high fat load meal. There were non significant increase for postprandial TG AUC (9.1%; p = 0.17; 95%CI = -0.43 to 2.0; ES = -0.23) and iAUC (14.2%; p = 0.43; 95%CI = -0.92 to 1.9; ES = -0.24) between 10 and 34 hrs after the 1FOOT. For the 3FOOT, there was a non significant decrease in postprandial TG AUC (-2.7%; p = 0.73; 95%CI = -2.0 to 1.5; ES = 0.05) and iAUC (-17.5%; p = 0.41; 95%ci = -2.5 to 1.1; ES = 0.31) from 10 to 34 hrs, respectively. Performing three consecutive days of football exercise may offer no greater protective effect for postprandial TG before a period of reduced activity, compared to a single session.

Does Early Recruitment Predict Greater Physical Performance in Academy Soccer Players?

The purpose of this longitudinal study was to investigate whether recruitment status influences neuromuscular and endurance performances in academy soccer players over a 2-year training period (from Under-16 to Under-18). Thirty-seven male soccer players from an elite academy were selected and divided in two cohorts according to their recruitment status: Early Recruitment group (ER; n = 16), training and competing for the academy since Under-14 and Under-15 age groups, and; Late Recruitment group (LR; n = 21) included in the academy training process at Under-16. Squat (SJ) and countermovement jump with (CMJwA) and without arms swing (CMJ), 10-m sprint time, and Vam-Eval test (MAV) were performed in three successive occasions always pre-season (Under-16, Under-17 and Under-18 age groups, T1, T2, and T3 respectively). A two-way (recruitment status × time) analysis of variance with repeated measurements was performed as well as the magnitude of difference using both effect size and magnitude-based inferences. There was no difference between ER and LR for MAV, 10 m-sprint, and SJ from T1 to T3. However, LR players presented non-significant small and possibly greater improvement in CMJ (ES = 0.4) and CMJwA (ES = 0.4) than ER players at T2. These data indicate that early recruitment is not likely to result in greater physical performance improvement at the age of 18.

Evidence of sub-optimal sleep in adolescent Middle Eastern academy soccer players which is exacerbated by sleep intermission proximal to dawn.

The purpose was to assess sleep patterns, quantity and quality in adolescent (16.2 ± 1.2 yr) Middle Eastern academy soccer players (n = 20) and the influence of an intermission upon these characteristics. On a 17-day training camp (located one time zone west of home) including three discrete matches, sleep was assessed pre- (PRE) and post-match (POST) via wrist actigraphy. Retrospective actigraphy analysis identified sleep characteristics, including if players experienced a sleep intermission (YES) or not (NO) proximal to dawn, and bedtime (hh:mm), get-up time (hh:mm), time in bed (h), sleep duration (h) and sleep efficiency (%). Within YES two bouts were identified (BOUT1 and BOUT2). No differences were seen between PRE and POST, nor between BOUT1 and BOUT2 (p > .05). Overall players did not meet National Sleep Foundation (NSF) guidelines (7:04 ± 1:16 h vs. recommended 8-10 h for 14-17 yr). Sleep duration was significantly reduced (∼ -13% or -1:06) in YES compared to NO (6:33 ± 1:05 vs. 7:29 ± 1:17, p < .01). Despite players in YES waking earlier due to an intermission, they did not compensate for this with a later wake time, rising significantly earlier compared to NO (09:40 ± 00:38 vs. 10:13 ± 00:40, p < .05). These players on average do not obtain sufficient sleep durations relative to NSF guidelines, with decrements increased by an intermission proximal to dawn. High inter- and intra-individual variance in the players sleep characteristics indicates the need for individualized sleep education strategies and interventions to promote appropriate sleep.

Agility in Team Sports: Testing, Training and Factors Affecting Performance.

BACKGROUND: Agility is an important characteristic of team sports athletes. There is a growing interest in the factors that influence agility performance as well as appropriate testing protocols and training strategies to assess and improve this quality. OBJECTIVE: The objective of this systematic review was to (1) evaluate the reliability and validity of agility tests in team sports, (2) detail factors that may influence agility performance, and (3) identify the effects of different interventions on agility performance. METHODS: The review was undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We conducted a search of PubMed, Google Scholar, Science Direct, and SPORTDiscus databases. We assessed the methodological quality of intervention studies using a customized checklist of assessment criteria. RESULTS: Intraclass correlation coefficient values were 0.80-0.91, 0.10-0.81, and 0.81-0.99 for test time using light, video, and human stimuli. A low-level reliability was reported for youth athletes using the video stimulus (0.10-0.30). Higher-level participants were shown to be, on average, 7.5% faster than their lower level counterparts. Reaction time and accuracy, foot placement, and in-line lunge movement have been shown to be related to agility performance. The contribution of strength remains unclear. Efficacy of interventions on agility performance ranged from 1% (vibration training) to 7.5% (small-sided games training). CONCLUSIONS: Agility tests generally offer good reliability, although this may be compromised in younger participants responding to various scenarios. A human and/or video stimulus seems the most appropriate method to discriminate between standard of playing ability. Decision-making and perceptual factors are often propositioned as discriminant factors; however, the underlying mechanisms are relatively unknown. Research has focused predominantly on the physical element of agility. Small-sided games and video training may offer effective methods of improving agility, although practical issues may hinder the latter.

Factors affecting match running performance of elite soccer players: shedding some light on the complexity.

Time-motion analysis is a valuable data-collection technique used to quantify the match running performance of elite soccer players. However, interpreting the reductions in running performance in the second half or temporarily after the most intense period of games is highly complex, as it could be attributed to physical or mental fatigue, pacing strategies, contextual factors or a combination of mutually inclusive factors. Given that research in this domain typically uses a reductionist approach whereby match-running performance is examined in isolation without integrating other factors this ultimately leads to a 1-dimensional insight into match performance. Subsequently, a cohesive review of influencing factors does not yet exist. The aim of this commentary is to provide a detailed insight into the complexity of match running performance and the most influential factors.